Mittwoch, 21. April 2021

Feser criticism in a nutshell (short version)

I criticize here, with the help of many critical quotations from intelligent thinkers, two important theses of Catholic Thomistic philosophy, the proof of God from motion and natural law morality, on the basis of the book "The Last Superstition" by the Thomism popularizer Edward Feser.

The point I'm trying to make is not the following:

"Aquinas' "First Way", IMO, is just vacuous scholastic twaddle without justifying this anachronistic Aristotlean assumption." (opinion from the internet)

There may be a grain of truth in this opinion if one also considers the following quote:

"What at first seemed to be a simple proof is in fact a world view in miniature, an image of the world projected onto half a page. Is it a proof of God's existence which, taken by itself, compels assent, quite independent of what we may think of Thomas' metaphysics or the remainder of his System? Definitely not." (Walter Kaufmann - Critique of Religion and Philosophy)

However, my criticism of the proof of God consists, at least in part, in allowing certain Aristotelian views to hold and yet declaring the proof invalid.

So here is a summary of the alleged proof:

"In Chapter 3 Feser discusses three of St. Thomas's magnificent five ways, describing the first way with customary clarity and succinctness. Noting that "no potential can make itself actual" (p. 91), Feser points to St. Thomas's well known example of a man pushing a stone with a stick. The stone's potency to move is actualized by the stick, whose potency to move is actualized by the hand, whose potency to move is in turn actualized by the firing of certain motor neurons, and so forth. In this, an essentially subordinated series, each actualized potency is simultaneously actualized by a superior. Feser notes that such a series "of its nature, must have a first member" because "it is only the first member which is in the strictest sense really doing or actualizing anything" (p. 95). Without a first Pure Act free from all admixture of potency, there are no other actualities, nor can there be, since all others "exist at all only insofar as yet earlier ones do" (p. 95)." (an official review of Edward Feser's Last Superstition by Michael O'Halloran)

By "and so forth" Feser means the existence of molecules, atoms and quarks and whatever else may be smaller. Aquinas would add:

"[T]his cannot go on to infinity, because then there would be no first mover, and, consequently, no other mover, seeing that subsequent movers move only inasmuch as they are moved by the first mover." (Aquinas)

And he concludes:

"Therefore it is necessary to arrive at a first mover, moved by no other; and this everyone understands to be God." (Aquinas)

However, one does not arrive at an in every respect actual unmoved mover:

"Assuming that Aquinas can block a regress in the case of movers and things moved, why must the primary mover be not just unmoved, but unmovable? Aquinas thinks that if the mover of some moved thing is not itself moved, it is an unmovable mover [...]. What justification does he have for supposing that an unmoved mover is unmovable? The sort of causal series he has in mind in the proof from motion has as a member something, M, that is being moved. M’s going from being in potentiality with respect to some state S to being in actuality with respect to S needs to be explained by some primary mover, P. All that is required of P is that it be in actuality with respect to S; P’s being in actuality with respect to S is what makes P the primary mover in this causal series ordered per se. So in order to count as a primary mover, as the stopping point in a causal series ordered per se, P must be unmoved (because it is in actuality) in the relevant respect. But it does not follow from this that P must be unmoved (and hence in actuality) in all respects. If P were in actuality in all respects, P would be absolutely unmoved and unmovable, but the fact that P is unmoved with respect to some state S does not entail that P is unmovable. Given that Aquinas’s argument so far has shown only that there must be some primary mover that is in actuality in the respect relevant to the particular case of motion at hand, it seems likely that there will be very many relatively uninteresting primary movers. The fire in our paradigm case seems to be a suitable primary mover, animals (or their souls) might be unmoved movers, and some of Aquinas’s own examples of causal series ordered per se apparently have human beings filling the role of primary mover, at least as Aquinas describes them. We might call fire, animals, human beings, and other natural unmoved movers (if there are any) mundane primary movers. The problem, then, is that the proof from motion gives us no reason to suppose there are any primary movers other than mundane primary movers." (Scott Macdonald - Aquinas’s Parasitic Cosmological Argument)

Mundane primary movers may result from accidentally ordered series (non-instrumental, non-simultaneous):

"An alternative strategy is to argue that every essentially ordered causal series has a first member, where a causal series is essentially ordered if no effects within the series can exist without their causes also existing (e.g., the movement of a stone depending upon the pressure of a stick). The thought is that even if some causal series can be infinite, no essentially ordered can be. A proponent of this strategy faces the challenge of explaining why a first cause in an essentially ordered series could not have been caused by things within a non-essentially ordered causal series." (Joshua Rasmussen - Cosmological Arguments from Contingency)

Aristotle himself gives an example for an accidentally (non-essentially) ordered causal series:

"As, when something has caused motion in water or air, this moves another and, though the cause has ceased to operate, such motion propagates itself to a certain point, though there the prime mover is not present[.] [464a1] [5]" (ARISTOTLE - ON DIVINATION IN SLEEP)

Here is an alternative translation:

"When something has moved a portion of water or air, and this in turn has moved another, then even when the initial impulse has ceased, it results in a similar sort of movement continuing up to a certain point, although the original mover is not present." (Filip Radovic - Aristotle on Prevision through Dreams)

In such an order, not all members need to coexist (e.g. the father and his begotten son).

Feser's example of the proof of God originally comes from Aristotle:

"The example [Aristotle] most often gives—a man using his hands to push a spade to turn a stone—suggests a series of simultaneous movers and moved. We may agree that there must be a first term of any such series if motion is ever to take place: but it is hard to see why this should lead us to a single cosmic unmoved mover, rather than to a multitude of human shakers and movers. […] Aristotle himself at one point seems to agree with this objection, and to treat a human digger as a self-mover (256a8)[:]" (Anthony Kenny – A New History of Western Philosophy)

"e.g. the stick moves the stone and is moved by the hand, which again is moved by the man; in the man, however, we have reached a mover that is not so in virtue of being moved by something else." (Aristotle – Physics)

Elsewhere Aristotle wants to rule out self-movers:

"The basic principle of Aristotle’s argument is that everything that is in motion is moved by something else. At the beginning of book 7 of the Physics he presents a reductio ad absurdum of the idea of self-movement. A selfmoving object must (a) have parts, in order to be in motion at all; (b) be in motion as a whole, and not just in one of its parts; and (c) originate its own motion. But this is impossible. From (b) it follows that if any part of the body is at rest, the whole of it is at rest. But if the whole body’s being at rest depends upon a part’s being at rest, then the motion of the whole body depends upon the motion of the part; and thus it does not originate its own motion. So that which was supposed to be moved by itself is not moved by itself [...]. This argument contains two fallacies." (Anthony Kenny – A New History of Western Philosophy)

These are the fallacies:

"First, it equivocates between logical and causal dependence, as Sir David Ross points out in his commentary on Physics 242a 38: ‘the motion of the whole logically implies the motion of the part, but is not necessarily causally dependent on it’. (Ross, p. 669). Secondly, it equivocates between being a necessary condition and being a sufficient condition. The part’s being at rest is a sufficient condition for the whole’s being at rest; from this it follows only that the motion of the part is a necessary condition for the motion of the whole, and not that it is a sufficient condition for it. Hence the argument in no way proves that something else, namely the motion of the part, is a causally sufficient condition for the motion of the alleged self-mover. So the reductio ad absurdum fails: it has not been shown that there cannot be a body which can initiate its own movement without external causal concurrence." (Kenny, Anthony - Five Ways)

Self-motion could be explained in the following way:

"In fact, the First Way cannot deny that there are non-processes that are active, because it argues to one. But in point of fact, both Aristotle and St. Thomas held that there are acts that seem to be processes and are not, and yet are not the First Mover. These are transitions of a sort, but not transitions from potency to act. The most common example they give of such a transition is that of not seeing to seeing. […] This type of pseudo-process, then, is a transition from act to act, and the being does not acquire something that it does not already have. Another example would be actively thinking about some fact that one already knows, but was not thinking of before. One is no greater for thinking about it, because one already knows it. One could say that there is a change in some sense going on here, but it is a peculiar one, one that could be called, in modern terms, a change of phase rather than a change of state. Now such transitions are most obvious in the operations of living things, but are not confined to them. […] And this leads us back to the First Way in the light of St. Thomas’ own philosophy. Since he admits, as was said earlier, that there are transitions that are not processes, then all the First Way really argues to in Thomism is to a living being, which is defined as one which can set up its own process. (Summa Contra Gentiles, IV, c. 20.) Of course, the living being does not "move itself" (movere se) in the respect in which it is in process, but processes like growth or movement of the limbs are initiated from the soul, or the “first act” within the being, and so have as their cause one of those transitions from act to act." (George A. Blair – Another Look at St. Thomas' "First Way")

Here, as an example, is a consideration where the mind moves the body:

"The [mind] is an entity and yet not a “res . . . ,” because it is the complete dynamism of [a] substrate-less absolute change [keyword: stream of consciousness as inner motion].“ […] As an entity of time [the mind or subject] would then be precisely the form of motion of a body. For as the subject in a form of one, namely, its own body, the subject would be exactly that which through itself as that completely special type of constant motion would place its body in motion or at rest: already as a cognizing, and thus first and truly as an acting subject." (Gerold Prauss - The Problem of Time in Kant)

The mind would appear on the basis of a highly complex organized body. One would also have to say that it would emerge from the body in an entirely natural way.

Natural motions, according to current theoretical physics, generally do not require continuous causation:

"Most important for our purposes, the whole structure of Aristotle’s argument for an unmoved mover rests on his idea that motions require causes. Once we know about conservation of momentum, that idea loses its steam. [...] There is conservation of momentum: the universe doesn’t need a mover; constant motion is natural and expected. [...] The universe doesn’t need a push; it can just keep going." (Carroll, Sean - The big picture)

There are philosophical explanations for this:

"Some Thomists claim that the crucial fact which the First Way seeks to explain is not the tendency which a heavy body has to fall — this, they admit, is something which was given to the heavy body by whatever it was in the past which made it heavy — but rather the current exercise of that tendency in actual motion. Every such potentiality of a creature, they say, needs to be actualized by the immediate action of the Creator. This seems to be a piece of nonsense. To say that something has a tendency to move is precisely to say that unless something interferes, it will move; if it moves therefore, when interference is removed, no further explanation of its motion is called for apart from the tendency and the removal of the interference." (Kenny, Anthony - Five Ways)


"But it seems that at least things in perpetual motion could be self-movers. It seems, in Aquinas’s Aristotelian terms, that they could be at every moment things actually in motion and potentially in motion in the immediate future, their changing potentialities being continuously actualized by the action of their immediately antecedent actualities." (Jordan Howard Sobel - Logic and Theism Arguments: For and Against Beliefs in God)

The effect of gravity ends with large masses, which themselves would be nothing but mundane primary movers:

"Einstein had the brilliant observation that gravitational attraction was actually an illusion. Objects moved not because they are pulled by gravity or the centrifugal force but because they are pushed by the curvature of space around it. That’s worth repeating: gravity does not pull; space pushes. […] For example, you might be sitting in a chair right now, reading this book. Normally, you would say that gravity is pulling you down into your chair, and that is why you don’t fly off into space. But Einstein would say that you are sitting in your chair because the Earth’s mass warps the space above your head, and this warping pushes you into your chair." (Kaku, Michio - The God Equation)

Thus, large masses move (curve) the space and the space moves smaller masses in the direction of the larger masses.

One could identify two kinds of potential in Aristotle:

"My proposed interpretation will be based upon introducing [a] double feature of potentiality as a basic tenet of Aristotle's physics. I'll argue that there are two distinct kinds of potentials, the one consisting of potentials that are marked by their being logically entailed by the given existence of the actual, and the other, of potentials that are merely suggested by similarity or inductive considerations. The ontological difference between them is that whereas the entailed potential is fully effectual [...], the analogical or inductive potential is merely a necessary condition and thus necessarily ineffectual. [...] I'll use the terms "genuine" and "nongenuine" respectively to refer to these two modes of potentiality." (Zev Bechler - Aristotle's Theory of Actuality)

Nongenuine potentials

"are nonreal things." (Zev Bechler)

Genuine potentials, on the other hand,

"can be movers[.]" (Bechler)

This follows from all:

"[T]he proof of the necessity of a first unmoved mover is destroyed: No such mover is needed, nor de facto exists in the natural motion of the elements, where only the genuine potential is the mover. Hence the cosmic chain of mover-moved breaks down at each case of continuous natural motion, that is, of both living things and the five elements." (Bechler)

In the face of all these counterarguments, Feser turns the First Way into a composition argument as a way to save it. However, Feser is not the first to do so:

"In an attempt to vindicate the celebrated "Five Ways," John Lamont tries to show that Aquinas's arguments for an uncaused cause are successful provided they are understood as resting on an argument from composition.' Lamont further seeks to show that an uncaused cause must be immaterial and unique. In this paper, however, I shall argue that even if we accept the translation of Thomas's various proofs into an argument from composition, such an argument need in no way be thought of as implying the existence of an uncaused cause. Further, I shall show that Lamont's argument for the immateriality of the uncaused cause is problematic and his argument for its uniqueness unconvincing. [...] To sum up: Lamont, following Peter Geach, tries to show that Aquinas's proofs for the existence of God can be construed as a valid composition argument. I have argued that insofar as we can reduce the Five Ways to a composition argument, such an argument in no way yields the desired conclusion. The failure of Lamont's attempt is explained by the fact that he makes the proof of God's existence into a deductively valid composition argument only by begging the question with respect to the fundamental issue, namely, that the sum of all effects is really a group in need of a singular cause different from the causes of any of the effects of which it is the aggregate. Finally, inspection of Lamont's reasons for arguing in favor of God's immateriality and uniqueness reveals that such attributes could be seen to be validly predicated of God only by excluding alternative hypotheses which Lamont does not even envisage." (ANTOINE COTE - THE FIVE WAYS AND THE ARGUMENT FROM COMPOSITION)

The big problem is that Feser basically does not believe in the ontologically prior efficacy of parts at all:

"For example, if a stone is a true substance, then while the innumerable atoms that make it up are real, they exist within it virtually or potentially rather than actually. What actually exists is just the one thing, the stone itself." (Edward Feser – Aristotle's Revenge)

To this must be added the following:

"[S]ince (per one of Feser’s premises) only actual things can actualize something’s potential for existence, it follows that the parts Feser adduces cannot causally actualize the existence of the substances they compose." (Joseph C. Schmid - Existential inertia and the Aristotelian proof)

Hence, Feser thinks holistically, and that amounts to:

"According to holism, the table in front of you does not derive its existence from the sub-atomic particles that compose it; rather, those sub-atomic particles derive their existence from the table." (Philip Goff - Is the Universe a conscious mind?; the example of the table is probably meant only illustratively, because artifacts are usually real reductionist composites)

This means that parts cannot cause the whole, which is contrary to the point the composition argument is trying to make.

It is true that every chemical substance is divisible. But the substance does not consist of parts before a division, it is not an aggregate of parts, because the parts become actual only in the division itself. When the parts thus obtained are brought together under very specific conditions, the original whole in which the parts are "dissolved" is again created. An illustrative example would be a larger drop of water floating in a space station. One can divide the drop into two partial drops and put these parts together again into a single drop without being able to say of this one that it is now composed of two parts, which is obviously nonsensical. It has no parts, holistically speaking, only aspects and properties. Water can also be split chemically into oxygen and hydrogen. But both were only potentially in the water. And through the process of electrolysis or water splitting, they are actualized. Conversely, water can be made from oxygen and hydrogen (in a risky and expensive way). The holism is in these cases in no way harmed.

Here, the holism of an animal is presented taking a leopard as an example:

"A leopard is self-moving because the action of one part of it, the brain, which is an action of the leopard, moves another part of it, the legs, which is a movement of the leopard. […] I mean we think of the leopard as the natural unit of which the legs and brain are essentially parts; being a part-of-the-leopard is what it is for the leg to be what it is; it has its existence as what it now is by being a part of the leopard. The whole leopard, so to say, comes first. The parts are secondary. If the leg ceases to be part of the leopard it will turn into something completely different, as mutton is something completely different from a sheep. So a leopard is alive because it has organs which exist as what they are precisely by being organs, being functioning parts of a prior whole." (Herbert McCabe - On Aquinas)

Here is a summary of Aristotelian holism, which says that substances, i.e. substantial wholes, are (ontologically) prior to their "parts," since, according to Aristotelians, the parts of a substance get their identity and existence from their functions within the substance:

"[...] [A] natural object (e.g., a piece of the element earth, or water, or a plant, or a living organism) is absolutely whole, absolutely a unity. Not even what we would normally call the parts of such a natural substance (e.g., the legs of the cow) are actual parts. They are merely potential parts (i.e., the cow is not composed of them), and the moment they become actual parts they stop being really the same things. A separate leg is no leg at all, Aristotle would say." (Zev Bechler - Aristotle's Theory of Actuality)

Intuitively, one rightly assumes that once holistic things begin to exist, they will persist for some time:

"I say that [a] chair’s existence at t + ε is fully explained by the actualization of the potential, possessed by the chair at t, to continue to exist through t + ε, and the absence of anything that intervenes to prevent the realization of this potential." (GRAHAM OPPY - On stage one of Feser’s ‘Aristotelian proof’)

One can add that

"most things naturally tend to remain in existence." (Anthony Kenny - Medieval Philosophy)

Feser is at least a reductionist in his God-proof reconstruction and therefore must assume simples that God generates and moves so that they can move everything else in the world. If the transcendent God is the first member of the causal series, then something physically indivisible must stand in the second place (but in the first place within the immanence), because otherwise it would not be at exactly that second position. Doesn't God then seem completely superfluous and can't we save ourselves the incredible leap to the transcendent?

For to

"[j]ump from a first immanent cause to a first transcendent cause appears [it doesn't only appear so] to be one of the most questionable moves in the Thomistic program." (Edward N. Martin – Infinite Causal Regress and the Secunda Via)

Yet even more baffling, Feser

"offers us the explanation that God is the first transcendent cause, which, given God’s eternality and immutability, is prima facie [but not only prima facie] very hard to accept." (Edward N. Martin)

Immanent (fundamental or elementary) particles would thus suffice to account for everything under the plausible assumption of naturalism. If one sees a barely surmountable difficulty regarding the hard problem of consciousness, then naturalistic panpsychism (Philip Goff) or naturalistic dualism (David Chalmers) could be helpful additional presuppositions.

A further remark shall be made here to the particles which would be indivisible atoms of matter without further substructure (all of a piece), having absolute cohesion of their homogeneous minimum extension, which could only be misunderstood by mathematical minds as a sum of discrete parts:

"[E]ven though [the particles] have spatial extent, the question of their composition is without any content." (Brian Greene - The Elegant Universe; Greene has spoken here of strings as fundamental particles)

Aquinas also seems to agree with this in some way:

"For example, in his commentary on Aristotle's Physics, Aquinas writes of natural minima that, “although a body, considered mathematically, is divisible to infinity, the natural body is not divisible to infinity.”"

One can also grant the Thomists a certain version of a hylemorphism, if it absolutely must be.

It would be a concrete, naturalistic hylemorphism. Form and matter of a particle would not be like two heterogeneous, abstract things, which would have to be put together awkwardly by a god. There would be a natural duality of two aspects, form and matter, within the absolute unity of the particle. The aspects would be similar in nature in a certain sense (both forms of energy), whereby the matter would be something like dammed up, potential energy of a rest mass and the form would be something like an electromagnetic field energy, which arises from the matter, constantly originates and passes away and therefore can "move" the matter smoothly and continuously and produce complex stuff.

Here is a similar description:

"The form, or nature, or essence, is some definite component sitting inside the matter but distinct from it in a simple, physical sense, like the balloon from the helium it contains. [...] Aristotle's forms are not parts or components within the object because, being aspects, they are not the kind of thing that can compose their object." (Zev Bechler - Aristotle's Theory of Actuality)

Form and matter would necessarily always go hand in hand, and they would have always existed and will always exist, at all times constituting the indissoluble unity of a particle, all without loss of energy. Nothing supernatural at play. And perhaps only in our mind, that is, only conceptually, the particle has a dual aspect nature, but extramentally, that is, in reality, it is probably one in a strict sense.

A physical field is, in principle, a modern equivalent of the Aristotelian form. The fields can move matter, i.e. account for the motion of particles in a certain direction. 

Moreover, they are perhaps not essentially different from matter, which should deeply satisfy every naturalist: 

"[Fields] can be regarded as the fifth state of matter (solid, liquid, gas, and plasma are the other four states of matter)." (Marc Lange - An Introduction to the Philosophy of Physics)

Physical fields could also help to understand the mind:

"Standard neuroscience investigates how neuronal processing works. But it has problems explaining the mind’s qualia, unity, privacy, and causality this way. For example, it isn’t clear about why colours and other qualia are processed so similarly yet experienced so differently, how colour and shape information unite in visual processing, and how abstract information, concrete brain activities, and private experiences are causally and ontologically related given their radical differences.
Field theories of mind try to avoid such problems by turning from neurons to their fields. Here minds typically get their unity from the continuous nature of the fields generated by discrete neurons, while different qualia arise from different structures in the fields. These qualia are private (not publicly accessible) either because they’re non-physical or because they’re the underlying nature of fields (hidden behind what instruments and reflected light show). Mind–brain causality is (in the simplest field theories) just field–brain causality. Field theories offer new ontological approaches to dualism’s problematic causality and reductionism’s explanatory gap. Field theories face their own problems, but they’re progressively improving upon each other (see Table 1). These theories can’t be easily dismissed, for they’re based on considerable evidence and they offer powerful ways of dealing with standard neuroscience’s deepest problems." (Mostyn W. Jones – Electromagnetic-Field Theories of Mind)

Back to the particles. A subject would distinguish them purely spatially, making the spatial properties less attached to the particles than to the observing or conscious subject. Kant gives a good example of mere extrinsic distinctiveness:

"Take two drops of water, and set aside any intrinsic differences (of quality and quantity) between them; the mere fact that they have been intuited simultaneously in different locations justifies us in holding that they are numerically different, i.e. that they really are two drops. (Immanuel Kant - Critique of Pure Reason up to the end of the Analytic)"

I have described extended particles, but there are also point-like particles in physics which have similarities with Leibnizian monads:

"A point particle (ideal particle or point-like particle, often spelled pointlike particle) is an idealization of particles heavily used in physics. Its defining feature is that it lacks spatial extension; being dimensionless, it does not take up space." (


"In summary, extended particles have a fixed size, although they may have a fuzzy edge; point-like particles are mathematical abstractions with zero size. But even zero-size particles have an extended effect, due to the effect of the field surrounding them." (

The attempt to save Aquinas' proof by making it a composition argument fails. The supposed saviors want to say: parts compose (move) the whole and these parts are composed by further parts and this cannot go to infinity and must end with God. I say that this is refuted by holistic wholes or fundamental particles or even point-like particles. Feser's reconstruction of the First Way to God is therefore not convincing.

If he would say that it is not only about the local movement (locomotion), when the Thomists speak about motion, then this would strike me as problematic. After all, Feser wants to talk to non-Thomists and convince them. Therefore, for a successful discussion, he should assume only two kinds of movement, locomotion and mental inner change (stream of consciousness in terms of successive thoughts, feelings and moods), which the non-Thomist has no problem to accept. As far as the locomotion is concerned, which Feser himself has given as an example, he has not succeeded, as I hope to have shown, in giving a proof of God.

Finally, it should be noted that the Thomists, when they talk about wholes and parts, in a very one-sided and narrow-minded way, know only complete independence of a thing (God) or only complete dependence (creation) on a thing (God). There is nothing in between. But it is not difficult to envisage a semi-independence of the things of the world. And to think of the stuff of the world (or some of it) as being independent, perhaps only dependent on quantum stuff, doesn't seem too hard either.

The quantum stuff would be the most fundamental building block or component of all things:

"It's beginning to look as if everything is made of one substance-call it "quantumstuff"-which combines particle and wave at once in a peculiar quantum style all its own. By dissolving the matter/field distinction, quantum physicists realized a dream of the ancient Greeks who speculated that beneath its varied appearances the world was ultimately composed of a single substance. Some philosophers said it was All Fire; some All Water. We now believe the world to be All Quantumstuff. The world is one substance." (Nick Herbert - Quantum Reality: BEYOND THE NEW PHYSICS)

Why Feser's ethical natural law (regarding sexual activity) does not work:

"[It] is hard to see […] why facts about the natural functions of the reproductive organs are even morally relevant, let alone morally decisive. To suppose they are morally decisive is to suppose that there can be cases in which the intentions of agents are irrelevant to the moral worth of an act. It is to repose the moral worth of those acts in their physical properties." (Weithman, Paul J. - Natural Law, Morality, and Sexual Complementarity)

"John Montgomery Cooper [a Catholic moral philosopher] was himself not wholly persuaded by the natural law argument, at least as a proof that contraception was mortally sinful. "Just precisely how are we going to formulate such a definition of the natural function of the reproductive faculty as will permit relations in pregnancy and sterility and yet bar contraceptive practices?" he wanted to know. "And after we have succeeded – if we succeed – in so formulating this function, just precisely what concrete objective evidence are we going to muster to show that our formulation, and no other, represents the true function?" (Leslie Woodcock Tentler - From Catholics and Contraception An American History)

"Cooper targeted the deductive “perverted faculty” argument by saying that Catholic authorities have offered “facile assumptions” in place of “objective evidence” as to “what precisely is the natural function of the faculty (sex) under consideration?”" (Alexander Pavuk - Catholic Birth Control?)

"Even if it is conceded that procreation is the obvious function of sexuality, it is far from clear that it should be the only, or the indispensable, function of human sexuality." (Robin Gill - A Textbook of Christian Ethics)

"For instance is the purpose of a mouth for eating or for kissing or for both? Who is to decide? If kissing is part of the function of mouths, then kissing would become a good rather than, arguably, an evil. The need to make assumptions which may be challenged is, therefore, implicit in Aquinas’ whole approach and weakens its effectiveness." (Vardy, Peter. The Puzzle of Ethics)

Feser's version of Thomistic natural law operates with the terms "in contrary to" and "other than". For systematic reasons, the term "in accordance with" should still be added. That is, to act contrary to the nature of any of my parts is morally evil, to act in accordance with it is morally good, and, to act other than it is morally neutral.

If I eat breakfast and take a wash in the morning, that is already morally good, because I am acting in accordance with my nature. Natural law does not make it difficult for me to be good in this case. If, among other things, the mouth and tongue are naturally there for kissing, then moral pluses can also be obtained quite easily during this sensual activity.

On the other hand, it would be morally evil, as it would be contrary to nature, if a man had to give a sperm sample for cancer diagnosis and the sample was obtained by means of masturbation. Equally morally evil would be the spermiogram, which provides a reliable indication of sperm quality in cases of suspected infertility, if the semen sample was again obtained by masturbation.

Chewing gum would be a case of moral neutrality. Because my system of food intake is only used differently (other than) compared to the normal eating and digestion process. Although chewing a nutrientless gum cheats my stomach, which is expecting real food; although my chewing motion runs into emptiness (goes nowhere and proves futile) and thus unnecessarily strains my masticatory muscles; although something that cannot be chewed up into small pieces and digested would have to be spat out immediately and should not be kept in the mouth knowingly; although I might have the provocative attitude and intention to demonstratively pervert my food intake system while chewing, gum chewing is said to be in itself morally neutral.

However, nobody has yet really figured out Feser's distinction between "in contrary to" and "other than". In both cases the natural goal is consciously not aimed at, and yet only in the case of "in contrary to" somehow something evil comes along.

Even an intellectual companion of Feser, who follows the same moral line, i.e. argues very similarly, can not make anything of Feser's distinction:

"Feser relies upon an unclear account of contrary use and other than use, which is either ad hoc or cannot grant him the conclusion he desires." (John Skalko - Disordered Actions)

If the distinction is untenable, Feser's version of natural law fails miserably. For then either trivial actions like chewing gum, walking on one's hands, supporting a broken table with one's legs would be morally bad or all actions that were previously classified as evil would be morally neutral.

"Natural moral law theorists confuse talking about what is the case with talking about what ought to be the case. They confuse dejure statements with de facto statements. A statement about what people or what normal people seek, strive for or desire is a factual, non-normative statement. From this statement or from any conjunction of such statements alone no normative (de jure) conclusions can be validly deduced except in such trivial cases as from "He wears black shoes" one can deduce "He wears black shoes or he ought to be a priest." But this simply follows from the conventions governing the disjunction "or." Moreover, because it is a disjunction it is not actually actionguiding; it is not actually normative. To discover what our natural inclinations are is simply to discover a fact about ourselves; to discover what purposes we have is simply to discover another fact about ourselves, but that we ought to have these inclinations or purposes or that it is desirable that we have them does not follow from statements asserting that people have such and such inclinations or purposes. These statements can very well be true but no moral or normative conclusions follow from them." (Kai Nielsen - Atheism and Philosophy)

You can derive an ought only from a will, to put it more precisely, from another will, a will different from one's own. The foreign will is to be understood as a (potential) request, claim, requirement, demand or command, all of which only another (rational) person can do. Since I am German, my reasoning comes from the logic and semantics of the German verb "sollen", which translates to ought or should (shall) in English. Almost all grammars of German explain "sollen" by saying that there must be another personal agent who wants something from you (who insists that you do something). So, if A ought to do X, this implies that someone wants A to do X. For example: I go to the doctor and he tells me to take two pills twice a day. Then I later tell my wife I ought to take two pills twice a day.

The ethical question that now arises is, how can I distinguish a morally binding ought from a morally non-binding ought? Because not everything that people ask me to do is really binding.

However, natural law does not get as far as this question. It already fails at the preconditions of the ought. For one thing, the organs, faculties, capabilities, powers of my body (when they are activated or in actual use) are not something, not even potentially something, that I can understand as a foreign (external and separate) personal and knowing will that wants or expects me to do something specific.

If one now says that God most personally demands certain actions from me via the way of my nature, then this form of addressing and being addressed is highly questionable. I can only say that I do not notice anything at all of God demanding something from me by means of my nature, and this is not consistent with His perfection. Surely, when it comes to actions of great moral significance, assuming God existed and decreed natural law, He would not hide.

Especially if one is a convinced philosophical skeptic, perhaps a Humean, who thinks the following, then God must do a better job of making his natural law will known to all mankind:

"The so-called 'laws' of the natural sciences originate in man's preference for order, but not from nature itself. There is nothing corresponding to them in nature. The same criticism applies to the concept of 'aim' in nature, which M[authner] takes, with Spinoza, to be only an analogy to human intention." (Gershon Weiler - On Fritz Mauthner's Critique of Language)

But in fact, the ought in natural law is merely the personal (conservative) will of the natural lawyers:

"As I’ve said, natural laws and natural rights are inventions intended to advance the interests of the inventors (whom I shall call “natural legislators”). What is often involved is an attempt to manipulate other people into behaving as desired by a natural legislator, by duping them into accepting the values of the natural legislator as the values of nature. Thus, the personal, subjective preferences of a natural legislator are passed off as the impersonal, objective requirements of nature. For example, Frederick D. Wilhelmsen writes that, “Natural law insists that pornography … is bad and that it is bad not just for me, but for everybody, and it equally insists that not only must I not invade my neighbor’s property but that he must not invade mine or anybody else’s.” In other words, Frederick Wilhelmsen insists that pornography is bad for everybody, and he equally insists that no one must invade anybody else’s property. But in order to give his personal preferences greater authority, Wilhelmsen pretends that it is nature who is doing all the insisting." (L.A. Rollins – The Myth of Natural Rights)

I have come to the conclusion, and there is no doubt in my mind, that Thomistic natural law is not only dependent on a belief in God or believing in the validity of a proof of the same, but above all that it is dependent on a belief in the Catholic Church and its teachings and in the fact that these teachings have been "dictated", so to speak, by the Holy Spirit. Without such belief, natural law hangs in the air as an indeterminate, indefinable theoretical something. For the speechless, silent and dumb nature I can interpret in many ways; and that it addresses to me a moral ought, is something the church has to tell me. Natural law is thus not only theologically but also denominationally bound. Therefore, it is not convincing in purely philosophical terms.

The gay Aquinas expert Mark D. Jordan confirms my thesis:

"[...] Thomas knew as well as any medieval theologian that human societies disagree sharply about how human beings ought to act. He himself mentions cases in which whole societies teach their members to do things that he thinks contrary to natural law. Given the diversity of societies, the contradictions in the history of moral conventions, is there any kernel of natural law that every human being shares? Perhaps there is, but that kernel will not be enough to direct us individually or to make us agree collectively. In practical matters, agreement about principles and about the shape of moral reasoning is no guarantee of agreement about practical conclusions. Indeed, the more particular the case, the more difficult it is to arrive at a conclusion on which all will agree. Alternately, the more specific a norm or precept proposed in ethics or law, the more liable it is to justified exception. In many particular cases, the right course of action cannot be regularly agreed, even among virtuous people.
This insufficiency of natural law becomes the starting point for Thomas's arguments in the Summa on the need for divine law, that is, for an explicit teaching about human conduct revealed by God. Because natural law participates in God's eternal plan only "according to the proportion of the capacity of human nature," God generously teaches a more articulate law, the divine law that is eminently contained in the Old and New Testaments. We are able to "fulfill" the natural law only after God's revelation. The content of natural law only becomes clear with the handing down of the Old Law, the law of Moses. The content of natural law only becomes practicable with the gift of grace in the New Law - whether we are talking about justice or about "unnatural" sex.
Many of the "natural law" arguments we hear today do not rise to the level of misreadings of Aquinas. They are rather loud assertions pretending to be common sense or, what is worse, natural science. But even in more serious efforts to make "natural law" arguments against certain sexual acts, we can hear how easily Christian theology can slip from rich conceptions of law as divine self-disclosure to poor conceptions of law as imposed ideology or criminal code.


The difficulty we now feel in speaking convincing arguments about "unnatural" sex cannot be blamed on just the growth of modern medicine or the spread of liberal notions about self-fulfillment. We understand it better as a loss of the grand Christian rhetorics within which sin-identities made sense of acts by organizing them. When we try to pull the acts away from the identities, we find that they don't make much sense. Of course they don't. They never did without identities.
This loss of coherence in specifying "unnatural" acts is closely connected to the loss of conviction produced by appeals to natural law. Christian condemnations of unnatural acts were not meant to work without Christian sin-identities; arguments from natural law were not meant to work outside of an ideal pedagogy of virtuous family, just city, and luminous divine revelation. Natural law arguments about sex are not detachable from the Christian narrative of a progressive divine teaching through history." (Mark D. Jordan - The Ethics of Sex)

If the theory of evolution is correct, then at least in the organic world there are no metaphysically fixed Aristotelian forms with respect to supra-individual animal or plant species. A squirrel, for example, with all its abilities and qualities, would be a product of mercilessly brutal natural selection. And each generation of squirrels might undergo a minor or major change over time, which in turn would affect the succeeding generation. Change would be an integral part of the generational transition, and thus of squirrels themselves. Finally, man has evolved evolutionarily (and this evolution has not exactly covered itself with moral glory), so that we can no longer speak of a metaphysical species of man, but only of a biological one in a rather loose sense. We thus lose the general form of man (which supposedly includes only heterosexuality) as a supra-temporal ethical template. When it comes to morality, one can ask either way how nature (of man) in its organic (also mental) constitution can be a fixed and credible standard for moral action at all (Feser assumes this, after all), if it is demonstrably subject to a constant amoral evolutionary process? The rigid, fixed nature in natural law and the fluid nature in evolutionary theory (no matter how slow nature may be), that simply does not fit together. In the world of evolution, there are only individual living beings ("egoistic" genes with their survival machines), between all of which there are only degrees of (blood) relationship in the tree of life. Evolution does not only concern the outer shape of a living being (only this Feser seems to have in mind in terms of natural law, whereby he also only sees what he wants to see), but also its behaviors and inner dispositions or inclinations (in the case of humans, evolutionary psychology deals with this subject), all of which, if one plays along with the game of a certain natural law (that of Feser), must be included in the assessment of the biological functionalities.

Here are also once more remarks to natural law with regard to biological evolution:

"First, it is no part of a modern notion of functionality that a function is unique. Some organ may well be involved in different uses, each of which gives, or has given, its possessor an evolutionary advantage. In particular, then, the mere fact that the genitals are involved in conception does not mean that they do not have other important functions. It is not incredible to suppose that the giving and receiving of pleasure is one of these. [...] Second, and relatedly, behaviour patterns traditionally reckoned as perverse are hardly modern ones. They are long-standing and widely spread th[r]ough sections of the population. [...] This suggests (though, of course, it by no means proves) that at least some of them may well have been selected for evolutionarily. If such a behaviour pattern is genetically based, this is, presumably, the case. Notoriously, for example, some sociobiologists have argued that homosexuality is a genetic disposition, and that homosexuality makes perfectly good sense as a strategy for facilitating certain gene transmissions. I certainly do not want to endorse the sociobiological account of homosexuality. I mention it simply to demonstrate that in the light of modern science, it makes perfectly good sense for things counted traditionally as perversions to be functional. Third, and again relatedly, according to both accounts that we looked at, a functional trait may cease to give an evolutionary advantage if the environmental context changes: witness the dinosaurs. (According to the dispositional account, the trait in question then ceases to be a function.) Now, one of the most salient features of the current human environment is the imminent threat of over-population and the consequent environmental disaster. Such an event would doubtless have consequences for the human gene pool - possibly even destroying it. Hence, assuming that it is unrealistic for most people to become celibate, increasing non-procreational sexual activity may well be an evolutionarily sensible strategy in the present context." (Graham Priest - Sexual perversion)


"[T]here is nothing wrong per se with using something for other than its Darwinian biological function. For example, whether one gives an aetiological or a dispositional account of function, body hair may plausibly be supposed to have various functions (protection from the sun, holding body-secretions close to the skin). Yet there is nothing wrong with shaving one's head or armpits and using the hair for something else. Similarly, a function of certain body secretions is to form an infection-protective coating for the skin; but there is nothing wrong with washing frequently (and using the secretion-infused result to water the flowers)." (Graham Priest - Sexual perversion)

An important component for natural law was the ancient valuation of male semen, which had long been recognized as wrong:

"Aquinas is often invoked in contemporary discussions of the morality of contraception and abortion. In fact, he had very little to say on either topic. Contraception is discussed, along with masturbation, in a question in the Summa contra Gentiles concerning ‘the disordered emission of semen’. Aquinas maintains that this is a crime against humanity, second only to homicide. This claim rests on the belief that only the male provides the active element in conception, so that the sperm has an individual history continuous with the embryo, the fetus, and the infant. In fact, of course, male and female gametes contribute equally to the genetic constitution of the eventual human being. An embryo, unlike the father’s sperm or semen, is the same individual organism as an infant at birth. For Aquinas, the emission of semen in circumstances unsuitable for conception was the same kind of thing, on a minor scale of course, as the exposure or starvation of an individual infant. That is why he thought masturbation a poor man’s version of homicide." (Anthony Kenny – Medieval Philosophy)

"For Thomas, every sexual act has to be a marital act, and every marital act has to be an act of procreation. A violation of the sexual commandments is a violation of life itself. For the semen already contains the potential for the whole person (or, more precisely, the whole man, for women come into being only when something goes awry in the process of development; De malo 15 a. 2). The unregulated ejaculation runs counter to the well-being of nature, which lies in the preservation of the species. Therefore, after the sin of murder, through which human nature, which already exists in reality, is destroyed, the sin of preventing the generation of human nature comes in second place" (Summa Contra Gentiles III, 122). Contraception is thus not the same thing as murder, but is very close to it. Along with Aristotle, Thomas calls semen "something divine" (De malo 15, 2)." (Uta Ranke-Heinemann - Eunuchs for the Kingdom of Heaven. Women, Sexuality and the Catholic Church)

To this we can add:

"[I]t cannot be a moral duty to ensure the continuation of the species, as is so frequently argued. This excuse is such an obviously barefaced lie that I hesitate to make a fool of myself by asking whether any human being has ever performed sexual intercourse with the thought of having to avert the great danger of the demise of humankind, […] and nobody who asks himself sincerely will feel it to be his duty to ensure the continuing existence of the human species. But what is not felt to be a duty is not a duty." (Otto Weininger - Sex And Character An Investigation Of Fundamental Principles)

For me personally, the strongest argument against natural law in sexual terms is this:

"It may also be argued that Aquinas’ approach is not holistic – it fails to consider the human being as a psycho-physical unit. To separate, for instance, genitalia out as having a particular purpose on their own without considering the whole complexity of a person’s relationship to his or her body, psychology, sexuality in general, the ability of human beings as embodied persons to express and receive love and to come to their full humanity may be a diminution of human beings as people. We are not an accumulation of ‘bits’ – we are whole human persons and all moral judgements must take our complexity as human persons into account." (Vardy, Peter - The Puzzle of Ethics)

Even if, like Feser, one is a proponent of the Old Natural Law, one need not necessarily classify homosexual acts as immoral. For there is much to support the view that human homosexuality, like that which occurs in many animal species, is natural and is felt by the majority of those practicing homosexuality to be healthy:

"[I]t is still worth remarking that sexually inverted people can otherwise be perfectly healthy and, apart from accessorial social factors, do not feel worse than all the other healthy people. If one asks them whether they have any wish to be different in this respect, one quite often receives a negative answer." (Otto Weininger - Sex and Character: An Investigation of Fundamental Principles)


"I think that perversions, if there are any such things, are either sexual manifestations of various aspects of bad moral character or states that are psychologically inextricable from bad moral character. I am myself unsure whether there are any sexual perversions. [...], I am very confident that the psychological generalisations that have underwritten the claim that homosexuality is a perversion are false." (Dirk Baltzly - PERIPATETIC PERVERSIONS: A NEO-ARISTOTELIAN ACCOUNT OF THE NATURE OF SEXUAL PERVERSION)


"Whether a sexual activity is natural or perverted does not depend [...] on what organs are used or where they are put, but only on the character of the psychology of the sexual encounter." (Alan Soble - Philosophy of Sexuality)

Homosexuals then simply belong in a "subcategory":

"Many prominent proponents of Old and New Natural Law morally condemn sexual acts between people of the same sex because those acts are incapable of reproduction; they each offer a distinct set of supporting reasons. While some New Natural Law philosophers have begun to distance themselves from this moral condemnation, there are not many similarly ameliorative efforts within Old Natural Law. I argue for the bold conclusion that Old Natural Law philosophers can accept the basic premises of Old Natural Law without also being committed to morally condemning sexual activity between people of the same sex. I develop an argument from analogy that shows how we can draw metaphysically distinct subcategories based on someone’s capacity to experience the unitive goods of sex. This unitive capacity constitutes the sub-category and provides a distinct principle for evaluating how members of that sub-category (X) act as members of that sub-category, rather than as acting as defective members of another category (Y). Even though my argument is ‘internal’ to Old Natural Law, I conclude by showing how these conclusions can also address some of the objections to same-sex sex in New Natural Law." (KURT BLANKSCHAEN - Rethinking Same-Sex: Sex in Natural Law Theory)

The knowledge of what natural law is changes over time, without having to be completely overturned if one wants to be a Catholic and to accept natural law as a guide to action at all:

"When Catholics embrace the essentially eschatological and therefore unfinished character of the process of natural law knowledge, they realize that the reliability of the tradition is neither destroyed nor diminished by its errors. In this way, the discovery of the humanity of homosexuality does not overturn the authority of the man who once condemned it. Heterosexual Catholics need no longer fear the ecclesial inclusion of lesbians and gays while lesbian and gay Catholics need no longer fear the Thomistic texts that have been so expertly used against them. Misrepresented as an author who underwrites magisterial terror, Aquinas reveals himself to be a source of lesbian and gay Catholic empowerment." (Katie Grimes - BUTLER INTERPRETS AQUINAS: How to Speak Thomistically About Sex)

Here is a summary account of Catholic historicity regarding the condemnation of contraception (after all, the rhythm method as a contraceptive is allowed, which apparently was not always the case):

"The recorded statements of Christian doctrine on contraception did not have to be read in a way requiring an absolute prohibition. The doctrine had been molded by the teaching of the Gospels on the sanctity of marriage; the Pauline condemnation of unnatural sexual behavior; the Old Testament emphasis on fertility; the desire to justify marriage while extolling virginity; the need to assign rational purpose and limit to sexual behavior. The doctrine was formed in a society where slavery, slave concubinage, and the inferiority of women were important elements of the environment affecting sexual relations. The education of children was neither universal nor expensive. Underpopulation was a main governmental concern. The doctrine condemning contraception was formulated against the Gnostics, reasserted against the Manichees, and established in canon law at the climax of the campaign against the Cathars. Reaction to these movements hostile to all procreation was not the sole reason for the doctrine, but the emphases, sweep, and place of the doctrine issued from these mortal combats. The environmental changes requiring a reconsideration of the rule accumulated only after 1850. These changes brought about a profound development of doctrine on marriage and marital intercourse: love became established as a meaning and end of the coital act. Before women were emancipated and marriages in the West came to be based on personal decision, writing like that of Von Hildebrand, Doms, Haring, Suenens, Fuchs, Ford, and Kelly would have seemed chimerical. Their work responded to the change in conditions. Their teaching on marriage was in many ways different from that of older theologians. Huguccio would have marveled at the teaching of Ford and Kelly, Jerome would have been astounded at Haring. Suppose the test of orthodoxy were, Would Augustine or Thomas be surprised if he were to return and see what Catholic theologians are teaching today? By this criterion, the entire development on the purposes of marital intercourse would have been unorthodox. But it is a perennial mistake to confuse repetition of old formulas with the living law of the Church. The Church, on its pilgrim's path, has grown in grace and wisdom. That intercourse must be only for a procreative purpose, that intercourse in menstruation is mortal sin, that intercourse in pregnancy is forbidden, that intercourse has a natural position - all these were once common opinions of the theologians and are so no more. Was the commitment to an absolute prohibition of contraception more conscious, more universal, more complete, than to these now obsolete rules? These opinions, now superseded, could be regarded as attempts to preserve basic values in the light of the biological data then available and in the context of the challenges then made to the Christian view of man. At the core of the existing commitment might be found values other than the absolute, sacral value of coitus. Through a variety of formulas, five propositions had been asserted by the Church. Procreation is good. Procreation of offspring reaches its completion only in their education. Innocent life is sacred. The personal dignity of a spouse is to be respected. Marital love is holy. In these propositions the values of procreation, education, life, personality, and love were set forth. About these values a wall had been built; the wall could be removed when it became a prison rather than a bulwark." (John T. Noonan, Jr. - Contraception: A History of Its Treatment by the Catholic Theologians and Canonists)

Sonntag, 29. September 2019

Critique of Edward Feser's Last Superstition

With passion, anger, and malice, Feser presents his dyed-in-the-wool conservative (Catholic) views in The Last Superstition. Unfortunately, in this way, the book has become an extremely undifferentiated, extremely one-sided and manipulative polemic (Pied Piper or rabble-rouser writing) rather than a serious, sober confrontation of Thomas Aquinas' philosophical thoughts (which certainly should not be known to everyone) with the theses of the so-called New Atheists.

Feser's polemics don't serve the cause. In comparison, one only has to consider Aquinas' sobriety and effort not to ridicule the opponent - deserved or not - but to present him in the best possible way. So it does not speak in favor of Feser that he places himself on the same polemical level as the New Atheists, especially since he is so annoyed about their way of presenting themselves and their ideas. That's just imitating immature behavior (at least what Feser considers to be immature behavior).

I cannot recommend his book to anyone who is only very superficially familiar with philosophy. One should first be acquainted with the history of philosophy, i.e. know the debates that have been fought over philosophical problems for almost three thousand years. And it also can't hurt to know other metaphysical systems in advance, or the best atheists and agnostics out there like Walter A. Kaufmann (Critique of Religion and Philosophy, The Faith of a Heretic), Kai Nielsen (Atheism and Philosophy), William L. Rowe (Can God Be Free, The Cosmological Argument), J. L. Schellenberg (The Hiddenness Argument), John Leslie Mackie (The Miracle of Theism), Nicholas Everitt (The Non-Existence of God), Theodore Drange (Nonbelief & Evil), Michael Martin (Atheism: A Philosophical Justification), Graham Oppy (The best argument against God, Arguing about Gods), Jordan Howard Sobel (Logic and Theism Arguments) and last but not least the agnostic and Aquinas expert Anthony Kenny (The Five Ways, Unknown God, The God of the Philosophers).

For Feser is a very smart writer whose style appears upbeat, direct, self-confident and elaborate, and who is able to convince and seduce the reader by omitting information, using sophisticated rhetoric and other manipulative persuasion tricks. Any philosophically naive secularist could fall into the clutches of him and, at worst, into a state of intellectual unease and trouble.

The problem with Feser is that he cultivates a prima facie academic style, but combines it with rather wild esoteric, vague or meaningless statements. His philosophical-historical theses, e.g. on Aristotle, are more on the level of Reader's Digest and generally not tenable from an expert's point of view. One has to understand that Feser has only one agenda, namely to bring others to Catholicism or to lure them into it. If you understand that, you also understand his way of writing.

By three examples (there are many more), I will briefly explain some of Feser's manipulation strategies. For one thing, Feser talks a lot and full of admiration about Plato. According to Feser, Plato is the discoverer of the conceptual ideas, that can be understood with the help of one's reason. What Feser conceals, however, is that for Plato the grasping of ideas goes beyond reason and rationality. Plato does not believe that pure reason can be used to comprehend ideas; they can only be grasped mystically. But the mystical component would involve some irrationality. It is only a small thing, but Feser does not represent Plato one hundred percent so that his rationalistic project might not feature any philosophical blemishes, not even historical ones.

The second point is that at the beginning of his book Feser advocates a strong Platonic concept realism, which he tries to support with many arguments, only to relativize it later (paradoxically and oddly) in favor of the theory of universals proposed by Aristotle, who did not think much of Plato's Ideas. For Aristotle bids
[f]arewell to the [Platonic] Forms: they are but ding-a-lings [in other translations: jibber-jabber or trala-las] and even if they do exist they are wholly irrelevant[.] (APo. 83A32–34) 
Feser is suggesting that Platonic realism is a healthy and reasonable default position that requires little correction only. At the other end of the theoretical spectrum is nominalism, which Feser hates like the plague (because under nominalism his whole project would fail, for which in any case there would still be metaphysical non-Thomistic and non-Christian alternatives). Nevertheless, Feser could have critically proceeded from nominalism in order to arrive at Aristotle. But this path would probably not have seemed in line with his philosophical agenda, for many nominalists have also been able to invoke Aristotle for their own theories.

The last example is also about Plato. In the chapter Basic laws of nature, Feser presents two theories on how to understand the physical laws of nature. Feser now pretends that there is only one either-or between these two theories, namely between Neo-Aristotelian powerism theory and Hume's regularity theory based on the habitual correlation of events. The immature reader will, of course, tend towards the former, which Feser has made appealing, while he has unfairly ridiculed the latter. What Feser disingenuously does not mention is the third option, which is still the most widely upheld to this day. That third option contains a Platonic view of the laws of nature. Rupert Sheldrake gives a historical outline in his book The Science Delusion:
In Europe from the fifteenth century onwards there was a revival of Platonism, which helped prepare the way for modern science. The founding fathers of modern science, Copernicus, Galileo, Descartes, Kepler and Newton, were all essentially Platonists or Pythagoreans. They thought that the business of science was to find the mathematical patterns underlying the natural world, the eternal mathematical Ideas that underlie all physical reality. As Galileo expressed it, Nature was a simple, orderly system that ‘acts only through immutable laws which she never transgresses’. The universe was a ‘book written in the mathematical language’. Most great physicists expressed similar ideas. For example, in the nineteenth century Heinrich Hertz, after whom the unit of frequency is named, expressed it as follows:
One cannot escape the feeling that these mathematical formulae have an independent existence and an intelligence of their own, that they are wiser than we are, wiser even than their discoverers, that we get more out of them than was originally put into them.
Albert Einstein’s general theory of relativity was firmly in this tradition, and Arthur Eddington, who provided the first evidence in favour of the theory, concluded that it pointed to the idea th So ttioat ‘the stuff of the world is mind stuff . . . [T]he mind stuff is not spread out in space and time: these are part of the cyclic scheme ultimately derived out of it’. The physicist James Jeans took a similarly Platonic view: ‘[T]he universe can be best pictured . . . as consisting of pure thought, the thought of what, for want of a wider word, we must describe as a mathematical thinker.’
Quantum theory extended Platonism to the very heart of matter, which old-style atomists had regarded as hard, homogeneous stuff. In the words of Werner Heisenberg, one of the founders of quantum mechanics:

[M]odern physics has definitely decided for Plato. For the smallest units of matter are not physical objects in the ordinary sense of the word: they are forms, structures, or – in Plato’s sense – Ideas, which can be unambiguously spoken of only in the language of mathematics.
The traditional assumption that the universe is governed by fixed laws and constant constants is almost unquestioned.

Some theorists go even further. The cosmologist Max Tegmark proposes that any mathematically possible universe must exist somewhere: ‘Complete mathematical democracy holds – mathematical existence and physical existence are equivalent, so that all mathematical structures exist physically as well.’ There is no need to limit the mathematics to superstring theory or even any other existing mathematical system. Tegmark observes that his theory ‘can be viewed as a form of radical Platonism’. 
The reader is probably not supposed to find a taste for a Platonic or Platonist God, but to learn to appreciate an Aristotelian God. Many Platonic physicists or cosmologists even believe only in a Platonic realm without a god, since they believe in the causal efficacy of the Platonic abstracta.

It is therefore not surprising that Feser does not mention Plato's cosmological dialogue Timaeus. Here is an overview of the physical foundations in Plato's cosmology: 
Each kind of matter (earth, air, fire, water) is made up of particles (“primary bodies”). Each particle is a regular geometrical solid. There are four kinds of particles, one for each of the four kinds of matter. Each particle is composed of elementary right triangles. The particles are like the molecules of the theory; the triangles are its atoms. 
The argument that all bodies are ultimately composed of elementary right triangles is given at 53c-d: all bodies are 3-dimensional (“have depth”) and hence are bounded by surfaces. Every surface bounded by straight lines is divisible into triangles. Every triangle is divisible into right triangles. Every right triangle is either isosceles (with two 45° angles) or scalene. So all bodies can be constructed out of isosceles and scalene right triangles. (
The only thing that I can give Feser credit for is that he repeatedly points to important questions of philosophy, such as those concerning universals (truthmakers of sentences attributing properties to particulars) and teleology (questions that a philosopher or scientist cannot easily dismiss). But overall, you definitely have to attest Feser a (Catholic) mania with reason and rationality:
It is a striking feature of Feser’s book [Last Superstition] that he claims to be basing his contentions entirely on reason and not on faith. Certainly, he never explicitly appeals to any sacred text or religious teacher as an authority. But he makes extensive claims for the powers of reason. Pure reason, he tells us, proves that there is a God and that we have immortal souls. That shows that a miracle like resurrection from the dead is possible. Given this background, the evidence that Jesus rose from the dead is overwhelming. But Jesus claimed to be divine and claimed that his teachings would be confirmed by his resurrection. Hence, reason shows that he really was divine. But he was obviously distinct from the Father to whom he prayed, and the Spirit whom he sent. So reason shows the doctrine of the Trinity to be true. This is to extend the scope of natural reason much further than even Thomas Aquinas was willing to do. (Anthony Kenny - We have all been here before)
Strictly speaking, all the theological steps that Feser wants to make plausible, apart from the fact that their contents are questionable in many respects, are non-sequiturs. 

As an Aquinas expert, Feser should also know Aristotle like the back of his hand. But here he already commits a faux pas. From an arrogant attitude, he criticizes the modern secularists that, because of their narrow view on metaphysical things, they only know one kind of change, namely local movement. But Aristotle had already realized that there were other kinds of change. As an example of another, the quantitative change, Feser then refers to water that becomes warmer or colder: 
changes in quantity (like [water’s] becoming hotter or colder by degrees)[.] (Edward Feser)
This is a clear mistake - of course, the quality had changed in the example - which only a philosophy student could commit at the very beginning of his studies. Just because it is possible to express getting colder or warmer in numbers does not mean that we are dealing with quantitative change in the sense of Aristotle (e.g. if something gets smaller or larger. When water gets warmer, it naturally expands, but I don't think that's what Feser meant). The fact that something like this happens to a great admirer of Aristotle is somewhat strange. Feser also omits the important information that Aristotle in his Physics ultimately attributes all kinds of change to local movement, as the mechanistically thinking secularists have always done in principle. At least the spatial movement, which for Aristotle is the most important and primary movement, is a fundamental prerequisite for all the others. But not a word from Feser about this, not even about the fact that modern physics has already said goodbye to many mechanistic principles.

Feser makes a lot of angry fuss about the fact that the secularists would not recognize the true basis of morality, more precisely, the Platonic and Aristotelian forms. An immoral consequence of this disregard is (according to Feser) the current high number of abortions, which are carried out without hesitation and penal consequences. But Feser must make one thing clear to himself. If even the fathers and discoverers (or just inventors?) of these philosophical forms/ideas could not see that infanticide (which they have advocated under certain circumstances, especially in the case of deformities) is something absolutely reprehensible, then how can today's secularists, who are extremely superficial in Feser's eyes, do so? Consequently, Feser's anger cannot be adequately justified. 

Furthermore, as already mentioned, Feser is not always completely honest with his readers. At least he often seems to keep important information behind the scenes. In the chapter about evil, Feser says that terrible suffering in this world is basically (and universally) outweighed by eternally blissful and beatific (everlasting) visions in the hereafter:
[T]here is every reason to think that God can and will bring out of the sufferings of this life a good that so overshadows them that this life will be seen in retrospect to have been worth it. (Edward Feser)
Indeed, even the greatest horror we can imagine in this life pales in insignificance before the beatific vision. (Edward Feser)
But this quote from Feser must be supplemented by one from Schopenhauer:
But as far as the life of the individual is concerned, every life history is a history of suffering, because the course of each life is for the most part a continuous series of accidents both great and small; [...] perhaps there will never be a man who, clear-headed and sincere at the end of his life, would want to do it all again – he would much rather choose complete non-existence instead. (Arthur Schopenhauer - The World as Will and Representation)

Feser now indicates that the victims of the Holocaust (Feser specifically mentions "Auschwitz"), for example, did not suffer so much in vain and for nothing. As a Catholic theologian, however, he must honestly admit that a very painful life alone is not enough to qualify as a promising candidate for a heavenly reward. One must at least be a good Catholic, otherwise, the papal church would make no sense in the end. Feser obviously did not have the heart to say that a Jew who suffered terribly in a concentration camp and was tortured to death there probably even had to expect eternal hell. In this respect, one should look at a permanently settled result of the Council of Florence dating from 1442:
[The Holy Roman Church] firmly believes, professes and preaches, that none who are outside the Catholic Church, not only pagans, but also Jews and heretics and schismatics, can partake of eternal life, but they will go into eternal fire… unless before the end of life they will have been joined to [the Church] and that the unity of the ecclesiastical body has such force that only for those who remain in it are the sacraments of the Church profitable for salvation; and fastings, alms, and other works of piety and exercises of the Christian soldiery bring forth eternal rewards [only] for them. ‘No one, howsoever much almsgiving he has done, even if he sheds his blood for Christ, can be saved, unless he remains in the bosom and unity of the Catholic Church.’ 
If Feser sticks to universal salvation since suffering is universal, then his theodicy argument works, but it fails miserably if he takes the dogmas of his church seriously. Speaking of hell. According to Feser, nature wants us to bring many children into the world. That's why we should do it for moral reasons (natural law). But isn't it a little cruel to irrevocably expose one's own children to the possible danger of ending up in hell by procreating? One can do one's best in matters of (religious?) education, but the development of the children is not always in the hands of the parents alone. The children could fall away as adults from their faith (in the tyrannical Yahweh) and stand with one foot in the kingdom of the fallen light-bearer Lucifer. And this doesn't seem so unlikely if Feser is right with his description of modern society as ("largely")
stinking cesspool of wickedness and irrationality[,] (Feser)
which is supposed to go even further down morally ("Give the Humeans and contractarians time though."). According to Augustine, even a true Christian cannot be sure if he will come to heaven. In his opinion, the majority of Christians go to hell, not to mention non-Christians. So the probability of heaven/hell is not even 50-50 and even that would still be hard to bear. Masturbation and protected sexual intercourse (or other transgressions such as hedonistic drunkenness or everyday lies), which most baptized Catholics are certain to commit every now and then, actually lead directly to hell as deadly or mortal sins if they are not properly confessed and forgiven, or if the sinners do not receive absolution before they die. 

David Bentley Hart says something similar: 
If [some "Catholic philosopher" (Hart)] truly thought that our situation in this world were as horribly perilous as he claims, and that every mortal soul labored under the shadow of so dreadful a doom, and that the stakes were so high and the odds so poor for everyone—a mere three score and ten years to get it right if we are fortunate, and then an eternity of agony in which to rue the consequences if we get it wrong—he would never dare to bring a child into this world, let alone five children; nor would he be able to rest even for a moment, because he would be driven ceaselessly around the world in a desperate frenzy of evangelism, seeking to save as many souls from the eternal fire as possible. (David Bentley Hart - That All Shall Be Saved)
The churches may pretend in public that hell is empty, but secretly they think differently. Their speeches (especially here) are usually not Yes, yes! No, no! (Matthew 5:37). 

Eternal hell is (if there exists any afterlife or transcendent beyond at all) definitely a cynical and unprovable aspect of Christianity that transcends human standards of justice so that such an idea does not concern us. Besides, that idea cannot even be grasped by non-religious philosophical notions such as personal identity or time and space or timelessness and the like. Here is just one possible example: 
What has been created by another has had a beginning to its existence. Now that the same being, after having not existed at all for an infinite time, is supposed to continue existing through all eternity, is an exceedingly bold assumption. If at birth I first came to be and was created out of nothing, then it is highly probable that I will become nothing again in death. Infinite duration in the future and non-existence in the past do not go together. (Arthur Schopenhauer - Parerga and Paralipomena Short Philosophical Essays Volume 1)
Moreover, it is obvious that the idea of hell is also there to keep religious institutions stable. Reports about hell have always had a purely didactic purpose and an ethical function and that is how it will always be. One wants people to behave in certain ways, and for the average intelligent people, graphical descriptions of eternal torments are used as a means to convince them; for the intellectuals, rather very abstract descriptions are used for the same purpose. Sociologically, this was part of the civilizing processPsychohistorically, the idea of hell probably developed slowly and through small-step detours out of man's primal fear of death.

But from the point of view of historical Christianity one must be clear about one thing:
To put it succinctly: the founder of Christianity did not believe that the soul of a person who died would go to heaven or hell. (Ehrman, Bart D. - Heaven and Hell: A History of the Afterlife)
Toward the very end of the Old Testament period, some Jewish thinkers came to believe this future “resurrection” would apply not to the fortunes of the nation but to individuals. If God was just, surely he could not allow the suffering of the righteous to go unrequited. There would be a future day of judgment, when God would literally bring his people, each of them, back to life. This would be a resurrection of the dead: those who had sided with God would be returned to their bodies to live forevermore. Jesus of Nazareth inherited this view and forcefully proclaimed it. Those who did God’s will would be rewarded at the end, raised from the dead to live forever in a glorious kingdom here on earth. Those opposed to God would be punished by being annihilated out of existence. For Jesus this was to happen very soon. (Ehrman, Bart D. - Heaven and Hell: A History of the Afterlife) 
David Boonin holds the provocative thesis (especially for Feser it must be very provocative)
that it is morally impermissible for the state to punish people for breaking the law. (David Boonin - The Problem of Punishment)
Then, analogously, it can perhaps also be morally impermissible for God to punish people for offenses against moral laws.

Here is an interesting passage about the assertion that the Roman Catholic Church alone guarantees "salvation" and that, strangely enough, all people seeking salvation (but how should a non-Christian understand contrition and salvation?) belong to her (which completely abolishes the importance of baptism and confession)
At the end of This Is Catholicism (1959), John Walsh, S.J., reprints an important document which he introduces thus: “All the principal beliefs of Catholicism are summed up in the Profession of Faith which is made by converts on their entrance into the Catholic Church and by all candidates for the priesthood before ordination. It is a fitting conclusion for this book.” Here a great many beliefs are summarized succinctly in less than three pages. The final paragraph begins: “This true Catholic faith, outside of which no one can be saved. . . .” A few pages earlier, in the body of the book, we are also told that “membership in the Catholic Church, the mystical body of Christ, is the solitary means of salvation. Apart from the Church, exclusive of it, independently of it, there exists absolutely no possibility of attaining heaven.” This is the kind of forthright, unequivocal doctrine that at first glance seems to make it utterly unfair to claim that Catholic theologians, like Protestant theologians, disregard Jesus’ commandment, in the Sermon on the Mount, that we should let our Yes be Yes, and our No, No; “anything more than this comes from evil.” Immediately, however, Father Walsh asks: “Does this signify that all who are not actually members of the Catholic Church will be lost?” and in conformity with contemporary Catholic doctrine he replies: “Certainly not.” This is explained as follows: “When a person . . . makes an act of perfect contrition, he must simultaneously determine, as we saw, to accomplish everything which he judges necessary to attain salvation. Now since the Catholic Church is, in fact, the sole means of salvation, a non-Catholic’s resolve to do everything needful to gain heaven is, objectively considered, exactly equivalent to a resolve to belong to the Catholic Church. The two resolves automatically merge; one coincides with the other. A non- Catholic is unaware, certainly, of the identity of the two. . . . He may never have heard of the Catholic Church. Or he may . . . be quite indifferent to it. Or . . . he may be quite hostile to it and consequently would indignantly deny that his desire to please God coalesced in any way, shape, or fashion with a desire to join Catholicism. Such subjective misapprehensions on his part would not alter the objective fact, however. A sincere desire for salvation coincides necessarily with a desire to belong to the Catholic Church. . . . Strange as it may seem, therefore, a non- Catholic who sincerely yearns to do everything necessary for salvation (even when he believes that one of the requisites for salvation is to condemn Catholicism!) (John 16:2) is, all unconsciously, longing to be a Catholic. Now this unconscious longing God recognizes as a substitute for belonging . . . as the equivalent of real membership.” So the doctrine “still stands: outside the Catholic Church there is no salvation.” (Walter Kaufmann - The Faith of a Heretic)
There are established standard (classical) differences between final causes and efficient causes, i.e. between teleology and mechanism. And they go back to Aristotle. The interesting thing is that Feser completely ignores these differences in his argumentation for the existence of God. Here are the differences:
First, the final cause gives the idea of the whole, so that when we explain something according to a final cause we make the whole the explanans, the particular actions or parts the explanandum. In other words, teleological explanation is holistic. It assumes that the idea of the whole precedes its parts and makes them possible; we understand the part only by its place or function in the whole. Mechanical explanation is just the opposite: the parts are prior to the whole and make it possible. It supposes that the parts are self-sufficient units, each comprehensible on their own; and it forms the idea of the whole through the aggregation or composition of these parts. Hence mechanical explanation is not holistic but analytic or reductivistic [...]. Second, a final cause acts without being acted upon; it assumes [,for example,] that [an] organism is self-moving, self-regulating and selforganizing. An efficient cause, however, acts only if it is acted upon; it presupposes that there is some external cause for every event[.] (Frederick C. Beiser - Late German Idealism)
So let me now turn to the first proof of God from motion. This proof was not really convincing. What does it look like? I hold a stick in my hand with which I move a stone. This is a simultaneous causal series: hand, stick, and stone, all moving simultaneously and having an instrumental connection to each other (at least in one direction). Feser now believes that the series must end with an unmoved mover with the stone as the starting point of the series. Of course, the stone is actually the endpoint. But Feser's aim is to determine the first mover. So we have to go in a backward direction, so to speak. When it comes to determining what is given before or in front of the hand, Feser proceeds to the arm as the next causal member. But then he suddenly starts an inwardly going analysis. He gets to muscles, nerves, and finally to basic forces, atoms and other physical aspects:
That is to say, the hand’s potentiality for motion is actualized by the arm, and the arm’s potentiality for motion is actualized by the muscles, and the muscles’ potentiality for motion is actualized by the nerves; and again, all of this is simultaneous. But even this isn’t the end of the series. It continues on, through a number of simultaneous steps, to ever-deeper levels of reality. The motion of the stone depends on the motion of the hand, which depends on the motion of the stick, which depends on the firing of the neurons, which depends on the firing of other neurons, all of which depends on the state of the nervous system, which depends on its current molecular structure, which depends on the atomic basis of that molecular structure, which depends on electromagnetism, gravitation, the weak and strong forces, and so on an so forth, all simultaneously, all here and now. (Edward Feser)
Why does he do this? The inward-going analysis still remains in the arm, I can zoom in as deep as I want, it does not lead me out of it. Either I go through the individual parts of the arm, or I leave it completely in order to really expand the causal series. A third possibility is excluded. Moreover, it is surprising why Feser suddenly uses the language of mechanical physics, which actually contradicts his Aristotelian philosophy. Thereby the Aristotelian efficient cause is no longer clearly distinguished from the Aristotelian material cause. Feser gives the impression that the atoms of the arm assume the role of an efficient cause and then collectively cause the arm as something supposedly different and separate in an efficient-causal way, although these atoms belong to this specific arm only as a material cause, i.e. to its form of identity:
For notice that, especially [why especially?toward the “lower” levels of the series [still an essentially ordered, efficient, simultaneous, and hierarchical causal series] we were considering – the nervous system’s being actualized [but also the muscle system, cell system and so on] by its molecular structure, which is in turn actualized by its atomic structure [materialistically speaking, the nervous system is identical(!) with a certain atomic structure. Nothing needs to be actualized additionally], etc. – what we have is the potential existence of one level [so also the level of the whole exterior arm] actualized by the existence of another, which is in turn actualized by another, and so forth. To account for the actualization of the potential motion of the stone we had eventually to appeal [why?] to the actualization of the potential existence of various deeper levels of reality [transition from motion to existence? Something gets conceptually very confused here!](Edward Feser)
Feser also suddenly changes the vocabulary when he says that something depends on something else. With this expression "depends on" he hides his mechanistic way of thinking (Feser should also first and foremost define the concept of dependence clearly and unambiguously, but this does not happen). Before introducing the new word, he makes it clear that it is still about the same causal series where each member causes resp. (spatially) moves the next one as an efficient cause
But even this isn’t the end of the series. It continues on, through a number of simultaneous steps, to ever-deeper levels of reality. (Edward Feser) 
Feser ties not very convincingly the series of simultaneous moving causes to a series of necessary or sufficient conditions (external or internal) of existence (survival in the case of an organism). However, the latter series is a very different series that requires its own analysis. 

To repeat it clearly once again. Feser links two different types of movement together in one and the same causal series.

Aristotle famously distinguishes four types of motion: quantitative motion (growth, shrinkage), qualitative motion (change of form), spatial motion (change of place), and ontological motion (coming into being, passing away). To put it another way: Change, according to Aristotle, can occur in four different ways (Phys. III 1, 201a3- 9): as a change in quantity (e.g., when something becomes smaller or larger), as a change in quality (e.g., when something bright becomes dark), as a change in substance (when something comes into being or passes away), and as a change in place (when something moves or is moved from one place to another).

Feser now ties the spatial movement to the ontological movement, the change according to place to the change according to substance, without justifying this step more precisely. As a reminder, Feser started with the local motions of stone, stick, arm, muscles, but ended with the mere existence of neurons, molecules, atoms, etc.

However, this contradicts Aristotle's first theorem about change: Every change takes place between opposites (quantitative: e.g., small-large; qualitative: e.g., immature-mature; change according to substance: e.g., non-house and house; change of place: e.g., up-down).

Feser wants to make us believe that in order to explain motion, one must at the same time explain the existence of what is in motion. But this is anything but self-evident. In fact, it is counterintuitive. Aside from the fact that Aquinas' original proof focuses only on movement in a series of movements, existence is nevertheless always implicitly or explicitly thought of. Existence is always taken for granted and presupposed. If there is a change of state from cold to hot, then it is clear that at or in a thing the states change. Only one does not come so to a God, but only to another thing which already exists in the state of hotness and heat.

Here are three more critical points:
  • Besides, my arm is identical with a certain muscle, cell, nerve, blood and bone structure or with a certain molecular structure or an atomic one. There is always an identity relationship and not a causal one because the arm is just a name, so instead, you could use a description of a certain structure of organic or atomic material as a lengthy name for what is called the arm
  • How does Feser know that everything that is caused is caused by another? Does this follow from the definition of causing or does he know this from experience? If he has established it definitionally, nothing follows from it for reality, but it would be only a rule of thought, not a law of being. If he claims to know it from experience, then the question is, how many experiences does someone have to have in order to know that everything is caused by another? No experience results in the universal character of his statement, that par excellence every change has a cause.
  • When the material parts in my body and the material stuff in its surroundings completely produce me and my mind then we get a very unchristian human image. If they don't completely cause me, something remains that doesn't (to borrow Feser's expression) depend on those parts.
According to modern physicists, Aristotle's terminology has no validity in Feser's "ever-deeper levels of reality":
At the deepest level we currently know about, the basic notions are things like “spacetime,” “quantum fields,” “equations of motion,” and “interactions.” No causes, whether material, formal, efficient, or final. (Carroll, Sean - The big picture)

Conventional causality is no longer present in the quantum domain (the deepest level of reality)

Regarding the supposedly deeper levels: arm, nervous system, cells, molecules, atoms, quarks, forces, quantum fields and whatever. I say "supposedly" because Feser basically never goes into a deeper level. For he always stays on the level of physical or spatial extension. One can imagine it in such a way that the human being is represented by a geometrical line which has a starting point and an end point, and that Feser's moving forward means nothing else than that the line is divided more and more into sectors by intersections. When Feser arrives at the quantum fields, it only means that said line has extremely many intersections and therefore extremely many short sectors.

Feser simply does not believe, although in principle nothing speaks against it, in a "line" that exists in and of itself.

The true step into the deep would be the one into the mental (mentality), into the psychic inner world of the human being. There, things do not happen spatially but exclusively temporally.

The mental would thus be the cause of the movement of the hand in Feser's example. But Feser probably wanted to avoid this in order not to get into even bigger philosophical problems (What causes the mental or is it something that is spontaneously self-caused?).

In the context of a pantheism there would be still another and last step inward. This is then called unio mystica: The unio mystica or Henosis, the becoming one with God, often also called Mystical Marriage by the medieval female mystics, is the highest aspiration of the mystics. The Neoplatonist Plotinus experienced this unio mystica several times in his life, as his disciple Porphyrios reports in his biography of the admired teacher. He emphasized the All-is-One/God/Nature and was thus a direct predecessor of the pantheists. In the third and last step, one finally left the temporal.  

I can also save myself the search for another link in the causal series and go directly to God. Whether there are still one or two things in between (i.e. between my arm and the unmoved mover) does not change the conception of the supposed proof of God. But if I now fall back on God, he is also the one who moves my arm, which would inevitably degrade me to a pure puppet 
because it is only the first member which is in the strictest sense really doing or actualizing anything. The later members are mere instruments, with no independent, actualizing power of their own. (Edward Feser) 
In his paper "Infinite Causal Regression" Patterson Brown expresses himself much more cautiously and criticizes the principle of a per se ordered causal series 
as involving a too legalistic notion of causality which comes close to equating it with responsibility[:] 
"It is clear that everything that is moved is moved by the movent that is further back in the series as well as by that which immediately moves it; in fact the earlier movent is that which more strictly moves it." [Aristotle] This seems to be a way of saying that an unmoved mover has some sort of causal responsibility in a way that a moved mover has not. Consider the following case. Mr. Alpha is in his automobile, stopped at an intersection. Immediately behind him sits Mr. Beta in his own car. Behind Mr. Beta is Mr. Gamma, behind whom is Mr. Delta, and so on indefinitely. Suddenly Alpha's car is rammed from the rear, damaging his bumper. So Alpha, desiring to recover the expense of repairing his automobile, accuses Beta of having caused the accident, and brings suit against him. Beta, however, successfully defends himself in court on the grounds that he had himself been rammed into Alpha by Gamma. So Alpha now sues Gamma. But the latter, it turns out, had in turn been rammed by Delta. So Alpha takes legal action against Delta. And so on indefinitely. Now, if this series of rammings extended ad infinitum, there would be no one whom Alpha could successfully sue as having caused the dent in his bumper; there would, in short, have been no cause for the accident at all. But if there were no cause, no mover, then there would be no effect, no moved, either-which is patently false, since Alpha's bumper is dented and his car was moved. Therefore there cannot be a regress to infinity of ramming automobiles, but rather someone was the first cause of the whole series of accidents; someone can properly be said to have moved Beta into Alpha, Gamma into Beta, Delta into Gamma, and so on. Therefore there is someone from whom Mr. Alpha can collect his expenses. In this rather queer argument the legalistic sense of "cause" is manifest; the cause of the damage to Alpha's car will lie wherever legal responsibility lies, in this sense of "cause." It seems to me to be an allied (though not identical) notion of causation which is being employed in the Aristotelian argument against infinite regresses in all per se ordered causal series. (Patterson Brown - Infinite Causal Regression. In: Aquinas – A Collection of Critical Essays edited 1969 by Anthony Kenny)
Patterson Brown mentions why the series of simultaneous causes cannot be infinite. Feser, on the other hand, doesn't really make this point clear but rather beats around the bush. The reason is that the simultaneous causal series represents an action, a self-contained (closed), somewhat anthropomorphic, and single action, which, if its components were infinite by number, would never come to an end. Moreover, it would also never get off the ground. There would be no identifiable and imputable action in the first place. Nevertheless, we must not ignore the fact that following this Thomist understanding of causation we would be poor marionettes.

This might then be a consequence:
Belief in free will seems to be a necessary illusion given by God to protect the fragile human ego from the shock of seeing the reality of God’s dominance[.] (Tagliaferre, Lewis - Theofatalism: Theology for Agnostics and Atheists)
It is questionable whether the per se ordered causal chains exist at all in the world (think only of the relativistic effects)
Finally, in explaining the meaning of a hierarchical series of causes, James Ross has suggested the following:
... in a stack of bricks the one which holds up the top one exercises its causality in holding the top one where it is only by virtue of the fact that the bricks under it are holding it up, and so on down through the whole stack. Such an ordering of causality is an essential ordering.
This illustration is more successful than the previous attempts. Here we do have a structure of causal relationships in which each cause (i.e., each brick) depends on the existence of a previous cause (i.e., a lower brick). Unless there were a first brick, a foundation for the series, the stack would collapse.

While this example clarifies the notion of hierarchical causality, it has no applicability to the natural universe. If the universe consisted of solid chunks of matter, each resting against the next, then this analogy might serve some purpose. Perhaps we could infer a basic brick of the universe, and perhaps we would choose to call this brick “god.” In the context of the present universe, however, the above illustration is useless. Antony Flew correctly notes that the hierarchical first-cause argument retains its superficial persuasiveness only as long as we “continue to think in the familiar terms of temporally successive links in causal chains. ...” After we remove the concept of causality from this context, we cannot assume that there is an “order” of causes in the universe. The theist must demonstrate, not assume, that such an order exists. Before he can accomplish this, however, he must explain what he means by hierarchical causality. If we are told that Atlas supports the world on his shoulders and thereby “sustains” it, we at least get a rough idea of what is meant by “sustains.” But when the theist tells us that god sustains the universe, or when he tells us that god is the first cause of a mysterious hierarchy, we are not presented with an intelligible explanation of the subject being discussed.
(George H. Smith - Atheism. The Case Against God)
Back to the proof of God. On the other hand, I could say that my intention, which represents me as a whole human being, has moved my arm and thus the stick and the stone. So I don't have to go back to God anymore. The causal series ends with my intention, which has emerged spontaneously from my active will and has no essential cause, but an accidental reason or ground for action. Feser's argument merely showed that although there must be a primary mover, it only needs to be active in that respect which is relevant to the given case of movement. Nothing more. There is no reason to point to God who, according to Feser, is active and actual in every possible respect. This results in many worldly first movers (uniform, non-reducible, active, and, in a certain respect, actual forms), such as man (i.e. his specific human form or the form of humanity or mankind). Even Aristotle saw it this way, and Feser could easily have gone from the arm to the whole human being in the same way (the transition from hand to arm was already made by Feser). For Aristotle says: 
e.g. the stick moves the stone and is moved by the hand, which again is moved by the man: in the man, however, we have reached a mover that is not so in virtue of being moved by something else. (Physics 256a-256b+) 
The Catholic theologian and philosopher Scott Macdonald comes to the same conclusion:
Assuming that Aquinas can block a regress in the case of movers and things moved, why must the primary mover be not just unmoved, but unmovable? Aquinas thinks that if the mover of some moved thing is not itself moved, it is an unmovable mover [...]. What justification does he have for supposing that an unmoved mover is unmovable? The sort of causal series he has in mind in the proof from motion has as a member something, M, that is being moved. M’s going from being in potentiality with respect to some state S to being in actuality with respect to S needs to be explained by some primary mover, P. All that is required of P is that it be in actuality with respect to S; P’s being in actuality with respect to S is what makes P the primary mover in this causal series ordered per se. So in order to count as a primary mover, as the stopping point in a causal series ordered per se, P must be unmoved (because it is in actuality) in the relevant respect. But it does not follow from this that P must be unmoved (and hence in actuality) in all respects. If P were in actuality in all respects, P would be absolutely unmoved and unmovable, but the fact that P is unmoved with respect to some state S does not entail that P is unmovable. Given that Aquinas’s argument so far has shown only that there must be some primary mover that is in actuality in the respect relevant to the particular case of motion at hand, it seems likely that there will be very many relatively uninteresting primary movers. The fire in our paradigm case seems to be a suitable primary mover, animals (or their souls) might be unmoved movers, and some of Aquinas’s own examples of causal series ordered per se apparently have human beings filling the role of primary mover, at least as Aquinas describes them. We might call fire, animals, human beings, and other natural unmoved movers (if there are any) mundane primary movers. The problem, then, is that the proof from motion gives us no reason to suppose there are any primary movers other than mundane primary movers. (Scott Macdonald - Aquinas’s Parasitic Cosmological Argument)

The mundane prime movers could be attached to an accidental causal series that is non-simultaneous:

An alternative strategy is to argue that every essentially ordered causal series has a first member, where a causal series is essentially ordered if no effects within the series can exist without their causes also existing (e.g., the movement of a stone depending upon the pressure of a stick). The thought is that even if some causal series can be infinite, no essentially ordered can be. A proponent of this strategy faces the challenge of explaining why a first cause in an essentially ordered series could not have been caused by things within a non-essentially ordered causal series. (Joshua Rasmussen - Cosmological Arguments from Contingency)

Feser's proof would only say: There are essential first causes. But they themselves could be caused accidentally. They could result from accidentally ordered series (non-hierarchical, non-simultaneous).

Aristotle himself gives an example for an accidentally ordered causal series:

As, when something has caused motion in water or air, this moves another and, though the cause has ceased to operate, such motion propagates itself to a certain point, though there the prime mover is not present[.] [464a1] [5]" (ARISTOTLE - ON DIVINATION IN SLEEP)
And those essential first causes would not have to be completely in actuality:

For even if something cannot be actually and potentially F at the same time, this does not show (and it cannot be shown) that something cannot be actually F and potentially G at the same time; for example, a person can be actually musical but potentially athletic. (RICHARD GEENEN AND ROGER HUNT - The Prime Mover Removed: A Contemporary Critique of Aquinas' Prime Mover Argument)

So it is understandable, why Feser does the (strange) inward analysis by example of the arm. He simply wants to escape the clear and evident objections by Scott McDonald. Thus Feser starts, out of the blue, from two additional assumptions, one of which is unproven and the other highly problematic because it contradicts popular Aristotelian notions. 

The first assumption is the principle that things can theoretically be divided infinitely, which Feser should first prove before he implements it into his considerations. For if things were not infinitely divisible, one would then come to the last monadic entities (for example, forces, powers, point-particles, or quarks), which, in a certain respect, could be self-moving and active and independently actual. Feser just does not want that. I am not saying that he truly believes in the infinite divisibility of natural entities. He would only use it as a kind of tool of argumentation. For example, an opponent could tirelessly advance in the causal series, with Feser always nodding, somehow agreeing, but also stating that we need a beginning to stop a vicious regress. If the opponent wanted to stop somewhere and claim that we have now reached a point where a division can no longer take place (because we have arrived at indivisible worldly things), Feser would raise an objection using the divisibility principle and say: the alleged indivisible components would again have parts, so that they were formed into wholes by these new parts in an equally essential and efficient causal way. Such would go on until finally an immovable transcendent God is forced. But to 
[j]ump from a first immanent cause to a first transcendent cause appears [it doesn't only appear so] to be one of the most questionable moves in the Thomistic program. (Edward N. Martin – Infinite Causal Regress and the Secunda Via in the Thought of Thomas Aquinas)
Yet even more baffling, Feser 
offers us the explanation that God is the first transcendent cause, which, given God’s eternality and immutability, is prima facie [but not only prima facie] very hard to accept. (Edward N. Martin) 
His train of thought here also somehow suggests that he supports a kind of atomism of a somewhat Thomist type, which he otherwise keeps secret in other places. If God stops the regress, then we probably have as the second member of the series - after God of course, who is the first member - a physically indivisible entity. But do the Thomists really want to accept such an entity (it would be the first non-transcendent member of the series)? For we would have then a hard-boiled reductionism, because everything worldly would depend in every respect on these immanent first entities, i.e. would be reducible to them. They would actualize for example the electrons, neutrons and quarks, these would actualize the atoms, the atoms would actualize the molecules and so on. Fox ITK has some great thoughts on this topic: 
As I see it, we have two options: Option 1: either a regress of composition terminates in some simple part of a composite which is not further composed or: Option 2: the regress does not terminate in some simple part, but a simple thing extrinsic to the composite which must at some level of the composition act to terminate the regress of composition. This assumes of course that the regress is not possibly benign, and so must terminate in some simple thing one way or another The dilemma consists in (1) not being an option for the Thomist. It amounts to accepting the existence of simples that they rule out for various reasons. So we all know it’s going to be the 2nd horn they take. But, the problem I have, is that if it's (2) then as we lack some fundamental level of composition, we have no level of the series that a simple external cause can act on such that it will account for the totality of composition that would be required to vanquish the regress worry.
Take some arbitrary level of composition, called n - looking at n it obviously has parts as n can not be simple for the Thomist, and so these parts of n will themselves have parts, and so on infinitum- at which case, we have to ask what terminates that regress of n parts even if the regress of composition after n > is terminated in the simple external cause? Sure, the regress for all composition subsequent to n may well have been terminated, but this cuts out at n level of composition, such that for every composition prior to n it is not accounted for by the simple external cause acting on n , and thus we are in need of something to stop the remaining regress. But any step would simply introduce a fresh regress worry given we will always be dealing with what is already a composition when appealing to an extrinsic simple cause. Because it doesn’t seem as if that external simple thing being invoked at n is grounding the n parts, which are prior to n and are what it strikes me, are really grounding it. The worry for what grounds n does not appear at this local level, thus invoking an external ground for n seems unwarranted. Even if there’s a worry about what ultimately terminates this regress, it’s still the case that n is grounded by its parts, so it seems that involving the external simple thing to terminate the regress worry at n is unneeded.
More generally, my worry is this- a hierarchical series is transitive in its dependency relations. The worry is that without terminating in something simple, then being is infinitely deferred and never achieved. But if there is no first part of the composition that can be said to be acted on such that this act is totally transitive throughout the entire series of composites (that is there’s no subvening composition left to be accounted for- the only way is up) then an extrinsic cause could not act on some non composite member such that it in grounding that member it subsequently grounds the entirety of the series via transitivity. It strikes me that we would need a first member to be able to achieve this sort of transitive relation (some first member that was in need of such an act) yet by definition, such a first member would be non composite and so not in need of such an act to explain a composition it does not have. This is akin to taking option (1). Regardless, the Thomist is actually committed to ruling out such first members (simples that aren’t further composed) but even if on reflection they did, in doing so they undermine the argument. So either the regress terminates in some simple part, or it continues. I don’t really understand how the simple external cause stops it. I get that simplicity stops the regress of composition in one’s explanatory chain, but that simple is not a simple of a composite as a part, which is what we are trying to halt, not merely a regress of explanation, but a regress of composition. If the Thomist’s solution fails then either simple a or gunk are left to offer a solution- either of which show the arguments based on composition to be false.
the point that seems clear to me, is that there's a problem brought on by the rejection of some simple that itself halts the regress- the implication is that the regress would continue. So they invoke God as a regress stopping simple. But if God directly prior to the series of mere instrumentally dependent members in the series- he must act on the first of these for that act to be totally transitive. But any first member would, in the case of a composite, be a first member with no further parts. In which case, it can't be a first member at all.

that's because if the first member lacks parts, it is a simple and the regress would already have halted.

Feser's argument seems to both need simples (in order for God's act to be transitive on some member to transmit this act throughout the series) and for it to be impossible for there to be simples (because if there was the regress that motivates the invocation of God as a simple would be halted, and the cause would be redundant).

An interesting way to think of it- say you want God to act in one way such that he sustains everything. How is this achieved? I assume it's by acting on the fundamentalia, quarks/strings/field foam which uphold the rest of the world. God's act is thus transitive from some fundamentalia to everything in creation. But say that things liek quarks/fields are not fundamental. Then in acting on them, God is holding up by transitivity of his act to all the observable universe we understand, but not everything because the quarks/forces are being actualised by whatever composes them, and so we have a failure of the sustaining cause to sustain everything. Worse still, it feels as if the cause on the quarks/fields etc is redundant, totally unneeded- the real source of the transitivity of dependency is found prior to the quarks/fields etc for everything we observe.

But if the quarks/fields really were fundamental, then we have no regress of dependence on further parts, and so no need to invoke the divine cause to sustain the composition we see. So is God redundant in the former or latter sense? Either way Feser's solution doesn't work.  

Here you can find more from Fox ITK on this important topic:

On the other hand, with all that has been said, one can also ask oneself the following questions:
Why shouldn't the series of causes go on into infinity? How does [Aquinas] know that? Perhaps it does go into infinity after all? Thomas justifies this regulation with the fact that otherwise there would be no primary cause. But this is supposed to be the result of the argument. He already uses it within the course of argument and proof. (Flasch, Kurt - Warum ich kein Christ bin: Bericht und Argumentation. Why I'm not a Christian: Report and argumentation)
The causal series could theoretically be a potential infinity. This is quite clear when the cause precedes its effect or at least begins earlier. For Feser cause and effect are simultaneous. The idea of infinity would then not be completely self-evident here, but at first glance, it wouldn't be absurd either because of the possibility of mereological gunk and, if you change the vocabulary a little and say that parts form wholes logically rather than creating or causing them efficiently. Since God is not an empirical object, and the series of parthood might be potentially infinite, we have allowed enough room for doubting the existence of God. I will come back to the concept of simultaneous causality later.

Fox ITK sees it similarly:
Again, I don't think it is- a potential counterexample to an essentailly ordered series that lacks a first member (according to some!) would be metaphysical gunk- which is a series of parts and wholes that for each part of some level of composition, that part itself has proper parts, and so on infinitum. Again, one gives up a metaphysical foundation or bottoming out when considering gunk as possible, and it seems conceivable to experts in the literature.
Feser also owes us the proof of why there can be no actual infinity. Without this proof, all his further remarks belong in the category begging the question. The proof must take place without reference to the opposite position. Only an internal logical violation must be demonstrated. 

William Lane Craig also has something to contribute:
The principal argument used to eliminate such a regress is that in essentially ordered infinite regress of causes, only instrumental causes would exist, and, hence there would be no intrinsic causality in the series to produce the observed effect. The defender of this argument faces, however, this dilemma: if an instrumental cause is defined as a cause lacking intrinsic causal efficacy, one cannot preclude an infinite regress of instrumental causes each receiving its causal efficacy extrinsically from its predecessor but if an instrumental cause is defined as a cause depending ultimately upon a first cause, then it cannot be shown that the causes in an infinite regress are truly instrumental. (William Lane Craig - The Cosmological Argument from Plato to Leibniz)
The concept of causality is originally a purely world-immanent concept (causality between an empirical thing and another empirical thing), and its application to something transcendent (outside of time and space) seems both extremely demanding and strenuous, if not abusive, to that concept. If the theologian takes this semi-transcendent step (causality between an empirical thing and a transcendent thing), then the atheist is not wrong when he applies the causal concept completely to the transcendent (causality between a transcendent thing and another transcendent thing) and asks where God now comes from. Even if the Thomistic God can only be thought of as simple, he would still have to possess an infinite fullness and a never-ending richness, perhaps brought forth by an even more incomprehensible being. Metaphysical speculations simply have no limits. 

All in all, there is also the serious suspicion that Feser's causal principle already starts from a god and does not show neutrality in this respect. It seems to be something transcendent and therefore mystical, magical, and fabulous. 

Feser's reconstruction of the Thomistic cosmological proof is nothing new. For already before him one tried to save this proof by interpreting it completely in terms of the argument of composition. But such an interpretation leads only to a circular proof, as the presumably Catholic philosopher Antoine Côte admits:

In an attempt to vindicate the celebrated "Five Ways," John Lamont tries to show that Aquinas's arguments for an uncaused cause are successful provided they are understood as resting on an argument from composition.' Lamont further seeks to show that an uncaused cause must be immaterial and unique. In this paper, however, I shall argue that even if we accept the translation of Thomas's various proofs into an argument from composition, such an argument need in no way be thought of as implying the existence of an uncaused cause. Further, I shall show that Lamont's argument for the immateriality of the uncaused cause is problematic and his argument for its uniqueness unconvincing. [...] To sum up: Lamont, following Peter Geach, tries to show that Aquinas's proofs for the existence of God can be construed as a valid composition argument. I have argued that insofar as we can reduce the Five Ways to a composition argument, such an argument in no way yields the desired conclusion. The failure of Lamont's attempt is explained by the fact that he makes the proof of God's existence into a deductively valid composition argument only by begging the question with respect to the fundamental issue, namely, that the sum of all effects is really a group in need of a singular cause different from the causes of any of the effects of which it is the aggregate. Finally, inspection of Lamont's reasons for arguing in favor of God's immateriality and uniqueness reveals that such attributes could be seen to be validly predicated of God only by excluding alternative hypotheses which Lamont does not even envisage. (ANTOINE COTE - THE FIVE WAYS AND THE ARGUMENT FROM COMPOSITION: A REPLY TO JOHN LAMONT)

One could create a sort of Thomist theory about existing simples regarding string theory, which is the latest physical explanation of the foundations of the world. Brian Greene gives an illustration of string theory:

One-dimensional strings could be pure actualities that produce quarks that contain potentiality (just as the Thomistic God as pure actuality must also produce potentiality in the world). Furthermore, a particular vibration pattern (the pattern may probably only be understood in an analogous sense and only expresses that a string cannot be an absolutely simple simplicity from which nothing really complex and new can originate) could hardly be understood as a composite part of an energetic string filament. One can certainly not say that a string is composed of a string itself as a substance and of a particular vibration pattern as a separable property. I would vehemently oppose that. Then one can say that the strings as unmoved movers would be devoid of passive potency (the ability to be affected by other things like other strings or quarks and so on) but would have full active potency (the ability to cause effects in other things like all quarks). By the way, the latter Thomistic expression is for me an oxymoron, a wooden iron. Although the individual strings cannot influence each other's internal activity, they may influence each other externally, in the sense that they could possibly hinder or reinforce one another in their influence on the potentials of composites (in a way incomprehensible to our intellect). Or they do not influence each other externally and exist only in parallel. If the vibration pattern should change, then this happens only "from within" the respective string itself, not by anything else from the outside. But I'd rather rule out a change in the pattern. And it must be stressed that the individual string just is in motion, without being moved by anything, whether by itself or by anything else. 

One might argue that the strings have extrinsic potentials with respect to the constellation they can have to each other. But no string has this potential, they don't "know" anything about each other, the potential lies only with any hypothetical or theoretical external observer, who has the potential to "see" another constellation of strings.  

It is also of importance to note that a string would be nothing remotely like a mind or divine being: it lacks cognition or consciousness, cannot set itself goals or seek ends that are conceived as good. Also, the string itself can in no way be described as good, nor as evil. It merely has the neutral non-teleological (in every respect blind and without final purpose) tendency to produce quarks, possibly forever as a matter of sheer brute fact. Consciousness and cognition, on the other hand, would be very late-stage, secondary, and probably only emergent phenomena. Or one assumes a kind of naturalistic panpsychism, which assigns a simple conscious interiority or inwardness to the single string or its first product, the single quark so that explaining complex human consciousness becomes much less problematic. 

I know that Thomists would regard concepts such as tendency like conservation of momentum (constant motion which is natural and expected) or such as final or end state like ultimate heat death to be necessarily teleological concepts, but I don't think one is forced to interpret them that way. They can be understood completely free of teleological meaning. 

A string could perhaps be interpreted as an individual simple to which one could not apply the concept of substance. Bertrand Russel points to a problem of that concept:
‘Substance’, when taken seriously, is a concept impossible to free from difficulties. A substance is supposed to be the subject of properties, and to be something distinct from all its properties. But when we take away the properties, and try to imagine the substance by itself, we find that there is nothing left. […] Substance’, in fact is merely a convenient way of collecting events into bundles. What can we know about Mr Smith? When we look at him, we see a pattern of colours; when we listen to him talking, we hear a series of sounds. We believe that, like us, he has thoughts and feelings. But what is Mr Smith apart from all these occurrences? A mere imaginary hook, from which the occurrences are supposed to hang. They have in fact no need of a hook, any more than the earth needs an elephant to rest upon. Any one can see, in the analogous case of a geographical region, that such a word as ‘France’ (say) is only a linguistic convenience, and that there is not a thing called ‘France’ over and above its various parts. The same holds of ‘Mr Smith’; it is a collective name for a number of occurrences. If we take it as anything more, it denotes something completely unknowable, and therefore not needed for the expression of what we know. ‘Substance’, in a word, is a metaphysical mistake, due to transference to the world-structure of the structure of sentences composed of a subject and a predicate. (Russell, Bertrand - History of Western Philosophy)
Galen Strawson sees it the same way Russell does: 
[T]here is no real distinction, only a conceptual distinction, between a concrete object, considered at any given time, and its concrete propertiedness at that time (no real distinction, in another vocabulary, between a substance at a time and its essential attributes at that time, whatever modes of those attributes are instantiated at that time)[.]


This thesis is indeed radical and initially difficult to think, given the structure of human thought and language, given in particular that ‘property’ is an intrinsically relational word that demands something for a property to be a property of, but it’s sufficiently understandable for all that, and fully in line with the intuitive metaphysics of present-day physics. Does it seem hard to think? Yes, but it’s not that hard, and it’s something one can cultivate and grow into—deeply. This is doing philosophy. 
I don’t think Ramsey exaggerates when he says that ‘the whole theory of universals is due to mistaking . . . a characteristic of language . . . for a fundamental characteristic of reality’ (1925: 60). And Whitehead only exaggerates a little, perhaps, when he says that ‘all modern philosophy hinges round the difficulty of describing the world in terms of subject and predicate, substance and quality, particular and universal’ (1927–8: 49). Both agree with Nietzsche that 
language is built in terms of the most naïve prejudices . . . we read disharmonies and problems into things because we think only in the form of language—thus believing in the ‘eternal truth’ of ‘reason’ (e.g., subject, predicate, etc.). (Galen Strawson - Nietzsche’s Metaphysics? In: Nietzsche on Mind and Nature edited by Manuel Dries and P. J. E. Kail)
In my interpretation, strings would be true simples. There would be no further substructure. The question of their composition would have no meaning and would be without any content. Feser says that 
God is not something we should expect to be able fully to grasp, given the limitations on our intellects.
The same should rightfully be true with regard to strings. We could never fully grasp them, "given the limitations on our intellects". At least we can grasp them mathematically, but this does not mean much for a deep metaphysical understanding. 

If the simple strings all had the same vibration pattern, Feser would ask how they could be distinguished from each other. A discussion between Edward Feser and the atheist Graham Oppy on youtube dealt with this topic. In a comment to the video I found a clever remark by Fox ITK (I will quote the whole comment in the appendix below):
The point Ed presses about the principle of individuation seems to me very weak. ‘what distinguishes one simple from another?’ doesn’t that by which they are distinguished lead to composition? I don’t see why things like Cambridge properties, or spatial or temporal properties are like ‘parts’. Ed would accept that God has so called Cambridge properties, but being simple they aren’t parts, they are relations etc which are extrinsic. Why aren’t these enough to distinguish simples? As far as I see they would. Ed’s response was to go beyond composition at this point to ask ‘what caused these different extrinsic properties? And that’s a different argument entirely, and if this is where we get to then we have moved beyond the scope of the argument to support it, and so I’d deem the argument a failure (after all, Oppy could just appeal to say past events explain why the spatial properties are such and such (of which this would be an accidental cause, which need not persist as an essential cause would).
Kant gives a good example of mere extrinsic distinctiveness:
Take two drops of water, and set aside any intrinsic differences (of quality and quantity) between them; the mere fact that they have been intuited simultaneously in different locations justifies us in holding that they are numerically different, i.e. that they really are two drops. (Immanuel Kant - Critique of Pure Reason up to the end of the Analytic)
My (probably analogical) illustration with necessarily existing strings may not be perfect (in places faulty)but it should make it clear that a plurality of immanent simples (priority pluralism) isn't logically impossible. Quite the contrary, it is more consistent with our empirical experience of a pluralistic world, even if such a plurality of immanent simples is only possible outside a Thomistic framework. 

How to conceive of simples in yet another way:
Since space, according to Leibniz, represents only the outer phenomenal structure of the monads, a distinction has to be made between the inner indivisible energy core of the monads and the outer appearance, which then also allows the infinite mathematical divisibility in space. The space is the area of the outer presence of the monad - "who therefore divides the space, divides only the extended size of its [the monad's] presence" (I, 481). The subject of the monad cannot be divided by this. The spatiality of the substances in the phenomenal realm is contrasted with an inner, non-extended and therefore indivisible intelligibility of the monads. The metaphysical concept of substance is thus preserved. The substance is to be thought in analogiam Dei. (Translated with; Irrlitz, Gerd. Kant Handbuch [Kant Handbook])
Or one describes the simples like Schopenhauer, but only more benevolently: 
An atom allegedly could not be merely a piece of matter without any pores, but instead, because it must be indivisible, it would either have to be without extension (but then it would not be matter) or endowed with absolute cohesion of its parts, i.e., one superior to every possible force. (ARTHUR SCHOPENHAUER - Parerga and Paralipomena)
The parts of which Schopenhauer speaks at the end exist in fact only in our imagination

In the history of philosophy, the plurality of (fundamental) simples that constitute the world has always been discussed (Aristotle, for example, inferred the existence of over forty unmoved movers):
Plato's arguments for the existence of the gods and for what he takes to be their nature have the virtue of simplicity. His "proof" of the existence of the gods is an argument from motion. There are, as he sees it, ten kinds of motion: motion on an axis, locomotion, a combination of these, separation, composition, growth, decay, destruction, external motion, and spontaneous motion. The last of these, "the motion which is able to move itself, is ten thousand times superior to all the others." More important, it must have come first and be "the origin of all motions." Next, "the motion which can move itself' is identified with the soul. If both of these steps are accepted, we have indeed "the proof that the soul is the first origin and moving power of all that is."Plato specifically rules out the possibility that the first origin of all there is could be traced back to a single soul: "we must not suppose that there are less than two—one the author of good, and the other of evil." Neither here nor elsewhere, however, does Plato suggest that in fact there are only two such souls: what he insists on is that there could not be only one because in that case evil could not be accounted for. Plato proceeds apace to say that the soul of the sun "ought by every man to be deemed a god"; and he adds: "And of the stars, too, and of the moon, and ... all things are full of gods." With that, he feels that he has "said enough ... to those who deny that there are gods." If we analyze this argument, we are immediately faced with a hidden premise; namely, that rest alone is natural while motion is in some sense unnatural and must be traced back, as it were, to some disturbance, to some force which started it. Many writers, including some of the best, feel that it is unfair to question any such presuppositions, and that the historian should make them explicit only to enable us to feel our way back into the spirit of the age. This, we are told, is how men used to think; in those days they could not think otherwise. But in the case at hand, and in the case of all the proofs God's existence, this claim is manifestly false. Plato's older contemporary Democritus, who was perhaps the greatest thinker of his time, next to Socrates and Plato, although Plato never deigns to mention him, had been quite able to dispense with Plato's premise in this instance and in fact had denied it explicitly. He had held that all things consist of atoms, and that these atoms are naturally in motion and have always been in motion. He had expressly denied the need for any separate principle of motion and had thus differed from his predecessors who had introduced a number of such principles. He was a younger contemporary of Socrates, and his philosophy must have been known to Plato and his audience. Even if we grant Plato the hidden premise which he needs, his argument is not compelling. He leaps to the conclusion that what moves itself must be a soul, and from the soul to god. His introduction of the soul is highly questionable, and his claim that all these souls are gods lacks even plausibility—unless you happen to believe in gods before the argument begins. The introduction of the word "gods" is crucial not only because the existence of the gods was the thing to be demonstrated by this proof but also because it is this term that leads Plato to say immediately—although this neither has been proved nor is even consistent with what he himself has said a few lines back—that the gods are, of course, "perfectly good" and "hear and see and know all things" and hence must care about men's actions and, moreover, being just, cannot allow themselves to be bribed by either sacrifice or prayer. And thus all of Plato's dogmas have been "proved." Even if all motion could be traced back to self-propelled souls, not one of Plato's dogmas would follow. Giving these souls the title "gods" may look like a mere matter of courtesy or terminology; but this is not the case. As long as we call them souls, they might well be fellow sufferers, as Eastern wisdom has it; some might be evil, as Plato himself says at one point; or at the very least they might not deserve worship. Plato's proofs fail, but it is interesting that even the great Plato should have incuned such a mass errors; the more because the very same mistakes are found in his successors. Indeed, the very argument that Plato used to prove that there are many gods was used by later writers to establish the existence of the one and only God. Some did not even bother to adapt it. (Walter A. Kaufmann – Critique of Religion and Philosophy)  
The most important argument from Feser's point of view is that all worldly things are composites. And composites supposedly never have independence but are entirely dependent on a Thomistic God. This is Feser's main argument for which he would put anything in the balance. John Deck sees it the other way around. A dual thing or a composite thing can never be completely dependent on anything. If John Deck is right, Feser's entire project is shattered in an instant. Anthony Kenny sums up John Deck's essay as follows:
Aquinas describes the relation of creatures to their First Cause as one of total dependence. In his paper John Deck argues that this is inconsistent with the distinction between essence and existence which Aquinas attributes to all creatures. For the substance or essence of a created thing to be to it "through itself", he argues, is incompatible with the total dependence of the creature on the creator. (Anthony Kenny in the preface to Aquinas – A Collection of Critical Essays edited 1969 by Anthony Kenny)
Now I'll let John Deck speak for himself:
St. Thomas's account of the creature is thus inconsistent. For the substance or essence of a created thing to be "to it through itself" is incompatible with the total dependence of the creature upon the Creator. 
If the creature, or the essence or the substance of the creature, is considered as a receptor of existence, a semi-independent term of the creature-Creator relation has been posited. The creature, or its essence or substance, is being considered as something which has some shade of being in its own right and receives existence from the Creator. 
The entire substance of the creature is the effect of the first agent. For the effect of this agent, "there is no receptive subject." [Aquinas] Therefore (what is not said here, certainly), the creature can be, or have, no essence - since essence has been called, exactly, a receptive subject. Or - to save something at this point - the creature cannot be, or have, an essence distinct from its existence. There can be no essence-existence composition in the creature. 

In one noteworthy instance, the composed creature has come to grief. If he is composed of essence and existence as St. Thomas explains them, he cannot be totally dependent. I should like to suggest that if he is "composed" at all-if there is any duality in him with respect to his relation to his Creator, he cannot be totally dependent.


What can be made of "the creature is related to the Creator" if the relation is total dependence? It cannot be that the creature is one and his relation to the Creator a second. If the creature is to be totally dependent, there can be nothing in him other than his relation to the Creator. Perhaps one should say that the creature cannot be a term of the relation (for then, cut it as you will, he will be in some fashion independent), he must be the relation. If the notion of relation is relevant here, it would seem that "total dependence" cannot be said in any other way. Those who wish to say that the creature is totally dependent must take account of "otherness." If the dependent is not other than that on which it depends, dependence itself disappears. So it might appear that the creature is composed of otherness and dependence. But, once again, dualizing the creature hurts rather than helps. The otherness between the creature and God, by being "explained" in this way, merely reappears at once as the contrast between two parts in the creature. Meanwhile, one part, the "otherness from God," by being contrasted to dependence, begins to escape from dependence. The otherness of the dependent cannot be different from the dependence of the dependent. There can be no dependent which is not other. Conversely, otherness for a creature is itself totally dependent. Thus, for a creature, otherness and dependence cannot be two distinct parts or the cause, or effect, of two distinct parts.


In general, a two-part structuring of the dependent (for convenience, "the creature") is incompatible with total dependence. The two parts will be rendering some internal difference within the dependence of the creature upon the Creator. It would be pointless to regard the creature as double if the two parts are considered on a par, and no one in fact has done this. This would too obviously be a multiplication without necessity. If the two parts are unequal, what can make them unequal? Only their connections with the Creator. Perhaps one is "closer" to the Creator-another more remote? Is it a partial eluding, an escaping however humble from the Creator's agency? Or is the more remote a radically deficient being that "really needs" a boost from the Creator? Then what about the more proximate part? Can this, in this respect, be any different? If the creature is taken as dual, there will be an uneasy shuffling between these two positions: the more remote part needs the Creator more, or the more remote part needs the Creator less. If it needs him more, the more proximate part needs him less-and here there will be a tendency to take the more proximate part of the creature as part of the Creator, to the detriment of the whole notion of creature. If the more remote part of the creature needs the Creator less, this can mean only that it has a trace of independence.
In short, a totally-dependent creature cannot be dual. If the creature as a creature is composed of two unequal parts (act-potency; form-matter; existence-essence; dependence-otherness; the "from God" and the "its own"), one part must escape from the divine causality and so from dependence. If there is any total dependence anywhere, either of creature upon God or of anything upon anything else, the dependent must be a one in respect to that upon which it depends. (JOHN N. DECK - ST. THOMAS AQUINAS AND THE LANGUAGE OF TOTAL DEPENDENCE. In: Aquinas – A Collection of Critical Essays edited 1969 by Anthony Kenny)
So if there is a complete dependence somewhere, the dependent must be one in relation to what it depends on. But from this, it cannot be concluded that what is one must also be completely dependent (in whatever sense) on whatever (or some oneness things might not depend on anything). With regard to composite beings, one could say that the dependent part of a mundane being is dependent on the independent part of another mundane (composite) being (or on one of the many possible things being totally one and independent). Then there are several good ways to exclude God.

Now after some excursions, we come to the second additional assumption after Feser has turned his attention inwards using the example of the arm. The second assumption concerns the so-called part-whole relationship of substances or things. Feser suddenly sees the relationship of the parts to the whole as a relationship of efficient causality. The parts are the efficient cause, and the hylomorphic whole is caused and effected accordingly. But this is anything but Aristotelian. In Aristotle’s case, this relationship is clarified by the formal and material cause and not, as Feser assumes, by the efficient cause. The efficient cause of a rubber ball is not its parts (for example, its atoms), the efficient cause is the factory worker with his machines. Moreover, the atoms of that manufactured ball neither move completely loose and random nor do they separate (themselves) from one another because they are kept structured and integrated into a uniform whole due to the formal cause, which makes them possible as parts in the first place (the form is not only the outer shape but also the inner structure and structuring). This becomes much clearer in the case of the metabolism of an organism, where the form remains the same while the matter changes in the sense that old material is gradually released from the organic structure, and new material is directly assimilated in return (according to Aristotle, the form of humanity contained in my semen is even the very efficient cause of my son's coming to be. In living beings, this form is passed on from generation to generation, from parents to children. Many times in Aristotle the formal cause is numerically identical with the final cause and the efficient one. It must, therefore, be understood as something active in contrast to the passive, inert, and dormant material cause). As a supplement to the above, it can be said that artifacts do not actually provide a good example to illustrate a holistic whole, as they are true reductive compositions. Crystals or minerals or chemical elements would be better suited for that. 

So the relationship of the parts towards a (hylomorphic) unitary whole cannot be a relationship of efficient causality. If anything, it would be exactly the other way around, especially in the case of movement. Parts of a (hylomorphic) whole may indeed stand in an efficient causal relationship with one another, but the whole (as perhaps form plus all matter) as something ontologically (not temporally) preceding always stands above matter, that is, also above its parts in the hierarchy of causal significance and power. Consequently, the concept of self-movement (better said, pure individual intrinsic movement without there being a self that moves itself) of or by a human (intellectual soul), an animal (soul), a slime mold (soul), a mushroom (soul), a plant (soul), a crystal (soul/form), a chemical element (form) cannot be an illusory concept for Feser, a concept that only wants to deceive and that pretends to represent something real. But then Feser cannot deny or relativize this kind of movement regarding the First Way to God. Is the power of man to move autonomously real or not real? Does self-movement exist only nominally, i.e. in name only? Is the following sentence nonsense?
Life, says Thomas Aquinas in his commentary on Aristotle’s book on life, the De Anima, is essentially that by which anything has power to move itself-—taking ‘movement’ in its wide sense. (Herbert McCabe – On Aquinas)
Here's more from McCabe:
In every case, though, at whatever level we are using the word 'life', we are speaking of what at some level has the power to move itself, not just to be at the mercy of others. In this tradition living things are auto-mobiles, self-movers. And in this tradition having an anima or 'soul' (a term which is also, of course, used analogically) means being, at some level, able to move oneself. All auto-mobiles, at whatever level, have souls—at some level of the word 'soul'. So, in this way of talking, potatoes and cockroaches have souls.
All living things that are self-moving, at least in the sense of moving physically, must be, as Aristotle pointed out, complex. They have to be made up of parts so that when one part moves another the whole thing moves the whole thing. A leopard is self-moving because the action of one part of it, the brain, which is an action of the leopard, moves another part of it, the legs, which is a movement of the leopard. So it is an action of the leopard (using its brain) that causes a movement of the leopard (using its legs). It is leopard moving leopard—it is selfmoving. Now all this depends on both brain and legs being parts of the leopard, so that an action of the brain is not just an action of this lump of grey matter but is also an action of the whole leopard; and similarly with the movement of the legs. This implies that if you amputated the leopard's leg, separated it from the whole to which it belongs, it would become a different thing altogether. Before the amputation, if you were so ill-advised as to punch the leopard's leg you would simply be punching the leopard: that is what it is you would be punching. After the amputation you would not only not be punching a leopard, you would not even be punching a leg. A detached leg is not a kind of leg, as a dead cow is not a kind of cow or a forged five-pound note is not a kind of five-pound note. And this is not just because we mean by the word leg something that is a functioning organ of the animal; it is because in the living beast the leg is a functioning organ of the animal. It is because we think this that we think the leopard is self-moving and thus a living thing. It is because we do not think that the wheels of a car are, in this sense, essentially functioning organs of the car that we do not think that a car is alive. I mean we think of the leopard as the natural unit of which the legs and brain are essentially parts; being a part-of-the-leopard is what it is for the leg to be what it is; it has its existence as what it now is by being a part of the leopard. The whole leopard, so to say, comes first. The parts are secondary. If the leg ceases to be part of the leopard it will turn into something completely different, as mutton is something completely different from a sheep. So a leopard is alive because it has organs which exist as what they are precisely by being organs, being functioning parts of a prior whole. (Herbert McCabe - On Aquinas)
The Aristotle expert Wolfgang Welsch gives an example with plants:
Let's look at the growth of plants. We can still say, at least in everyday speech, that a tree wants to grow. You can almost see that on some trees: That tree there was restricted in its development by other trees, but then it found a clever way to develop itself by not growing straight, but crooked, by taking detours in order to obtain enough light for its development. In such cases it is evident to us that the movement is not simply something caused from the outside - in this case it was rather blocked from the outside - but that it lies in the nature of this being and has its drive from this being itself. (Welsch, Wolfgang. Der Philosoph: Die Gedankenwelt des Aristoteles; translated from German by myself, The Philosopher: Aristotle's world of thoughts)
And what about the next passage, which deals with the inorganic:
To further clarify Aristotle's thesis that the natural has a principle of its movement and rest in itself, let us choose another aspect - this time a quite famous and at the same time controversial one. I mean Aristotle's doctrine of the natural place, of the locus naturalis. When a stone is thrown up, it falls back to the earth. Nobody doubts that. But how do you explain this return to earth? We modernists explain it as an effect of gravity. The gravitational pull of the earth retrieves the stone. Because of it we were able to throw up the stone only a little bit. Aristotle, however, gives a completely different explanation. He knows nothing about gravity. He says: The stone has a natural place, and this is the earth. To be there belongs to the essence of the stone. Therefore, the stone wants to remain on the earth - its natural place of residence. That is why you have to use strength to lift it up and even to hurl it up. But the stone retains its natural tendency to be on earth; it is responsible for its falling down again. [...] So, in Aristotelian terms, we speak quite correctly in everyday life when we say "the stone falls down" - the stone is actually the doer [agent] of its return movement (and not the victim of gravity). Let us look at another example. If you enclose air in a container, you can press it a little under water, but you have to use your strength. According to Aristotle, this shows that the air wants to go up - back to its natural place. As soon as you pull your hand away, the container rushes up - the air also pushes itself energetically to its locus naturalis. (Welsch, Wolfgang. Der Philosoph: Die Gedankenwelt des Aristoteles; translated from German by myself, The Philosopher: Aristotle's world of thoughts)
This could also explain self-motion:
But it seems that at least things in perpetual motion could be self-movers. It seems, in Aquinas’s Aristotelian terms, that they could be at every moment things actually in motion and potentially in motion in the immediate future, their changing potentialities being continuously actualized by the action of their immediately antecedent actualities. (Jordan Howard Sobel - Logic and Theism Arguments: For and Against Beliefs in God)
George A. Blair summarizes it all:
In fact, the First Way cannot deny that there are non-processes that are active, because it argues to one. But in point of fact, both Aristotle and St. Thomas held that there are acts that seem to be processes and are not, and yet are not the First Mover. These are transitions of a sort, but not transitions from potency to act. The most common example they give of such a transition is that of not seeing to seeing. St. Thomas, for example, says the following in distinguishing a process like getting hot from this kind of transition:

"And because everything that is in potency, to the extent that it is such, is imperfect, then the former kind of process is the act of something imperfect. But the latter “process” is the act of something perfect: it is the operation of the sense that is already in act, because of its species [i.e. because of what determines it to see this and not that] … . This sort of “process” is properly called “operation.” (In De Anima, III, 12)" 

This type of pseudo-process, then, is a transition from act to act, and the being does not acquire something that it does not already have. Another example would be actively thinking about some fact that one already knows, but was not thinking of before. One is no greater for thinking about it, because one already knows it. One could say that there is a change in some sense going on here, but it is a peculiar one, one that could be called, in modern terms, a change of phase rather than a change of state. Now such transitions are most obvious in the operations of living things, but are not confined to them. Hence, if St. Thomas admits the existence of pseudo-processes even in inanimate nature, he would handle the Newtonian “refutation” simply by saying, “But that is not what I am talking about.” 
The capacity for doing work is obviously the power to cause a real difference in something, or is active potency, not passive; or, in other words, energy is act, not potency. The fact that energy is measurable does not militate against this; if it is measurable, it is the principle (to use Thomistic terms) which is limited, not the principle of limitation, i.e. it is again act. And if one looks at what is called energy (heat, light, etc.) one finds that they are what Thomists would refer to as "accidental forms," which are acts, not potencies. Actually, energy as used in modern science is a general term meaning "act (in the Scholastic sense) insofar as it is subject to quantitative limitation." 
But the instability of the “big bang’s” material could have been due to the gravitational collapse of the same material into a single, unstable body. That is, if we assume that the expansion of the universe as we know it will ultimately reach a term where the force of the initial explosion which creates the expansion grows weak enough to be counterbalanced by the gravitational attraction of the galaxies for one another, then the universe will begin to contract, slowly at first, then faster and faster, until finally it will collapse back into the primordial fireball, and we will have another “big bang,” and the whole thing will start all over again. The point here is that this alternate expansion and collapse of the whole universe is another of the pseudo-processes we spoke of earlier, which does not imply that energy needs to come from outside the system to explain it. Any cyclic kind of activity, where each cycle exactly repeats the cycle before it, is a kind of equilibrium, as is indicated by the fact that if it is not interfered with from outside (i.e. if no energy is introduced into it), it will go on that way forever. The system is simply trading off its own energy internally from one part to another; but the system as a whole does not change its energy-level at all. It is active, in other words, but not really in process.


And this leads us back to the First Way in the light of St. Thomas’ own philosophy. Since he admits, as was said earlier, that there are transitions that are not processes, then all the First Way really argues to in Thomism is to a living being, which is defined as one which can set up its own process. (Summa Contra Gentiles, IV, c. 20.) Of course, the living being does not "move itself" (movere se) in the respect in which it is in process, but processes like growth or movement of the limbs are initiated from the soul, or the “first act” within the being, and so have as their cause one of those transitions from act to act.


It is true that he would hold that not every act of the human mind is a pseudo-process; learning, for instance, is a transition to a condition that did not exist before, and so is from potency to act in a sense that thinking about what one learned is not. But an argument based on this either is the “Frank-is-the-father-of-John” argument, for which no “first” is necessary, or is the argument from finiteness of existence, which was not really presented in the Five Ways. 

Take a series of increases in heat, for example. The objects in the room are getting hotter because the air in the room is getting hotter; the air is getting hotter because the element of the electric heater is getting hotter; but the heater is getting hotter because electricity is being allowed to flow through the resisting wires, and is doing work on them. But it flows because it is going from a higher to a lower potential, and it does this spontaneously, without having to be pushed. So the “first mover” of this sequence is the electricity at its high potential, not the Almighty. One could object here that we have not accounted for how the electricity got to this high potential, and so we have not really stopped the sequence. But we have, in the sense that is relevant to the First Way. Granted, in order to make electricity do work, the energy level of the electricity must be raised; but one can store this electrical energy in a battery, for instance, after one has increased its energy, and the cause of the energy in the battery can cease to operate long before the energy in the battery is released. In other words, we are now in a sequence analogous to that of Henry’s being the father of Frank and Frank’s being the father of John, where there is no necessity of going outside the set in question, and where there can be an infinite sequence. The reason is that the battery ultimately got its excess energy by reason of the energy loss of something else, and, according to the First Law of Thermodynamics, the total energy of the interaction remains constant. It was for a reason such as this that St. Thomas believed that it was impossible to prove philosophically that the world began. (George A. Blair – Another Look at St. Thomas' "First Way")
Thus artifacts like a heater must also be understood hylemorphically. According to Thomism, all bodily substance, living or not living, is composed hylemorphically, i.e. by a formal principle (in humans it is the Aristotelian soul) which actualizes, in a definite sense, the potentiality of matter (in humans it is the material body). But hylomorphic unity is still the main thing. Form and matter are only separable in thinking. In reality, they are inseparable and even indistinguishable. At most, form and matter are conceptually distinguishable within or on the basis of the ontic one (living or non-living) being (of course, God is not meant here), but they exist actually unseparated (all this says the German Aristotle expert Wolfgang Welsch). So they are one in the most obvious way, and it is precisely this oneness that characterizes what really exists (natural individuals). By the way, a proof of God based only on a purely conceptual composition of things is in itself very questionable (form and matter are mere abstractions in our heads and nowhere else)

Nevertheless, hylomorphism is not a theory without problems (more convincing would be a theory of morphism without the Aristotelian hyle). Apart from the fact that it probably only goes together systematically with naïve realism (direct realism), there are other difficulties (because hylomorphism is basically very ambiguous, among other reasons due to the fact that sometimes the form is something concrete, sometimes only abstract) as discussed in the following link:

Bernard Williams sums up the ambiguity of hylomorphism (concerning the mind) quite well:
Hylomorphism earns its reputation as everybody’s moderate metaphysics of mind, I believe, by in fact wobbling between two options. In one of them, soul does basically appear only adjectivally, and while the doctrine is, so far as I can see, formally consistent, it is only a polite form of materialism, which is cumbrous, misleading, and disposed to point in the wrong direction from the point of view of deeper theoretical understanding. It also has precisely this disadvantage of readily sliding into the other view, in which soul tries to transcend its adjectival status, and become the bearer of personal proper names: in that form, it yields us a notion of person which is a type-notion. We might one day need such a notion: but it is not what hylomorphism wants, and hylomorphism itself is not well equipped to help us to understand it. (Bernard Williams - The Sense of the Past)
In summary, one can say that according to Aristotelian basic assumptions parts do not cause the whole (reductionism). Moreover, a possible relationship of dependence - a dependency in whatever way of the whole on the parts - cannot be a relationship of motion and creation or of creating motion. The sum of the parts does not actualize a supposedly potential and secondary whole by moving and creating. 

As Mccabe already pointed out, the whole comes first (or is prior and has primacy), metaphysically or ontologically speaking, and, according to Blair, also transitions from act to act (whenever a change in the Aristotelian sense occurs, something must remain in actuality from the beginning to the end of the change, but as we have seen, it does not have to be a god; it could be 1. the cosmos as a whole and thought of as a closed system, 2. the integral individuality of living or even "dead" inorganic beings, entities or powers, or 3. mere Democritean atoms)

If parts are only parts in a whole, then logically the parts cannot cause the whole (at best, one could say that entities have accumulated in such a way that a whole has emerged from them or from the accumulation of them, and since then these entities have become parts which all form a unit together by a unifying underlying principle, namely the form of the whole). But it should not be denied that the whole is in some sense dependent on the parts, however, this dependence is different from the dependence of the parts on the whole. 

Parts in a holistic whole have a common or shared inner unity so that a determination of a part will always have something arbitrary and artificial about it, while parts in a reductionistic whole have a discrete and somewhat estranged or dissociative relationship with each other (and with the whole itself). In the latter sense of a whole, I could lose my (individual) humanity if some parts are missing or incomplete, as was discussed in the case of the comatose patient Terri Schiavo. This would not be Aristotelian. The actualizing generic form belongs - as long as one wants to argue as an Aristotelian - to the part-whole relation. Whoever wants to detach it from this relation is dishonest

If the Aristotelian form of man belongs to the whole of man, a form which, after all, constitutes the identity of man at all times of his life as something always constant and continuous, no matter what happens to him as long as he is alive, then it seems impossible to consider the parts as ontologically prior to the whole.

A reductionistic theory is any theory that assumes that what exists is something that can be broken down or disassembled into "parts" or "elements" without any loss (in order to understand the "pseudo"-wholeness)

Holism is a compelling and powerful argumentative counter-approach, according to which an explanation of something can never be reduced to the description of the behavior of its "parts" or "elements" - the object of investigation must be considered as a whole, for it is very likely that the unity of its wholeness is metaphysically and intrinsically given. A whole cannot be treated as the mere sum of its "elements", because although it has such elements, they are by no means discrete. There is more information on this subject in the appendix.

holism, the table in front of you does not derive its existence from the sub-atomic particles that compose it; rather, those sub-atomic particles derive their existence from the table. ( 
Elsewhere, Feser also thinks holistically:
For example, if a stone is a true substance, then while the innumerable atoms that make it up are real, they exist within it virtually or potentially rather than actually. What actually exists is just the one thing, the stone itself. (Edward Feser – Aristotle's Revenge)
This would be the logical consequence:
Indeed, Feser reasons, such parts cannot be present in actuality since their essential properties are not present when they are part of the substance. But since (per one of Feser’s premises) only actual things can actualize something’s potential for existence, it follows that the parts Feser adduces cannot causally actualize the existence of the substances they compose. (Joseph C. Schmid - Existential inertia and the Aristotelian proof)
Basically, Feser does not really believe in the ontologically prior efficacy of parts at all.

Intuitively, one rightly assumes that once holistic things begin to exist, they will persist for some time:
I say that [a] chair’s existence at t + ε is fully explained by the actualization of the potential, possessed by the chair at t, to continue to exist through t + ε, and the absence of anything that intervenes to prevent the realization of this potential. (GRAHAM OPPY - On stage one of Feser’s ‘Aristotelian proof’)
most things naturally tend to remain in existence. (Anthony Kenny - Medieval Philosophy)
On the non-Aristotelian side I can only agree with Fox ITK, who says the following (the full comment and the link to the youtube discussion between Feser and Oppy are in the appendix):
Something that confuses me about this argument from ‘being composite’ used to support the idea of divine conservation. It seems as if it’s just an outright denial of the possibility of simples which are not composed of parts which I don’t think there’s a good reason to reject[.]
The two other cosmological proofs of God have already been refuted once and for all by Kant. You only have to abstract Aquinas arguments from many details to get to the cosmological idea that Kant finally goes into:
Kant approached the cosmological argument differently in his Critique of Pure Reason. He argued that it is not really an empirical argument, but a concealed version of the ontological argument, for it invokes the concept of a necessary being to serve as a ground for the contingent universe. But the concept of a necessary being is shown by discussion of the ontological argument to be empty.
Some of Kant’s critics use a technical philosophical distinction to answer him. They claim that he has mistaken the idea of a logically necessary being with the cosmological argument’s requirement for a metaphysically necessary being. The distinction works in rather the way that equivocation over the term ‘necessary’ worked in relation to Dr Pangloss’s nose, as explained above. A logically necessary being is one that must exist. A metaphysically necessary being is one that must exist in order for the universe to have a stopping-point for the regress of causes, that is, as a ground on which contingent existence can rest. Thus, metaphysical necessity is relative, logical necessity is absolute.
But Kant can reply that this attempt to restrict attention to the ‘necessary condition’ sense of ‘necessity’ is spurious, because what is being proposed is a being that has to exist, whether our ground for asserting this is the definition of the being (as the ontological argument has it) or the contingency and causal dependency of the world upon such a being (as the cosmological argument asserts). Any counter to the claim that the idea of a necessary being makes sense is therefore a counter to both arguments.
(A. C. Grayling - The God argument)
Walter Kaufmann, with the help of Kant, criticizes the concept of a necessary being:
A “necessary being” is comparable to a “valid being” and to a “necessary triangle” and a “neurotic triangle.” We understand the adjective and the noun, but their conjunction is illicit. As Kant noted in his Critique of Pure Reason (B 620ff.), the adjective “necessary” has no applicability to beings: “One has at all times spoken of an absolutely necessary being, without exerting oneself to understand whether and how one could even think of such a thing. … All examples are, without exception, taken only from judgments, not from things and their existence. But the unconditional necessity of judgments is not to be confused with the absolute necessity of things. For the absolute necessity of a judgment is only a conditional necessity of the thing or the predicate in the judgment. The previously cited proposition does not assert that three angles are altogether necessary but rather that, assuming the condition that a triangle exists (is given), three angles also exist necessarily (in it).”
A “necessary triangle” is obviously in the same category with a “neurotic triangle.” But “being” is such a general term that it is less obvious that “necessary being” is in the same category, too. Yet there are predicates that cannot be ascribed to beings, “Valid being,” for example, and “cogent being” are as illicit as “necessary being.”
Nor will it do to substitute for “necessary being” some such phrase as “a being that necessarily exists.” Even as “valid” has meaning only in relation to some logical or legal framework, “necessary” has meaning only in relation to presupposed conditions. It makes sense to say that, if A and B exist, C must necessarily exist. But taken by themselves, the last four words do not make sense.
 (Walter Kaufmann - Critique of Religion and Philosophy)
So this is Kant's main argument:
‘Reason recognises that only as completely necessary which follows of necessity from its concept.’ ‘Absolute necessity is a necessity that is to be found in thought alone.’ ‘If. . .the absolute necessity of a thing were to be known, this would have to be a priori from concepts, and never by positing it as a cause relative to an existence given in experience.’ (quoted from Jonathan Bennett - Kant's Dialectic)
The idea of an entity of pure being in itself by no means would imply that this entity really exists. The equation of essence and existence cannot escape the failure of the ontological proof either. To say that something exists by definition and not in fact means that due to the way a certain term is defined, existence is part of the term. Pure being would then exist by definition because existence would be part of the definition of a real pure being. Whether this real pure being in fact exists, however, is another question. Thus one cannot argue something into factual existence by reifying speech. 

No proof of God is ultimately convincing from a religiously neutral perspective. The idea of God, defined as that which is absolute in every possible respect, as that which can no longer be derived from anything in an absolute sense, can logically no longer be completely deduced in a course of evidence on a sheet of paper (without completion, there will always be doubts). When the theist assigns certain qualities to his God, such as being partly incomprehensible, having necessary existence, being uninfluenced by or free from the principle of sufficient reason, having (in a mysterious way, endlessly intricate) simplicity and more, then the atheist has every right to relate or attribute these qualities to the cosmos as a whole or to its parts. If the atheist did not have this right, he would lose any debate with the theist. The theist would always checkmate him. It is known that if the theist places the necessary existence in a transcendent being, the atheist wonders why the necessary existence cannot apply to the universe itself or to some of its elements. Moreover, the theist accuses the atheist of stopping at brute facts, which would violate the principle of sufficient reason. But the atheist can only think of God as a gigantic (transcendent, mystical, magical, fabulous) brute (just is) fact, to whom that principle cannot be applied (I define brute as immune to the principle of sufficient reason and contingent as ephemeral). I generally think that when theists and atheists or agnostics discuss with each other, they should all have access to the following argumentation cards:

Appeal to analogical predication (without this appeal, the Thomists become mere agnostics; when the materialistic naturalists speak of information in organic nature or of algorithms in the universe, then this is also to be understood only analogously)
Appeal to extrinsically or relational properties (the Thomists use this one wastefully. After all, the triune God is also supposed to be a structure of relationship(s), without losing its simplicity. Then I can possibly transfer the basic idea of this structure to other things that work in a naturalistic way)
Appeal to mysteriousness (the naturalist says and must also say that many things are mysterious, above all because our mind did not come into being to fathom the true nature of the universe)
Appeal to immunity of something to PSR (appeal to one brute fact or many ones, which the Thomist will never voluntarily grant the naturalists, but which he must do if he still wants to talk to them. Even aspects in nature I could see as irreducible brutish simplicity) 

Otherwise, it would be an unfair discussion if only one party had access to these cards. Hence the agnostic stance is the most rational:
There is no reason which is nobody's reason and which belongs, in Adam Smith's phrase, to an 'impartial spectator'. In this respect, there are no impartial spectators, nor are the differences between believers and unbelievers due to mistakes of logic on one side. (LUBOR VELECKY - The Five Ways)
A problem with Feser is that his concept of causality, which he uses for the first Three Ways, already presupposes God. For Feser says that a cause is always teleologically directed towards its effect. And according to the Fifth Way, teleology is only possible under the assumption of a god. So Feser must either deny the validity of the Fifth Way so that the first Three Ways do not suffer infiltration from what is yet to be proved (otherwise, we would have a petitio principii) or he would only be allowed to talk to atheists about the Fifth Way. Basically, we would then only have a discussion about the semantics of the term causality, that is, about a purely conceptual issue.

There are at least two meanings of the concept of causality which can be formulated as follows: A is the "initiator" of B or a change in B. And (relational causality): Given the occurrence of B, A must necessarily have occurred. I don't think you have to accept teleology for the former meaning. The concept of natural necessity would also be perfectly sufficient: A brings about (a change in) B necessarily. Or to put it another way: A necessarily produces B or a change in B. That's enough to express the inevitable natural regularity. The concept of teleology would only needlessly and superfluously introduce a speculative element and add nothing informative beyond the assured regularity. The medieval nominalists also omitted the concept of final causality and did well in explanations only with formal and efficient causes. If we wanted to say that the first meaning of causality must indeed include teleology, then this could lead to an extremely fatalistic worldview (teleological fatalism).

For if the microcosm of the world (Feser's "ever-deeper levels of reality") consists only of causal chains (essential and accidental) that are teleologically ordered, then you just have to proceed all the way from the deepest layers to the top (bottom-up), and you will unavoidably see that the entire world is teleologically structured since nowhere is anything non-teleological left. The world, including humans and their intentions and acts, would be as it needs to be. Every moving and moved thing would be directly or indirectly for (the sake of) every other thing, especially if the world has a beginning and an end. Cosmic harmony would prevail. One can start from the macrocosm as well, i.e. from top to bottom (top-down). According to Feser, the universe as a whole has an efficient cause ("indeed the universe as a whole, must be sustained in being here and now by a cause outside it, a First Cause which upholds the entire series"). But then it will also have a final cause (if Feser would deny this, he wouldn't be credible anymore). Everything below the one top final cause serves as its subordinate (final) cause (even human intentions made after decision-making, otherwise they would be mysteriously of extra-worldly origin). Only an outside God could disrupt the perfect teleological structure. But why should he corrupt his own work? Instead of a world that is governed mechanically or whose processes occur purely out of necessity, we are dealing here with a completely predetermined world in which each and everything by itself joins the (teleological) whole seamlessly, but fatalistically. We would have a world entirely of expediency. There could not be anything that would in any form indicate a non-teleological deviation from something. Any supposed deviation would be perfectly normal, natural, and totally appropriate, even laudable. If both microcosm and macrocosm are to be interpreted exhaustively in a final causal way, then absolute morality with real culpability (for Thomists, it is natural law) takes its leave (in a relative sense, of course, you can still have moral rules).

Feser suggests that the cause is one thing and the effect is another. He gives the example of a brick and a broken window, while the many panes of glass lying on the floor would still be many things that belong to the effect. When I now say that the brick was aimed at destroying the window, it sounds very strange. It will only make sense if a person, in this case, a vandal, deliberately threw the brick to destroy the window. The brick would carry the goal of the vandal within, figuratively speaking. What Feser says below is not very meaningful:
Suppose you asked your uncle (or whomever) what caused the broken window. Unless he’s a philosopher, he’d probably say, “The brick did” – the brick, not “the event of the brick’s being thrown.” In other words, for common sense it is ultimately things that are causes, not events. Aristotle would agree.
I think the uncle would rather say some ***hole did it (with a brick). If he mentions the brick itself as the cause, then so: It was a brick that suddenly came flying in (an event). Let's leave aside the vandal and explain the flight of the brick simply by putting it in a flying motion due to wind or lightning (a natural event), then the goal of the brick would be rather, to put it simply, to complete its trajectory. In this case, the goal would refer to the brick itself and not to anything else (the trajectory is probably not another thing). Finally, the goal of the window is not to clear the way for the brick and get broken but to remain stable. So there are two different goals that collide. In other words, two things that each have their own purpose clash together. The result of this encounter is the destruction of the window (not the goal of the window) and the slowing down and course change of the brick (not the goal of the brick). Natural effects resulting from several causal factors (this is probably the case for most effects) are unlikely to be considered teleological unless one sees pure harmony in everything. This means that neither the cause of a motion resulting from multiple confrontational causal factors can be understood teleologically, nor any effect that this motion might have. This motion causes something only in a teleology-free efficient way, or even just mechanically. So the motion itself is to be understood only as naturally necessary. 

Furthermore, Feser claims that the moon is teleologically aligned to move around the earth. How does Feser know that? His claim comes merely from Aristotle's outdated theory of planetary motion. Perhaps the movement around the earth is just a resulting movement from the confrontation of several forces. Who knows? The moon may want to fly goal-directed to earth but is then repelled by an electromagnetic force. Or the moon wants to leave its orbit completely by (its) centrifugal force and is simply held back by earth's gravity. Feser’s making it too easy here. Why shouldn’t two teleological forces confront each other so that a resulting and coerced movement emerges that is not actually aspired to by both forces (a movement to which the forces were never directed, to which they had no natural disposition)? Feser imagines the universe to be too harmonious. His other example of the electron moving around the atomic nucleus is also a bad example of teleology since an atom and its interior are by no means a matter of experience.

Feser likes to talk about matches that aim at fire when he talks about teleology. That’s again not a good example because it’s an artifact that is always purposeful (an artifact always requires a human to use it according to its made purpose). If we look at the match only materially and naturally, we have a chemical composition that is hardly specifically fire-orientated, at least not more than many other substances. Then there is another example of, so I believe, fragile glass, which allegedly has the telos of breaking, that is, which is directed towards breaking. As far as I know, this can only be said of substances that decay radioactively. But not of glass or any other material that can break easily. Feser sees the property of being able to break quickly in an absolute sense, although he should put it into perspective. The very fragile breaks only because of specific external influences, which I could imagine being so weak, that the fragile no longer appears fragile, but hard as iron. In a certain context, a thick disc made of titanium can be fragile as well. Fragility is absolutely context-sensitive (in a certain context, the fragile can even be unbreakable in a practical sense). To understand the true telos of a thin glass that allegedly has the directional disposition to break in our world, it would have to be completely detached from everything. Then you'd have to see what happens. But that, of course, is not feasible. In context, the glass can be said to have all sorts of teleological dispositions, whereby its fragility does not stand out at all (in comparison).

Feser says that the final cause of the heart is the pumping of blood. Shouldn’t it be better to say that the final cause is just pumping (exercise of a certain muscle movement), because the heart doesn’t care about what is being pumped? Or I can put it more generally: The heart pumps to ensure self-preservation, but ultimately it only does so to keep my expansionist urge (Nietzschean) going. So the heart pumps for the sake of gaining power. 

Teleological statements can never be easily made, but Feser seems to see it differently. He thinks he knows things that hardly anyone else seems to know. That is completely presumptuous. In addition, Feser is extremely selective in his teleological considerations. 

The common objections against teleology are, that teleological explanation reverses the orthodox order of cause and effect, that teleological explanations involve the illicit attribution of human mental characteristics to things other than human beings, and that accepting teleological explanations would bring scientific research to a halt, at least in some fields. These objections have definitely some merit. 

Feser does not want to have anything to do with Intelligent Design à la Paley in his teleological proof of God, i.e. in his concept of teleology. Here he is already in conflict with people from his own (Catholic) ranks:
In his article “Teleology: A Shopper’s Guide,” Edward Feser attempts to explain why Aristotelian-Thomistic (A-T) partisans of the Fifth Way generally reject the positions of the Intelligent Design school and distance themselves from Paley. In this note, I argue that on a number of points Feser fails to accurately convey A-T views pertinent to reasoning to the existence of God starting from teleology or action for an end in nature. (Marie George - An Aristotelian-Thomist Responds to Edward Feser’s “Teleology”)
Taking an Aristotelian rather than Paleyite position, Professor Feser emphasizes the difference between organisms and artefacts. His problem with Paleyism is that natural objects are treated as artefacts, as without substantial form and intrinsic teleology, and with their teleology imposed on them from without such that any forms are merely accidental. Having confused natural objects with artefacts, Paleyism approaches God through the wrong sort of teleology, extrinsic rather than intrinsic. But where his Aristotelianism leads Feser in regard to God is an example of a seemingly apophatic rather than analogical theology: God cannot be called an “artificer.” Feser says, “Natural objects are not a kind of artefact and hence God’s relationship to them is not that of an artificer.” I reply, however, that the Christian theologian has reason to speak by way of analogy of the Trinitarian God as an artificer and creatures as divine artefacts, and that theological reflection on this analogy can suggest to Professor Feser reasons, even philosophical reasons, to modify or rather clarify his seemingly apophatic conclusion. (SIMON FRANCIS GAINE - God is an Artificer: A Reply to Professor Edward Feser)
By the way, the reference to the analogous character of theological statements only obfuscates the fact that they have no precise conceptual meaning and that one wants to keep the door open to say that the whole matter is not meant that way when somebody argues against them. Analogy arguments are, in principle, weak arguments. Moreover, an analogy would have to be grounded in a further relationship. But how is that relation to be understood? Analogically? But somewhere the analogies must stop, otherwise, we have an infinite regression: this analogy explains this analogy which explains this analogy and so on. Paul van Buren rejects the analogical theory of God-talk because
the cognitive approach requires speaking of that which it admits is ineffable. It involves speaking of God by analogy, yet it is granted by its proponents that they cannot say to what extent its analogies are apt and proper[.] (Paul M. van Buren - The Secular Meaning of the Gospel Based on an Analysis of Its Language)
And Walter Kaufmann is also critical:
The attempt to salvage religious propositions by admitting their literal falseness while maintaining their truth, provided only that they are interpreted as analogous or symbolic, must fail. It ignores the essential ambiguity of the propositions it would salvage. (Walter Kaufmann - Critique of Religion and Philosophy)

Here's another opinion:

To cover the nakedness of [the] inconsistency with talk of the merely „symbolic" or analogical meaning of theological terms is only to announce one's intention of not standing by any affirmations or denials which one makes in these matters. Even analogical affirmations should commit one to something. (Ch. Hartshorne - The Logic of Perfection)
Feser knows only too well that if he made concessions to Paley, he would be vulnerable to the objections of David Hume:

Hume’s reflection and acumen alone stood the test, even in this case; in his “Dialogues on Natural Religion”, which are so well worth reading, this true precursor of Kant calls attention to the fact (in Part 7, inter alia), that there is no resemblance at all between the works of Nature and those of an Art which proceeds according to a design. (Arthur Schopenhauer - ON THE WILL IN NATURE)
Anthony Kenny makes it clear that Aquinas isn't that far from Paley:
Elsewhere, Aquinas says things which bring the Fifth Way nearer to the traditional argument from design. He produces more familiar examples of teleology in nature, many of them borrowed from Aristotle. The leaves in plants are arranged to protect the fruit; the foot is made by nature apt for walking; front teeth are good for biting, back teeth are good for chewing (ScG III, 3; In Physics II, 12 252). As examples of instinctive activities of brutes, he mentions the swallow’s building of its nest and the spider’s weaving of its web (In Physics II, 13 259). (Kenny, Anthony - The Five Ways)
And Kenny continues:
We should at this point make a distinction between two kinds of teleology: purpose and design. Design differs from purpose because design is purpose preceded by an idea: a thought, or blueprint, in somebody’s mind. If the world is designed, then there was a precedent idea in the mind of the creator – what, in the John’s gospel, is called the Logos or Word. Aristotle did not believe that the world was created; for him teleology was a basic fact about the cosmos, and no extracosmic designer was needed to explain it. It was Aquinas who formulated the argument from purpose to design. Things without awareness, he argued in the Fifth of his Five Ways, do not tend towards a goal unless directed by something with awareness and intelligence, in the way that an arrow is aimed by an archer. (ANTHONY KENNY – We have all been here before)
And again:
It is impossible, [Feser] says, “for a thing to be directed towards an end unless that end exists in an intellect which directs the thing in question towards it”. But what reason is there to accept this thesis rather than Aristotle’s claim that teleology, where it exists, is a basic feature of the universe? Feser’s argument is that what does not yet actually exist (for example, a house) cannot bring about an effect unless it already exists somewhere, and the only place in which it can exist is in someone’s intellect (for example, the architect’s). But surely this is to treat final causes as if they were efficient causes: for it is only of such causes that it is true that an effect cannot precede its cause. (ANTHONY KENNY – We have all been here before)
And one last time:
On the other hand, if even regular adaptive behaviour calls for intelligence, Aquinas has given us no reason why we should not call the swallows and the spiders intelligent themselves, rather than looking for an intelligence to direct them from outside the universe. (Kenny, Anthony - Five Ways)
A Schopenhauer quotation can serve as a supplement:
The physico-theological [teleological] thought, that Nature must have been regulated and fashioned by an intellect, however well it may suit the untutored mind, is nevertheless fundamentally wrong. For the intellect is only known to us in animal nature, consequently as an absolutely secondary and subordinate principle in the world, a product of the latest origin; it can never therefore have been the condition of the existence of that world. Nor can a mundus intelligibilis precede a mundus sensibilis; since it receives its material from the latter alone. It is not an intellect which has brought forth Nature; it is, on the contrary, Nature which has brought forth the intellect. […] Besides, the Physico-theological Proof may be simply invalidated by the empirical observation, that works produced by animal instinct, such as the spider’s web, the bee’s honeycomb and its cells, the white ant’s constructions, etc., are throughout constituted as if they were the result of an intentional conception, of a wide-reaching providence and of rational deliberation; whereas they are evidently the work of a blind impulse, i.e. of a will not guided by knowledge. (Schopenhauer, Arthur - ON THE WILL IN NATURE)
Feser complains that the intellectual world has banned teleological thinking since Descartes. But that is not entirely true from a philosophical-historical point of view. In the history of philosophy, there were many teleology-like concepts since Descartes (although they did not refer to the Catholic God). This is especially the case in the effective and worldwide influential German philosophy (Leibniz, the young Kant, Hegel, Schelling, Trendelenburg, Schopenhauer, the Schopenhauer school, and many others). The neglect of teleology-like thoughts can definitely not be blamed on the development of philosophy since modern times.

For me, the notion of teleology (applied to things of the world) basically only generates "a stimulating question", and rarely provides a "satisfactory answer" (Fritz Mauthner - Aristotle). In my first blog entry which is about natural law, there are further critical remarks on the aspect of teleology in the section Problematic Aristotelian teleology.

Feser's weakest arguments can be found in the chapter titled Universal acid. I expected much more from Feser. But so little came. The mere assumption of final and formal causes (which plants also have) should solve the profound problem of free will in no time at all. That is silly. Feser devotes very few pages to this topic, although it is the most important and central theme of philosophy. For if there is no free will, there is no morality that is strictly understood in an absolute or non-relative sense. But any kind of essentialism (even Aristotelian) excludes freedom of the will (in principle) unless further proof is given. Unfortunately, this is inevitable. Each essence (like that of the individual human being or that of its parts) can only act according to itself as an essence, it cannot break through itself (character, personality, and intelligence of the human being, or the definite features of its faculties) without breaking apart. A true arbitrariness or freedom that somehow acts independently or outside of one's own being (nature) like a divine effect (grace) or a quantum event is not plausible. It would not be a freedom that leads to responsibility according to our understanding, it would be externally determined, not self-determined. Nor would true freedom, which appears as an inseparable unity with one's essence, be plausible either. This would be illogical. I cannot be a very specific being that has a very specific finality (exclusively ordered to God according to Feser) and at the same time be/have an incomprehensible indeterminate being that is completely indifferent to all possible finalities. Even the deterministic Thomistic conception that no potential (like all kinds of potential human actions) can realize itself and thus requires something else from outside from which it is realized (circumstances that trigger those actions) makes it difficult to rationally grasp the freedom of the will. In the end, one must, for better or for worse, be content with a purely fideistic assumption of freedom of the will (if one wants to accept it at all; from a rational standpoint, it makes no sense).

I completely agree with the German philosopher F. H. Jacobi, who argues that
the belief in human freedom is incompatible with the view of reality that reason seems to require us to accept. Jacobi's claim is not merely that the belief in our own freedom cannot be rationally justified; he holds that any thoroughly consistent, rational understanding of the world will be committed to ruling out this very possibility. We are forced, then, on Jacobi's view, to choose between an irrational faith in the possibility of freedom and a rational but completely deterministic view of the world in which there is no room for self-determined agency. (Frederick Neuhouser – Fichte's Theory of Subjectivity)
Essentialism and the principle of sufficient reason completely exclude free will for me. I don't even want to go into Christian-theological ideas like divine providence, predestination, or original sin. Therefore I present only a few Bible quotations on the subject of the unfreedom of the will:
Jeremia 10,23: I know, O Lord, that the way of man is not in himself, that it is not in man who walks to direct his steps. 
Romans 9, 15: For he says to Moses, I will have mercy on whom I have mercy, and I will have compassion on whom I have compassion. 
Romans 9, 16: So then it depends not on human will or exertion, but on God, who has mercy. 
Romans 9, 18: So then he has mercy on whomever he wills, and he hardens whomever he wills.
Edward Feser can only act like Edward Feser, who exists as a unique person, who has the essence of man and of his very specific qualities. Edward Feser will always act necessarily on the basis of his current nature and knowledge. It is always Edward Feser who thinks, chooses, decides, and wants and acts, but always out of his (very specific) nature and always in a very specific situation which necessarily triggers his (then unavoidable) actions.

Now follows a series of quotations that should make clear why freedom of will is actually impossible:
The concept of a moral freedom, on the other hand, is inseparable from that of originality. For that a being is the work of another, yet in his willing and doing is supposed to be free, can be formulated in words but cannot be achieved in thoughts. After all, the one who called him into existence out of nothing has in the same way co-created and determined his essence as well, i.e., all his qualities. For one can never create without creating a something, i.e., a precisely determined essence in every sense and in all its qualities. However, later all its expressions and effects flow with necessity from these same determined qualities, in that they are only the qualities themselves brought into play, which merely required an external occasion in order to appear. How a human being is determines how he must act; therefore blame and merit do not adhere to his individual deeds, but to his essence and being. For this reason theism and the moral responsibility of the human being are incompatible, precisely because responsibility always falls back on the author of the being, where it has its centre of gravity. People have sought in vain to bridge these two incompatible concepts, but the bridge always collapses. The free being must also be the original being. If our will is free, then it is also the original being and vice versa. (Schopenhauer - Parerga and Paralipomena: Volume 2 translated Christopher Janaway)
On the other hand, theism in regard to the past is also in conflict with morality, because it abolishes freedom and accountability. For neither guilt nor merit can be conceived in a being that, in regard to its existence and essence, is the work of another. Already Vauvenargues says very correctly: ‘A being that has received everything can act only according to what has been given to it; and all the divine power that is infinite could not make it independent.’ For, as any other conceivable being, it cannot act except in accordance with its constitution and thereby make the latter known; but it is created here the way it is constituted. If it acts badly, that is a result of its being bad, and then the guilt does not belong to it but to him who made it. It is inevitable that the author of its existence and its constitution, as well as the circumstances in which it has been placed, is also the author of its actions and its deeds, which are determined by all this with such certainty as a triangle by two angles and a line. St Augustine, Hume, and Kant have clearly seen and understood the correctness of this reasoning, while others have ignored it in shrewd and cowardly fashion[.] (Schopenhauer - Parerga and Paralipomena: Volume 2 translated and edited by Adrian Del Caro and Christopher Janaway)
Everything that is also is something, has an essence, a constitution, a character; it must be active, must act (which means to be active according to motives) when the external occasions arise that call forth its individual manifestations. The source of its existence is also the source of its What, its constitution, its essence, since both differ conceptually, but in reality cannot be separated. However, what has an essence, that is, a nature, a character, a constitution, can only be active in accordance with it and not in any other way; merely the point in time and the particular form and constitution of the individual actions are each time determined by the occurring motives. That the creator created human beings free implies an impossibility, namely that he endowed them with an existence without essence, thus had given them existence merely in the abstract by leaving it up to them what they wanted to exist as. On this point I ask the reader to consult §20 of my treatise On the Basis of Morals. – Moral freedom and responsibility, or accountability, absolutely presuppose aseity. Actions will always result with necessity from character, that is, from the specific and thus unalterable constitution of a being under the influence and in accordance with motives; therefore, if the being is to be responsible, it must exist originally and by virtue of its own absolute power; it must, in regard to its existence and essence, be its own doing and the author of itself if it is to be the true author of its deeds. (Schopenhauer - Parerga and Paralipomena: Volume 2 translated and edited by Adrian Del Caro and Christopher Janaway)
It would now seem that man has the liberum arbitrium indifferentiae, i.e. that his will is free because, as we have seen, he can carry out deeds which are not at all in accordance with his character, but rather completely contrary to his nature. But this is not the case: the will is never free and everything in the world happens with necessity. Every human being has a certain character at the time when a motive approaches him, who, if the motive is sufficient, must act. The motive occurs with necessity (because each motive is always the link of a causal series dominated by necessity), and the character must follow it with necessity, because it is a certain one and the motive is sufficient. Now I set the case: the motive is sufficient for my character, but insufficient for my whole self, because my mind sets up my general well-being, as counter-motive, and this is stronger than that. Have I now acted freely because I did not yield to a motive sufficient for my character? In no way! Because my mind is by nature a certain one and its education, in any direction, happened with necessity, because I belong to this family, was born in this city, had these teachers, cultivated this contact, made these certain experiences, etc. That this mind, which has become necessary, can give me, in the moment of temptation, a counter-motive that is stronger than all the others, does not break necessity at all. Also, the cat acts against its character, under the influence of a counter motive, if it doesn’t nibble in the presence of the female cook, and yet nobody has yet granted free will to an animal. I further suggest already now that the will can be brought so far, through the realization of its true well-being, that it denies its innermost core and no longer wants life, i.e. it puts itself in complete contradiction with itself. But when he does this, does he act freely? No! For then the knowledge has merged into him with necessity and with necessity he must follow it. He cannot do otherwise, as little as the water can flow uphill. If we do therefore see a man not acting according to his known character, we are nevertheless faced with an act which had to occur just as necessarily as that of another man who only followed his inclination; for in the former case it arose from a certain will and a certain mind capable of deliberation, both of which worked together with necessity. To infer from the deliberative capacity of the mind the freedom of the will is the greatest fallacy that can be made. In the world we only ever have to deal with necessary movements of the individual will, be they simple or resulting movements. It is not because the will in man is connected with a spirit capable of deliberation that he is free, but because of this reason he has a different movement than the animal. And this is also the focus of the entire investigation. The plant has a different movement than a gas or a liquid or a solid, the animal a different movement than the plant, the human being a different movement than the animal. The latter is the case because in man the onesided reason has developed into a perfect one. Through this new tool, born of the will, man overlooks the past and looks to the future: now, in any given case, his well-being, in general, can move him to renounce enjoyment or to endure suffering, i.e. to force him to do deeds which are not in accordance with his will. The will has not become free, but it has made an extraordinarily great gain: it has attained a new movement, a movement whose great significance we shall fully recognize below. Man is never free, then, whether or not he has within himself a principle which can enable him to act against his character; for this principle has become with necessity, belongs with necessity to his being, since it is a part of the movement inherent in him, and acts with necessity. (Philipp Mainländer)
A. What do you understand by the liberty of indifference? B. I understand spitting on the right or the left hand — sleeping on the right or left side — walking up and down four times or five. A. That would be a pleasant liberty, truly! God would have made you a fine present, much to boast of, certainly! What use to you would be a power which could only be exercised on such futile occasions? But in truth it is ridiculous to suppose the will of willing to spit on the right or left. Not only is the will of willing absurd, but it is certain that several little circumstances determine these acts which you call indifferent. You are no more free in these acts than in others. Yet you are free at all times, and in all places, when you can do what you wish to do. B. I suspect that you are right. I will think upon it. (Voltaire) 
But what! the other animals will have the same liberty, then, the same power? Why not? They have senses, memory, feeling, perceptions, as we have. They act with spontaneity as we act. They must have also, as we have, the power of acting by virtue of their perceptions, by virtue of the play of their organs. (Voltaire) 
The Thomist wants to avoid a determinism of circumstances so that the only form of external determination compatible with free action is that which comes from God (but there is no action without the influence of mundane external circumstances)There is no way around it, the Thomists must be compatibilists with regard to divine concurrentism (which, by the way, entails the middle ground fallacy):
For example, Thomas Flint is not alone in having difficulty in finding a neat category for Thomist approaches to freedom. Flint concedes that Thomists rarely style themselves as compatibilists, in that they reject a ‘determinism of circumstances’. This would fit with Stump’s characterization of Aquinas’s position that ‘a decision is free only if it is not the outcome of a causal chain that originates in a cause outside the agent’. Nonetheless, Flint complains that ‘the kind of divine activity that the Thomists see as compatible with human freedom would not be deemed compatible by those with libertarian inclinations’:
For the heart and soul of libertarianism is the conviction that what an agent does freely is genuinely up to the agent to do freely or refrain from doing freely; no external circumstance, no other agent, does or even can determine what I do freely. Physical determinism, which sees my actions as determined by physical laws and prior states of the universe, is clearly at odds with this core insight. But surely the Thomist picture of simultaneous divine determinism [Flint’s description of concurrentism] will strike the true libertarian as equally destructive of human freedom. And, indeed, if external determination is incompatible with human freedom, does it really make that much difference how much the determination is accomplished? Are the movements of a hand puppet any more under its own control than those of a windup doll? In sum, if we think of compatibilism in the broader sense as the view that a free action can be externally determined, does it not appear that Thomism is indeed ultimately rooted in compatibilism? (CHRISTOPHER J. INSOLE: Kant and the Creation of Freedom – A Theological Problem)

Anthony Kenny also thinks that Thomists are compatibilists:

Aquinas’ account of the rooting of freedom in reason shows him to be a compatibilist, that is to say, a philosopher who sees no necessary contradiction between free choice and determinism. ‘Perhaps we too’, Pasnau says, ‘do not escape the chains of causal necessity. But if we are determined, we are determined by our own beliefs and values, not simply by the brute design of nature and the happenstance of events. This difference, for Aquinas, makes all the difference.’ (From Anthony Kenny's review of Robert Pasnau's "Thomas Aquinas on Human Nature".)
The actual problem of freedom generated by essentialism is ignored by the Thomist. The fact that God’s action on the creature when acting is supposed to be the source of the creature’s freedom seems completely silly to me. If one were to scrutinize the Thomists' theory of freedom thoroughly, one would see the silliness to the full. Because one would only see a mystery.

The freedom of the will could be lost if the mental of the human being must be considered as potentiality actualized by God. Because the most important terms for the freedom of the will are of a mental nature: insight into the action alternatives, deliberation, decision, intention.

When theists prove their God, there is always dishonesty. For in order to come to God, they proceed from preconditions that exclude freedom of will. But the preconditions are quickly forgotten as soon as God is established so that the way is cleared for blame and recriminations.

The true universal acid, the really dangerous idea, is that of evolution and not, as Feser assumes, that of final causality. If the theory of evolution is correct, at least in the organic world, there would be no fixed and static Aristotelian forms (what is meant are universal general forms and not nominalistic individual forms). A squirrel, for example, with all its abilities and qualities, would be a product of mercilessly brutal natural selection. And every generation of squirrels could undergo a small or large change over time, which in turn would then have an impact on the next generation. Change would be an integral part of the generational transition, and thus part of the essence of the squirrels. The same would apply to man so that there can no longer be an absolute form of man which supposedly does not include homosexuality. Evolution concerns not only the outer form of a living being (only this seems to be what Feser has in mind regarding natural law, whereby he also only sees what he wants to see) but also its behaviors and inner dispositions and tendencies (evolutionary psychology deals with this topic with humans). All that needs to be included in the evaluation of biological functionalities if one wishes to take part in the game of a certain natural law (such as that of Feser). Additionally, functions are the outcome of natural processes, such as selection, and not of the fulfillment of any intentions of an external (divine) agency. There is a lot to say about natural law. I did that in my first blog entry ( As a side note, and speculatively, if humans could create a conscious organic robot with different weird functionalities, then this robot would hardly be morally obligated (to us or to itself or even to a god) to respect these functionalities.

I have come to the conclusion, and there is no doubt in my mind, that Thomistic natural law is not only dependent on a belief in God or believing in the validity of a proof of the same, but above all that it is dependent on a belief in the Catholic Church and its teachings and in the fact that these teachings have been "dictated", so to speak, by the Holy Spirit. Without such belief, natural law hangs in the air as an indeterminate, indefinable theoretical something. For the speechless, silent and dumb nature I can interpret in many ways; and that it addresses to me a moral ought, is something the church has to tell me. Natural law is thus not only theologically but also denominationally bound. Therefore, it is not convincing in purely philosophical terms.

Nevertheless, I will present here some new thoughts and quotations. Basically, we owe the natural law mess to Plato and his theory of ideas. That's where the (elitist) subjectivism disguised as objectivism really gets going. The core problem seems to me to be that nobody really understands what exactly is meant by natural law. Without the idea of a legislator (deity) the whole concept makes little or no sense in my opinion. And since, in order to understand laws, we should of course also know something about the legislator and his intentions. But do we really know anything about these matters? I don't think so. Even those who agree in principle to natural law are often unable to agree on important details. Among Catholic moral thinkers, there is also no consensus on the justification of natural law. There are many (like Germain Grisez, John Finnis, Robert P. George, Shalina Stilley, and a lot more) who reject the arguments advocated by Feser, and Feser with others rejects theirs (so there are competing Thomistic Natural Law versions). We assume that both parties are right in their criticism because they are both well trained in the scholastic technique of argumentation so that the natural law of the Thomists already dissolves from within. 

And if even the supposed paradigm of unshakable knowledge, namely mathematics, cannot be safe from error, then why should we believe in the fundamental unshakability of the basic moral assumptions of Thomistic natural law (the natural law scholars are known to always make an analogy to mathematics)?

Henry Sidgwick delivers a good critique of natural law ethics (at least the naturalistic aspect of it)
If for example we want to get practical guidance from the conception of human nature regarded as a system of impulses and dispositions, we must obviously give a special precision to the meaning of ‘natural’. Why? Because every impulse is ‘natural’ in a sense (Butler’s point), and there’s no guidance for us in this: the question of duty is never raised except when we want to know which of two conflicting impulses we ought to follow. ‘The supremacy of reason is natural’—it’s no use saying that, because we have started by assuming that reason tells us to follow nature, so that our line of thought would become circular—Nature points to Reason, which points to Nature. The Nature that we are to follow must be distinguished from our practical reason, if it’s to become a guide to it. Then how can we distinguish the ‘natural impulses’ that are to guide rational choice from the unnatural ones? The friends of the natural seem usually to have interpreted ‘natural’ to mean either common as opposed to the rare and exceptional, or original as opposed to what develops later, or not an effect of human volition as opposed to the artificial. But I have never seen any basis for the view that nature abhors the exceptional, or prefers the earlier in time to the later; and looking back over human history we find that some admired impulses—e.g. the love of knowledge, enthusiastic philanthropy—are both rarer and later in their appearance than others that all judge to be lower. And tying ‘natural’ to the natural processes of our bodies the prescription ‘follow nature’ will give us very little guidance, because almost always the practical question is not whether we are to use our organs or leave them unused but how we are to use them. . . . Summing up: I don’t think that any definition of natural shows this notion to be capable of providing an independent ethical first principle. (Henry Sidgwick - The Methods of Ethics)
Here is a compact critique by Kai Nielsen:  
I shall limit myself here to four general criticisms of the Thomistic conception of the natural moral law.
1. We are told that natural moral laws are self-evident, absolute, rational laws. They are certain and can be known without any doubt at all to be true. This sounds very reassuring for it promises to give us the kind of objective knowledge of good and evil that we very much desire. But there is here no genuine surcease from our perplexities about an objective justification of moral beliefs. It would be a mistake to believe that advocates of natural law are claiming that honest, nonevasive, intelligent reflection will necessarily make it clear to impartial and informed examiners that there are natural moral laws and that the laws generally claimed to be natural laws are indeed natural laws. Since the natural laws are only self-evident in themselves and not necessarily self-evident to us, what could it mean to say that they are certain and that we can justifiably claim to be certain of them? For such a certain knowledge of good and evil, we require moral principles that can be seen to be self-evident to us or natural moral laws of whose truths we can be certain. But since natural moral laws are only self-evident in themselves (assuming we know what that means) and since it is God's reason and not man's that is the source of the moral law, we poor mortals can have no rational certitude that the precepts claimed to be natural laws are really natural laws. Beyond this it is surely a mistake to claim that laws or anything else are self-evident in themselves, where it is impossible to know or have grounds for asserting that they are self-evident. If a law or proposition P is such that we could never, even in principle, be in a position to justifiably claim that it either is or is not self-evident, since we mortals have and can have no grounds for claiming that it is self-evident, then it is senseless to assert or deny that P is self-evident in itself. If human beings can have no grounds for asserting that something is self-evident, they can have no grounds at all for asserting it is selfevident in itself. "What we don't know we don't know" is a significant tautology.
2. We find out what man ought to be, natural theorists claim, by finding out what are the specific rational ways in which he is to conform to the Eternal Law, by finding out what man is, by discovering man's essential nature. (They claim these things come to the same thing.) As one natural law moralist put it, "Morality is man's knowledge that he ought to become what he is; that he ought to become a man by conduct becoming to a man." In order to know how men should live and die we must understand man's essential nature. But to this it can be objected that from the point of view of science man has no essential human nature. Men are not artifacts with an assigned function. It is both linguistically odd and cosmologically question-begging to ask what men are for—assuming by this very question that they are Divine artifacts rather than persons in their own right. Science does not ask what men are for; it does not know how to inquire or even what it is to inquire into man's essential nature, where this is something human beings must achieve or hold in order to become or remain genuinely human. Science has no such conception. For the Thomist to speak of man's essential nature requires the background assumption that a human being is a creature of God. But that human beings are creatures of God is not part of the corpus of any science. In fact it is a completely unverifiable statement whose very factual intelligibility is seriously in question. But unless we can establish the factual significance of such an utterance we have no grounds at all for saying man has, in the requisite sense, an essential nature. If we have no grounds for saying man has an essential nature then we have no grounds for claiming there are natural moral laws. (In refusing to speak in such a manner, of "the essential nature of man," we are not denying that it may be discovered that there are certain characteristics that all men and only men as a matter of fact have, but these empirically discoverable properties—if such there are - do not prove or in any way establish that there is something a man must have in order properly to be called a man. It does not establish or even suggest that there is something man was made to be.)
3. The first principle of the natural moral law is a tautology (if you will, a truism) and is thus not a substantive moral proposition. It is compatible with a completely relativistic view of morals, for it does not tell us what is good or what is evil but it only makes explicit what is already implicit in the use of the words "good" an "evil," namely, that if something is good it is, everything else being equal, to be sought and if it is evil it is, everything else being equal, to be avoided. But it does not and cannot tell us what is to be sought and what is to be avoided. To discover this we must turn to the substantive secondary precepts of the natural moral law. But some of these run afoul of the facts concerning moral relativity, for some of them are not always even assented to, much less are they always accepted as self-evident by all people. If we say (as Aquinas does) that all people whose natural inclinations are not "corrupted by vicious habits" and "darkened by passions and habits of sin" acknowledge these natural laws, we can ask, in turn, where do we get our criteria for deciding whose habits are vicious and sinful and whose are not? To rule out some natural inclinations as corrupt or sinful indicates that we are using a criterion in moral appraisal that is distinct from the natural law criterion of basing man's moral conceptions on his natural inclinations. What actually happens is that those moral beliefs that are incompatible with Catholic doctrine, and as a result are called corrupt and sinful, are simply arbitrarily labelled as "unnatural" and "abnormal." (I will illustrate this in a moment.) But to do this is not to base morality squarely on natural law conceptions. We have here the application of moral criteria that in reality are not based on natural law conceptions. Without such an application—an application drawn from religious doctrine and not from what we learn about human nature or from what we can derive from the first principle of the natural law—natural law conceptions could not overcome the moral relativity they were designed to transcend. (Indeed, they do not anyway, for the tacit appeal to Church doctrine is surely an appeal to something that is culturally relative.) If in defense of such natural law conceptions, it is replied: "We do not claim that all people and all cultures always acknowledge these laws, but the crucial thing is that most of them do," we make another egregious error, for, if we argue in this way, we have now presupposed that moral issues can be settled by statistics or by some cross-cultural Gallup Poll. But Aquinas would surely not wish to say that moral issues are "vote issues." As Father Daly puts it, "Catholic moralists... do not equate moral right with statistical averages." To argue that what most people value is valuable is to assume rather simple democratic standards and by assuming them we again have a standard that is (a) not self-evident and (b) independent of the natural law. To avoid ethical relativism the natural law theorist must incorporate into his theory moral conceptions that are not based on the natural moral law and are questionable in their own right.
4. Natural moral law theorists confuse talking about what is the case with talking about what ought to be the case. They confuse dejure statements with de facto statements. A statement about what people or what normal people seek, strive for or desire is a factual, non-normative statement. From this statement or from any conjunction of such statements alone no normative (de jure) conclusions can be validly deduced except in such trivial cases as from "He wears black shoes" one can deduce "He wears black shoes or he ought to be a priest." But this simply follows from the conventions governing the disjunction "or." Moreover, because it is a disjunction it is not actually actionguiding; it is not actually normative. To discover what our natural inclinations are is simply to discover a fact about ourselves; to discover what purposes we have is simply to discover another fact about ourselves, but that we ought to have these inclinations or purposes or that it is desirable that we have them does not follow from statements asserting that people have such and such inclinations or purposes. These statements can very well be true but no moral or normative conclusions follow from them.
(Kai Nielsen - Atheism and Philosophy)
As for the rest, I will follow what A. C. Grayling has to say:
Sober reflection suggests that if sex were allowed a more natural place in human life it would take up far less time and make far less trouble than it currently does. Even in the more relaxed and mature societies of the world attitudes to sex and sexuality consume too much social oxygen, with the result that unnecessary harm is caused.
Nature has made sex pleasurable not just to ensure reproduction but, in some of the higher mammals at least, to create bonds. The narrow views of the ancient Jews and the modern Catholics, that sex must always have pregnancy as a possible outcome, miss a very important point here. The closest relatives to humans are bonobo chimpanzees, which engage in sex almost as a greeting, casually and often. Unlike them and humans, sexual activity among other mammals is governed by the oestrus cycle, which makes females interested only when ready for pregnancy. As far as anyone can tell, other animals do not spend much time agonising over sex: they get on with it when nature and opportunity provide the prompt.
Human sex is more complicated, of course, because of the tangled social fabric surrounding it. Before effective contraception it was potentially a huge investment for a woman to have sex, and the biologists are keen to point out the additional evolutionary reasons that make men naturally more promiscuous than women. Just how promiscuous men might be if given the chance is perhaps illustrated by certain kinds of male homosexual activity of the ‘cottaging’ variety, involving frequent promiscuous encounters without much or any emotional attachment. The thought is that heterosexual men might behave as their homosexual brothers do if they did not face the restraints imposed by potential female partners.
It is now recognised that effective contraception and greater economic independence have together wrought significant changes in attitudes to sex among women. Moralists decry the increased sexual freedom that results, and point to accompanying increases in sexually transmitted diseases, and greater instability in partnerships and marriages, as the penalties being paid. But on the other hand it might be said that less frustrated and more experienced grown-ups make better choices about long-term relationships eventually, and that anyway pleasure is a good – and sexual pleasure a great good – providing it is responsibly done: and if responsibly done, it is hard to see the objection.
As this suggests, sex is not an ethically neutral activity. On the contrary, it carries a high ethical value, which is that when it is consensual and responsible, and governed by the principle that those engaging in it must not do harm, it is a deeply valuable thing. How can it not be, when it can so well bring people together in intimacy and delight?
It is an oddity that our culture should be so vehemently anti-gay given our simultaneously held view of classical Greece, which we admire and claim as our cultural ancestor. The Greeks not merely permitted but encouraged homosexuality, and not merely homosexuality but pederasty, which in addition to its romantic and sexual aspects was intended as a form of male socialisation in which older men trained boys in the ways of the polis and the duties attendant on membership of it.
The latter is a custom many will think well superseded, and for good reason. But we allow other and even worse things to persist to this day: the genital mutilation of millions of boys and girls in religious practices of circumcision. The standard case against homosexuality is that it is ‘unnatural’ because (say its opponents) the way male and female sex organs are constructed and arranged ‘shows’ that sex should only take place between men and women. If something’s being unnatural were enough to outlaw it, circumcision would be outlawed. In fact circumcision is vastly more unnatural than homosexuality, which is observed in quite a few species in nature. Likewise opponents of gay sexual life say that the male body is not ‘for’ receiving the sexual attentions of another male. If this ‘for’ argument carried weight, then since human legs are not ‘for’ riding bicycles, bicycles and the riding of them should be outlawed.
These points demonstrate that invocations of ‘nature’ provide no ground for opposing homosexuality. The real source of opposition is religious, and religious opposition succeeded in institutionalising social and legal sanctions.
(A. C. Grayling - The God argument)
Feser's version of Thomistic natural law operates with the terms "in contrary to" and "other than". For systematic reasons, the term "in accordance with" should also be added.

That is, to act contrary to the nature of one of my parts is morally evil, to act in accordance with it is morally good, and, to act other than it is morally neutral.

If I eat breakfast and clean myself in the morning, that is already morally good, because I am acting in accordance with my nature. Natural law does not make it difficult for me to be good in this case. If, among other things, the mouth and tongue are naturally there for smooching or French kissing, then moral pluses can also be obtained quite easily during this sensual activity.

In contrast, it would be morally evil, as it would be contrary to nature, if a man had to give a sperm sample for cancer diagnosis and the sample was done by means of masturbation. Equally morally evil would be a spermiogram, which provides a reliable indication of sperm quality when infertility is suspected, if the semen sample was again obtained through masturbation.

Chewing gum would be a case of moral neutrality. This is because my food intake system is merely used differently than in the normal eating process. Although the chewing of a nutrientless gum cheats my stomach, which expects real food, although my chewing movement runs into emptiness and therefore my masticatory muscles are unnecessarily strained, although something not to be chewed and digested would have to be spat out immediately and should not be kept in the mouth deliberately, although I may have the provocative attitude and intention to demonstratively pervert my food intake system while chewing, chewing gum is in itself morally neutral.

However, nobody has really been able to understand Feser's distinction between "in contrary to" and "other than". In both cases the natural end is deliberately not aimed at (instead, a different, new, "unnatural" end is sought), and yet only in the case of "in contrary to" somehow something evil comes along.

Even an intellectual companion of Feser, who follows the same moral line, i.e. argues very similarly, cannot do anything with Feser's distinction:
Feser relies upon an unclear account of contrary use and other than use, which is either ad hoc or cannot grant him the conclusion he desires. (John Skalko – Disordered actions)
If the distinction is untenable, Feser's version of natural law fails miserably. For then either trivial acts such as chewing gum, walking on one's hands, propping up a broken table with one's legs would be morally bad, or all acts previously classified as evil would be morally neutral.

After all, John Skalko is someone who also comes up with the argument of the perverted faculty. Faculty here is to be understood as the power or ability to do something. On the other hand, there are many conservative Catholics who have no use for the argument in question. Among them is the Catholic moral philosopher Germain Grisez, who has studied Aquinas extensively and considers this argument weak.

The argument of the perverted faculty was developed by Thomists in the 19th century and was already controversially discussed among Catholic moral philosophers in the USA at the end of the 1920s:
In the articles mentioned in note 1 above, Davis defended the perverted· faculty argument, Mahoney and Ryan did not consider it sufficient by itself although they did not reject it, while Cooper criticized it very effectively. (Grisez – Contraception)
Cooper's point of view is summarized here:
Cooper targeted the deductive “perverted faculty” argument by saying that Catholic authorities have offered “facile assumptions” in place of “objective evidence” as to “what precisely is the natural function of the faculty (sex) under consideration?” (Alexander Pavuk - Catholic Birth Control?)
And again from another source:
John Montgomery Cooper, Ryan´s colleague at the Catholic University, was himself not wholly persuaded by the natural law argument, at least as a proof that contraception was mortally sinful. „Just precisely how are we going to formulate such a definition of the natural function of the reproductive faculty as will permit relations in pregnancy and sterility and yet bar contraceptive practices?“ he wanted to know. „And after we have succeeded – if we succeed – in so formulating this function, just precisely what concrete objective evidence are we going to muster to show that our formulation, and no other, represents the true function?“ (Leslie Woodcock Tentler - From Catholics and Contraception. An American History)
At least it can be said that at that time two out of four Catholic philosophers considered the argument insufficient in itself. So one may have to add something like a certain but changeable and unstable feeling of shame or disgust and a (purely Catholic) intuition that cannot be further substantiated.

Nonetheless, three out of four Catholics who were in the intra-Catholic debate had a problem with the argument in some way. So how were secularists to be convinced?

Even a recent study by a Catholic philosopher finds the New Natural Law of someone like Grisez more convincing than the classical Aristotelian-Thomistic one:
The overarching thesis of this dissertation is that—although each solution is in some way problematic—the solution of new natural law theorists is the least problematic if one wishes to implement an ―ought that is moral, prescriptive, non- relativistic, determinate, and related to the common good. (Shalina Stilley - NATURAL LAW THEORY AND THE IS- OUGHT PROBLEM: A CRITIQUE OF FOUR SOLUTIONS)
Why does Grisez find the perverted faculty argument unconvincing? He says that the premise involved in the argument is untenable. And he even says this:
The many attempts over the years to show the intrinsic immorality of contraception using this faulty premise have exposed Catholic moral thought to endless ridicule and surely have caused harm in other ways. (Grisez – Contraception)
Grisez gives many illustrative counter-examples as arguments, one of which is quoted below.

One can cite another possible example, not mentioned by Grisez himself, but which comes up again and again in discussions on natural law. And it is one that concerns human hair.

For sure, hair that grows densely and concentrated on certain parts of the body and is longer than the down on the whole body has a final cause. This consists of either a protective or signaling function, or both. When I speak of hair, I always mean a sum of individual hairs that have their fixed place on the body, such as armpit hair, pubic hair, or head hair and so on, and that in a sense perform their function as a collective unit. Now comes the natural law crux. Shaving the aforementioned hair areas thoroughly, however, would temporarily nullify the exercise of their function, which is automatic and permanent. Thus, a trivial act like shaving would be morally bad because it is done against the telos of nature. It completely suspends for a short time the final cause that aims at permanent actuation. In other words, it is not the growth of the hair that is perverted, but the faculty or power that the hair unfolds as a collective whole. That the hair on the head of man has a protective function can be proved by the authority of Aristotle, who for the Thomists is one of the greatest philosophers of nature:
Man has the hairiest head of all the animals. First, this is necessarily so because of the fluidity of his brain and the sutures in his skull. For there must necessarily be the largest outgrowth where there is most fluid and heat. Secondly, it is for giving protection, so that the hair may give shelter and protection from excesses of cold and heat. The human brain, being the biggest and the most fluid of all, needs the greatest amount of protection, since the more fluid a thing is the more liable is it to excessive heating or chilling. (Parts of Animals II.14.658b2)
The same applies to eyebrows and eyelashes:
Both eyebrows and eyelashes exist for the protection of the eyes. The eyebrows, like the eaves of a house, give protection from the fluids running down from the head; the eyelashes, like the palisades sometimes put up in front of an enclosure, are there to keep out things that might get in. The eyebrows are at the junction of two bones -- which is why they often get so thick in old age that they have to be cut. The eyelashes are at the ends of small blood-vessels. For these vessels come to an end where the skin itself terminates. At these places the moisture that comes off, being corporeal, must necessarily cause the formation of hairs, unless it is diverted by nature to some other use. (Parts of Animals II.15.658b14)
Grisez's New Natural Law bases its argumentation less on bodily functions or used body parts than on abstract categories that are understood as goods and that contain the true ethical telos. Grisez can also draw on Aquinas for this version of natural law.

Instead of arguing from the concrete, it starts from the general, as with the Christian good of marriage, in which it is said to be inevitably and naturally directed toward founding a family.

If we now consider the statements of Skalko and Grisez, the Thomistic program of natural law seems to hang somehow in the air.

The following example from Grisez, who uses it to invalidate the argument of the perverted faculty:
Imagine a person who ingests some food and drink by mouth for satisfaction although for medical reasons the stomach constantly is pumped so that nothing is digested. Real nourishment is given intravenously. Would any moralist object if such action seemed medically harmless and was comforting to a very ill patient? (Germain Grisez - Contraception and the New Natural Law)
At first glance, Feser also seems to consider the example morally unobjectionable:
Feser is saying that the perverted faculty argument does not apply to the example. (
The blogger Angra Mainyu creates in the comment section a sexual analogue for it:
In Grisez's example, the person eats the food only for pleasure, knowing that it will be removed for medical reasons, and agrees to that removal. The fact that keeping the food in the stomach would be dangerous for him does not help the person escape condemnation by the perverted faculty argument. Here, a relevant analogy would be as follows:
Alice and Bob agree to have sex. They know that allowing the reproductive process to continue would be dangerous for medical reasons and plan to stop it by taking a contraceptive pill after sex (or removing the semen and killing any remaining sperm cells before there can be any fertilization, or another such method), and then they do as planned. There is no difference in terms of risk. Also, they are both cases of "an individual deliberate act of using a bodily faculty" rather than "an ongoing and involuntary physiological process", and the natural end is frustrated (I would call it the main function, but that aside). There is no relevant difference here, so the perverted faculty argument would condemn the person eating food in that context, just as it would condemn the actions of Alice and Bob. (
Some Thomists would mention shame in the sexual variant as an important criterion for recognizing moral relevance. But shame is a poor criterion. Even dogs seem to feel shame when they defecate, if they receive a lot of attention from humans while doing so. Buying toilet paper can be associated with shame. The same is true for a visit to the sauna. The ancient Romans used to have much less shame in things that we are very ashamed of today. There are certainly countless other examples that could be cited. The sense of shame is certainly in flux and therefore not a good criterion for moral differentiation.

Feser, on the other hand, would probably just come up with his "contrary to" and " other than" distinction, appealing a bit to intuition along the way, but with manipulative vigor and seriousness. But in this case, that distinction would really be ad hoc.

The Catholic Church will make a very different argument that can be discovered when it speaks of protected sex:
As Humanae vitae has made clear, the true disorder in a contraceptive act is not "frustration of nature" but disruption of the symbolic nexus of love and fertility.

If some action is condemned, it is not because it violates animal biology, but because it is contrary to something in the special relation of two persons united by marriage encountering each other in conjugal intercourse.
(John T. Noonan, Jr. - Contraception)
The offense of Alice and Bob, in the Catholic Church's estimation, is not that their biological nature is frustrated, but that something spiritual has obviously been violated, which seems to concern merely a particular matter of faith.

The strict natural law requirements regarding sexuality are strongly reminiscent of the work specifications in companies and businesses. These specifications are impossible to realize, and every employee can relate to this. But they have to exist for reasons of stability, so they are intended precisely because of their unattainability. After all, if the guidelines were shifted a little more into the loose, the employees' attitudes and ultimately their effectiveness would become a little looser, which would not be conducive to business and operational profitability as a whole. Missing targets is ultimately only superficially problematic, after all, and the top bosses and leaders know this, including Catholic scholars and officials.

Sexual moral transgressions fall under the mortal sin of luxuria. There are at least 6 other deadly sins. You can also eat and drink your way to hell like Catholic Bavarian men with their fat bellies. The Catholic Swabians in Germany go to hell because of their stingy money saving. The Protestant North Germans are lazing their way into hell. 

The observance of natural law could also be, in part, an abstract and transcendent remnant of magical thinking. In the past, certain religious rituals may have had procedures that had to be followed in strict order, and deviating from it would only have offended the gods or ancestors.

The superstitious aspect resonates here: 
It is impious, says the old Roman superstition, to divert rivers from their course, or invade the prerogatives of nature [Tacitus, Annals 1: 79]. (David Hume - On Suicide)
The focus of Thomistic natural law advocates on human sexuality is also somewhat odd. They may deny the focus over and over again, but when you hear them talk or read them, the subject of sexuality is ubiquitous and especially emotionally charged. Evolutionary psychology may have an explanation for this. For it attempts to give an evolutionary theoretical justification for the different moral systems of liberals and conservatives.

Here is an example of what an evolutionary psychologist has to say:
We reflect on a population of birds in which different individuals do better or worse, in terms of their fitness, depending on the rules surrounding mating that are imposed on them. In such birds, there could be selection for modules designed to impose these rules, even though they might well not know that this was the origin of their “moral intuitions” about behavior in the sexual realm. [...]

Organisms are better or worse off, in terms of reproductive success, depending on the rules of the mating game. Suppose that humans, like some of our primate relatives, are, potentially at least, somewhat polygynous, with the “best” males getting more than one mate, meaning some males will be left with none. Low-quality males would have a deep, abiding, even crucial interest in rules that force everyone into monogamy—in such a world, the low-quality males do a lot better. Similarly, some women are better off with enforced monogamy. This implies that—at least the possibility that—some modules are designed to try to impose certain sexual rules on other people. I think the way this works is through moral intuitions surrounding behavior like abortion, prostitution, and much else that might be associated with promiscuity or mating patterns. The key is that some people win and some people lose in the evolutionary sense under different regimes. I think this explains the large differences in views on sexual behavior. The issues surrounding sex and morality are, no doubt, going to turn out to be more complicated. My main purpose here has been to sketch what an argument might look like for explaining why people are inclined to constrain other people’s behavior. [...]

If a high-quality male could prevent some males from polygyny while simultaneously being polygynous himself - having one monogamous mate, and then having illicit but unpunished affairs - that would be the best of all possible worlds in terms of fitness.

To the extent that high-quality males can protect themselves from punishment for having extra-pair matings, the rule prohibiting them is less of a problem. Who stands to lose if monogamy is enforced? Single females do, since they’ll be forced to mate with the lower-quality males. Basically, they’ve lost all the advantages of having the choice described in the polygyny threshold model because they can no longer select a potentially better option, becoming the second female on a high-quality male’s patch. Suppose that selection acted on this bird species, and they came to be designed to favor the arrangement that benefited them, even if they couldn’t say why. In the same way that our birds might very much like to have sex without having to understand the relationship between sex and reproduction, they might have preferences for monogamy and polygyny in line with their reproductive interests without knowing the ultimate cause of these preferences. One can easily imagine what would happen if high-quality males got to make the rules, or, if there were some sort of democracy instituted, how these birds would vote.The point is that in a species in which individuals can constrain others’ behavior with rules, you’d expect evolution to act to cause members of the species to favor rules that serve their reproductive interests even if they don’t know this is why they’re endorsing these rules. [...]

It should be clear that any bird social scientists would have a serious problem trying to figure out the true cause of moral intuitions if their only tool was asking other birds to justify their moral stance. Without Darwin, of course, these bird scientists would be in trouble because they wouldn’t know how to think about what the modules designed to generate moral judgments were up to. [...]

Again, they probably wouldn’t know why they were opposed to these practices. They would be insensitive to arguments about freedom and individual choice. They would probably be “pro-family” and interested in “traditional values” and so on. Further, because they didn’t know why they wanted to constrain other birds’ sexual behavior, they would be forced into contradictory positions. They might be opposed to abortion —the availability of which, by reducing the costs of sex, might well be linked to promiscuity—and say that their opposition is based on the principle that a new life begins at conception, even though their intuition is really that a female bird who is promiscuous ought to be punished. These birds would be “pro-life,” “pro-family,” and other platitudes, but basically their minds would be designed to prevent other birds from having sex. [...]

From an evolutionary point of view, sex is fundamental, and if there were going to be some area in which people wanted to set the rules, this would probably be among the first. [...]

For whatever reason, we seem to have modules designed to work very hard to prevent people from doing the things they want to do. [...]

People’s stance on abortion might then really be a stance based on the output of certain modules designed to limit other people’s promiscuity. [...]

Further, because they didn’t know why they wanted to constrain other birds’ sexual behavior, they would be forced into contradictory positions. [...]

My musings here are intended to give a sense of what the right answers might look like, broadly, to the question of why people judge others’ actions and condemn them. Good explanations of moral condemnation should account for the basic phenomenon: stopping other people from doing various things.In order to do this, I’m going to talk about birds. Why might birds have modules that cause them to control what other birds get up to in the privacy of their own nests? [...]

One might wonder why morality evolved in the first place, but a key feature of morality is that humans seem designed to accept—even create—rules that constrain their own behavior, as long as these rules constrain others’ behavior as well.

Morality can be seen as the informal equivalent of a justice system. I’ll agree to rules that specify that I can be punished for various deeds, but only as long as everyone else is subject to the same rules. This makes sense; we shouldn’t expect evolved creatures to be designed to consent to limit their own options, but not others’. 

This means that a key—perhaps the key—feature of moral cognition is that morality, to be stable, must include impartiality, the idea that rules apply equally to everyone. Impartiality is crucial because without it, rules become nothing more than a way from some people to coerce others. As one might expect, humans don’t tend to want to accept rules that bind them but not others. Imagine the fate of one of our fictional birds that agreed to a rule that prevented him, but no other birds, from mating; such a rule would be, from this bird’s (genes’) perspective, an evolutionary disaster. Such complacent designs would be quickly selected out. [...]

Once morality is seen for what it is—a group of people’s decisions about what acts will result in punishment—then it is clear that evolved systems ought to be designed to try to prevent others from using these moral sticks differentially to their own advantage. The uniform application of moral principles prevents this; hypocrisy undermines it. (Robert Kurzban - Why everyone (else) is a hypocrite : evolution and the modular mind)
Especially the Catholic rule that the first sexual intercourse between a man and a woman binds both of them forever should instinctively appeal to conservative second-class men (beta males).

It must be said, of course, that evolutionary psychology is fundamentally amoral, or at least represents moral relativism. Nevertheless, it provides significant insights.

Those who do not deny evolution cannot entirely deny an evolution of the mental or psyche. Thus, feelings such as shame could possibly be explained in evolutionary terms. Moral intuitions might be entirely explicable, which would weaken an important element of natural law.

The mercilessly bloody brutal, amoral evolution, which takes place according to the criteria of the naked survival and the ruthless sexual success, is obviously conceded by Thomism. But what results from this? The animal body and the animal psyche of man are a product of this described evolution. Now the soul added by God is supposed to take this body and psyche also as moral standard. This seems to be very questionable. Moreover, for me the Thomistic theory of species is not compatible with the theory of evolution. Because from that theory follows either that all individual organisms have their own individual essence (so that there are as many essences as there are organic beings), or that there is in principle only one essence, namely that of organic life itself (all animal species would be only modifications of this one essence). In the first case almost all characteristics are essential, in the second case almost everything is accidental.

Accordingly, the Thomist can no longer appeal to a supra-individual form of man as a moral template. The following would apply:
At any rate, the good Aristotle talks about is not the good of the species, but the good of an individual. (MICHAEL HAUSKELLER - Telos: The Revival of an Aristotelian Concept in Present Day Ethics.)
For Aristotle and Thomas Aquinas, human procreation, from the point of view of animality, was for the sake of preserving the (in some sense eternal) species. Man has sex, eats, and dies for that purpose. Sexuality, nutrition and dying are teleologically oriented. And every organ and every cell in man has the preservation of man as its highest goal in the animalistic hierarchy of ends. But all this is no longer tenable.

Evolution should mean three things:
  • Self-copying (the individual has priority. When an individual has successfully copied itself with small deviations, all copies can be given the name of a species or kind for the sake of simplicity and convention, so that they can be grouped together and named. But there is nothing metaphysical in this.)
  • Adaptation to the environment and circumstances
  • Progress of the universal entropy
The human being in itself or the idea of an animalistic human being can no longer be properly brought into natural law.

Thomistic natural law is a creation of the Thomists, not of Thomas Aquinas, who only provided the essential impetus for it. On the one hand, it is very strange that a supposed philosophical basis of morality took so long to be fully developed in the first place and finally made available to the public. On the other hand, it seems as if one simply wanted to erect a theoretical edifice on the basis of a very old unquestioned cultural habit that had to be preserved at all costs.

Why homosexuality should be considered natural will be explained by means of two longer sections of text:
The whole phenomenon [homosexuality] was allocated to the realm of psychopathology. It was considered a symptom of degeneration and those afflicted by it as sick people. Although this view now has fewer adherents than it did some years ago, before its former main advocate Krafft-Ebing himself tacitly dropped it in the later editions of his Psychopathia sexualis, it is still worth remarking that sexually inverted people can otherwise be perfectly healthy and, apart from accessorial social factors, do not feel worse than all the other healthy people. If one asks them whether they have any wish to be different in this respect, one quite often receives a negative answer.

All these attempts to explain homosexuality were misguided because the phenomenon was entirely isolated and no attempt made to connect it with other facts. Those who regard “sexual inversions” as something pathological or as a ghastly and monstrous anomaly in mental development (the latter being the view sanctioned by philistines), or indeed as a vice acquired by habit or the result of a monstrous seduction, should stop to think that there is an infinity of transitions from the most masculine male, through the feminine man and finally the male sexual invert, to hermaphroditismus spurius and genuinus, and from there, through the tribade and the virago, to the female virgin.

Incidentally—and this not only supports my theory but is actually explained by it— there is no sexual invert who is just an invert. From the outset all are bisexual, that is, capable of sexual intercourse with both men and women. It is possible that they later actively promote their own unidirectional development toward one sex, pushing themselves toward unisexuality, and finally causing heterosexuality or homosexuality to prevail in them, or allowing themselves to be influenced by external causes to move in one of those directions. However, this can never extinguish their bisexuality, which continues to reveal its temporarily suppressed existence again and again.

A connection between homosexual phenomena and the bisexual predisposition of every embryo in the animal or plant kingdom has been recognized repeatedly and, in recent times, with increasing frequency. The novelty of my account is that, unlike those investigations, it does not see homosexuality as a regression or an incomplete development, i.e., a defect in sexual differentiation, and that it no longer regards homosexuality at all as an anomaly that stands in isolation, intruding into the otherwise complete separation of the sexes as a remnant of an earlier undifferentiated condition. Rather, it includes homosexuality as the sexuality of intermediate sexual forms within the continuity of intermediate sexual forms, which it regards as the only forms occurring in reality, while the extremes are only ideal cases. According to this theory, just as all organisms are also heterosexual they are all also homosexual.

Corresponding to the more or less rudimentary development of the opposite sex, the predisposition for homosexuality is still present, however faintly, in every human being. This is particularly clearly proved by the fact that at the age before puberty, when a relative lack of differentiation still prevails and the inner secretion of the gonads has not yet finally determined the degree of unidirectional sexual development, those rapturous “juvenile friendships” that are never entirely devoid of a sensual aspect are the rule among both the male and the female sex.

People beyond that age who go into extreme raptures over “friendship” with their own sex carry a strong element of the opposite sex in them. However, a much more advanced intermediate form is represented by those who enthuse about companionship between the “two sexes,” who, without having to keep guard over their own feelings, are able to have comradely relations with, and become confidants of, the opposite sex, which is, after all, their own, and who try to impose such a “pure” and “ideal” relationship on others who find it less easy to remain pure.

Nor is there such a thing as a friendship between men that completely lacks an element of sexuality, although, far from representing the essence of friendship, the very thought of sex is embarrassing to friends and opposed to the idea of friendship. That this is correct is sufficiently proved by the mere fact that there can be no friendship between men if their external appearance has not aroused any sympathy at all between them and they will therefore never come closer to each other. A great deal of “popularity,” protection, and nepotism among men derives from such relationships, which are often unconsciously sexual in nature. [...]
Finally, a large number of homosexual acts have also been observed among animals.

F. Karsch has made a commendable (albeit incomplete) compilation of cases from the literature. Unfortunately the observers hardly ever report anything about the degrees of “masculinity” or “femininity” in these animals. Nevertheless, there can be no doubt that here we also have a proof of the validity of our law for the animal kingdom. If bulls are locked up and not allowed near a cow for a lengthy period, acts of sexual inversion can be observed between them after a while: some, the more feminine ones, take to this sooner, others later and some, perhaps, not at all. (The large number of intermediate sexual forms has already been established for cattle in particular.) This proves that they have the predisposition, except that previously they were able to satisfy their need in a better way. The behavior of captive bulls is no different from that of human beings in prisons, boarding schools, and monasteries.

Among animals too there are intermediate sexual forms, and the fact that they know not only onanism (which occurs among them as it does among humans) but also homosexuality seems to me one of the strongest confirmations of the law of sexual attraction formulated above.
(Otto Weininger - Sex and Character. An Investigation of Fundamental Principles. Translated from German by Ladislaus Löb. Edited by Daniel Steuer with Laura Marcus)
Heterosexual orientation is a prime example of a psychological adaptation— roughly 94 to 98 percent of men and 98 to 99 percent of women have a primary orientation toward heterosexuality. Any orientation that lowered the likelihood of successful reproduction would be selected against. The persistence of a small percentage of primarily or exclusively lesbian women and homosexual men poses a genuine evolutionary puzzle, as noted in Chapter 4. Sexual orientation has a modest heritable component (Bailey et al., 1999). Homosexual men have lower rates of reproduction than heterosexuals (Bobrow & Bailey, 2001; McKnight, 1997; Muscarella, 2000).

One evolutionary explanation of male homosexuality is the kin altruism theory (Wilson, 1975). According to this theory, genes for homosexual orientation could have evolved if they led homosexuals to invest heavily enough in their genetic relatives to offset the costs of forgoing direct reproduction. Early tests of the kin altruism theory, however, received no empirical support from studies of gay and heterosexual men. Gay men did not differ from heterosexual men in their likelihood of funneling resources toward kin (Bobrow & Bailey, 2001; Rahman & Hull, 2005). In fact, gay men reported being slightly more estranged from their genetic relatives, contrary to the kin altruism theory. In contrast, several studies in Samoa did find greater avuncular tendencies among male homosexuals (fa’afafine)—specifically, compared to their heterosexual counterparts, fa’afafine did invest more in nieces and nephews (Vasey & VanderLaan, 2010). They reported babysitting more for them, buying them toys, and investing money in their education. Moreover, crosscultural studies of male androphilia expressed in a transgendered form do find elevated levels of kin altruism (VanderLaan, Ren, & Vasey, 2013). Although no work has yet examined whether these behaviors increase reproductive fitness of genetic relatives enough to offset the costs of not reproducing directly, the kin altruism theory may still be in the running as an explanation, awaiting more extensive research.

A second evolutionary theory is called the female fertility hypothesis, which suggests that genes for male homosexuality can evolve if they produce an increased reproductive rate in the female relatives of male homosexuals—a reproductive advantage that more than compensates for the lower rates of reproduction of gay males (Iemmola & Camperio, 2009). This could occur in resource-stratified societies in which women with highly attractive feminine and fertile qualities “marry up” in social status, which is known to occur (Barthes, Godelle, & Raymond, 2013). One test of the female fertility hypothesis involves examining the reproductive rates of female kin of homosexuals compared to the female kin of heterosexuals. Evidence has steadily been accumulating that, although male homosexuals produce about a fifth of the number of offspring as heterosexual men, the maternal female relatives of gay males (e.g., their mothers, maternal aunts) indeed produce significantly more offspring than the maternal female relatives of heterosexual men (Iemmola et al., 2009). These results have been found by other researchers (e.g., Rahman et al., 2008). Mathematical models and anthropological data also support the female fertility hypothesis, coupled with upward mobility of attractive feminine women (Barthes et al., 2013). If future research continues to confirm the female fertility hypothesis, it would partially resolve the Darwinian paradox of male homosexuality—that genes transmitted through the maternal line simultaneously increase the likelihood of producing homosexual males while increasing the reproductive rates of females.

Another theory proposes that we should focus on the functions of homoerotic behavior per se, rather than sexual orientation (Muscarella, 2000). Evolutionary psychologist Frank Muscarella proposes a specific function for homoerotic behavior: alliance formation. According to this theory, homoerotic behavior by young men with older men provides a strategy for gaining allies, boosting themselves up the status hierarchy, and ultimately gaining greater sexual access to women. The alliance formation theory has several virtues, such as focusing on the functions of homosexual behavior and an emphasis on cross-species comparative framework (same-sex sexual contact has also been documented in other primate species such as bonobos).

Nonetheless, the theory encounters several empirical difficulties. Although it might explain practices in a minority of cultures, such as ancient Greece or certain New Guinean tribes, there is no evidence that the majority of young men in most cultures use homoerotic behavior as a strategy of alliance formation. Indeed, non-sexual same-sex alliances appear to be the norm and are commonly not accompanied with any sexual activity. Furthermore, there is no evidence that men who engage in homoerotic behavior succeed more than those who do not in forming alliances or ascending in status.

In sum, of the three evolutionary theories of homosexuality thus far advanced, the kin altruism theory has received mixed empirical support, while the female fertility hypothesis has accrued the strongest empirical support. More extensive cross- cultural tests of these theories are needed, although scientists are now making some progress in explaining what has long been considered an evolutionary paradox.
(David M. Buss - Evolutionary Psychology: The New Science of the Mind. Sixth Edition)

To feel homosexual feelings and to act on these feelings is quite natural. Because if this (teleological) inclination is something completely normal, then the fulfillment of this inclination cannot be completely perverse. According to the view of an old natural law expert, purposive functionality is always a question of value. But this question can never be settled unambiguously. A purpose is most likely neutral from an objective viewpoint. The deliberate failure to achieve a purpose can, under certain criteria, be regarded as neutral, bad, or even good.

Someone who believes in objective values in the world must accept a divine authority that establishes those values and sets them into things. However, that only works if you have a proof of God that can at least halfway convince any reasonably intelligent person. However, that would still not be the end of the matter. Because one must find additionally a person who can grasp these objective values unclouded. That would be an infinitely more difficult challenge than the proof of God itself.

From the fact of the heartbeat (or the power to pump the blood), which runs functionally or teleological in an unconscious way, a commandment or prohibition cannot be derived, like: Thou shalt not interrupt the heartbeat!

Also for example with petting between teenagers there is no imperative which comes from the excited sexual organ or libidinous power of the boy, like: Should it come to it, you shall only ejaculate into the vagina!

If my soul is thrown into a world of pure wills to power (Nietzsche), i.e. if it is connected with one of these many wills to power, then nobody will claim that the soul should follow the nature of this will. The same is true if my soul is thrown into a world of pure wills to death.

The Thomists say that rationality is connected with animality and that the latter is to be directed rationally. However, animality as such does not understand an ideal and idealized ought. Moreover, if rationality completely dominates and directs animality, then there should be no moral problems at all. At this point, the concepts of original sin and hereditary sin are always brought forward, which, however, are highly problematic for many reasons. And: If animality is based on the will to power or the will to death, how should rationality still be able to relate to this animality?

The ought is a language-communicative category and therefore ideally requires a preceding speech act of a demand (imperative) or request. In the unconscious nature of the human organism, with the exception of the brain, there is not even potentially such a speech act.

The human body may be teleologically structured as an unconscious system and run accordingly in many of its parts. Nevertheless, I cannot derive a moral ought from it, since it does not represent a will of another (a foreign will), unless the teleology of the body is the will of God. But then the divine will is badly communicated by God himself, which would contradict his perfection. God would have to speak completely unambiguously in the mother tongue of the respective "body owner". God as Jesus communicates perhaps somewhat more clearly, but he either demands the impossible or gives us the Golden Rule as a moral principle, with which, however, little can be said against sexual deviations. Moreover, Jesus' speech is not always clear, since one never knows whether it is meant merely allegorically or literally. It is also not entirely clear whether Jesus is more conservative or rather progressive.

So the book of human nature is ruled out as a book of moral commandments.

According to Thomism, it is only the teleology of one's own body that prescribes rules, never the teleology of a foreign human body. Strangely enough, there seems to be an infinite gap between one's own body and the foreign body, which, however, has to be proved systematically. That the teleology of other animal bodies has no direct moral significance for me is strange indeed. It sounds as if there is a tacit Kantian dualism between empirical ego and intelligible ego, with the latter ego dictating to the former what is to be morally done.

According to Kant, there is no obligation to God because he is not an object of experience. Moreover, according to Weininger, any ethics that God commands us, as it were, by means of stone tablets (and perhaps through our bodies) is heteronomous and thus no longer in harmony with true autonomy of self and will.

Let us leave out the ought, namely God's will, and remain merely with the have to or the must. I have to (must) do or not do this or that to avoid or achieve this or that. God would therefore demand nothing from us. It is then up to us where we want to go after death. Our nature would be a pure mechanism, in principle an immanent mechanism, however with metaphysical consequences.

If I decide to throttle my heartbeat to a standstill, and if I decide to direct my ejaculation towards the bedding while petting with orgasm, I have activated certain "switches" that can take me to hell. However, this is pure consequentialism, a metaphysical or theological one, if you will.

While the Catholic Church does state that it can flip the "switches" through such institutions as baptism, sacraments, confession, and absolution, this depends on faith in the institution of the Catholic Church.

We must also leave aside the idea of grace and that of predestination, for they would create even more confusion.

We must also consider it unproblematic, although it is very problematic, that we have no direct idea of hell, that God does not give us a preview of what may come to us, including the idea of heaven, and that we do not know exactly which "switches" to pay particular attention to that, if activated or not, will lead us to one place of transcendence or another. Someone might be tortured because he happened to choose B instead of A. That would be very odd and cynical.

Furthermore, the moral values of "switches", functions and purposes are exclusively bound to the heavenly or hellish consequences. Thus, something is morally bad only because it results in hell.

However, if one wants to go to hell, a revaluation takes place. Two points besides love and compassion toward Satan, who is still perfectly good as a pure spirit nature but damned only because of an irreversible error, and besides hatred for the hypocrisy, power obsession and unworldliness (out of touch with the world) of the Catholic Church, perhaps give a reason to want hell as an anti-Ecclesial place:

1. being in hell is infinitely better than not being (so say the Thomists).

A divine thread of existence keeps one alive even in hell, even if that thread is extremely long and thin all the way down there. But it is nevertheless existing, so that a connection to God still exists. The thread could not be even thinner and longer without snapping. If this happens, one would be completely separated from God and thus annihilated.

2. the inhabitants of hell perfect the heavenly kingdom (so say the Thomists).

Thus, hell is not a place of evil, because evil is only the absence of good, that is, it does not exist at all, but hell is also a place and part of perfecting good.

The question of value, thus morality itself, is turned on its head here. Why should it still be bad to do evil on earth?

I have noticed that Feser, who begins his book with remarks on Parmenides and arrives at Aquinas after a few stopovers, basically returns to the teachings of Parmenides without intending to. 

For Parmenides there is really just one thing in existence: being itself, solitary, undifferentiated, and unchanging
as Feser points out. Now one has to read what Feser has to tell about the God of Aquinas. To put it bluntly, it is the same as with Parmenides. The qualities of the Thomistic God are actually only 
different ways of referring to what is in itself the same thing, Being Itself. (Feser)
While Parmenides speaks of illusions of plurality, Feser, in keeping with the philosophy of Aquinas, speaks of "fragmented and imperfect reflections"

Schopenhauer summarizes the Eleatic philosophy:
The Eleatic philosophers are probably the first who became aware of the opposition between what is intuited and what is thought, phainomena and nooumena. The latter alone was for them true being, the ontôs on. Of this they then asserted that it is One, unchangeable and immovable. They did not claim the same of the phainomena, i.e. of what is intuited, appearing, empirically given, which would have been outright ridiculous. (Arthur Schopenhauer - Parerga and Paralipomena Short Philosophical Essays Volume 1)
Parmenides says that there is no such thing as plurality and that change is impossible. He says the very notion of change is incoherent and even our own selves are to be entirely deceptive.

So according to the philosophy of Parmenides, (true) reality is basically one, immutable, and unchanging, and all plurality, change, and motion are mere illusions of the senses. But Parmenides does not deny the illusions as such. He only says that what the illusions represent does not exist as things (in) themselves, i.e. does not exist in any sense independently and self-sufficiently.

Thomistically speaking, the world is also ontically and ontologically illusory because it does not exist independently and self-sufficiently either, but the Thomists talk (mere talking) this fact out of their heads, unlike the followers of Parmenides, that is, they only act as if the world was not ontically and ontologically illusory. The things of the world would be as real (better said, unreal) for the Thomist as the illusions are "real" or unreal for Parmenides. Both the Eleatics and the Thomists deny a mundane (immanent and natural) principle of intrinsic and self-sustained motion in the world. If the Thomists wish to distinguish themselves from the Eleatics, then this will only happen nominally, thus only with empty words, which pretend to be meaningful analogies.

My empirical (bodily) and introspective experience (cogito, ergo sum) tells me that at least in myself there must be individual (in some respect unmoved) self-motion (my continuously progressing subjectivity, which I experience as a kind of being for itself and distinct from other things), which in a sense can be considered as semi-independent. On the one hand, I am an individual with real power (this cannot be an illusion since it is a fact of inner and outer experience), but on the other hand, I am also dependent on certain conditions of existence such as air for breathing, a certain air pressure, functioning organs, sensory stimuli, solid ground under my feet with Earth-like gravity, food, and water, etc. Thus, I (the I understood as a fragile mental fabric, which consists entirely in self-reflection, and which springs from the basis of life) rest and rely on myself (the ego), on my individual basis of life (the immediately given real), which I can recognize as a narrow one, limited by other natural individuals, and partly dependent on and also affected by them, but nevertheless as a relatively solid and firm one. It's not as if, for example, the air actively breathes me into existence. On the contrary, I autonomously deprive the atmosphere of some oxygen. And if there was no oxygen suddenly, then I would not immediately lose my existence. When, for example, my surroundings get colder, my body automatically produces heat and I consciously look for warmer areas, all on my own. I assert myself against the outside world and forcibly incorporate parts of it into myself. In that respect, one is anything but passive and dependent. 

But according to Thomism, all this is (being for and of oneself and being independent and asserting one's existence), however, unreal (strictly speaking, only God is real) because as we can remember only God is the one who is 

in the strictest sense really doing or actualizing anything. (Edward Feser) 
For me, something is real when it can do something. That should be common sense. Philosophically speaking, there is neither a comparative nor a superlative to the adjective realSomething is real or it isn'tEverything else is just playing on words.

For if there were a transcendent being, our actions or all actions in nature in one form or another would ultimately be the actions of that very being. In Thomist monotheism, analogously speaking, the power to think, to create, to persist in existence, to move, and so on would lie solely in the corresponding divine principle, i.e. all power would be distributed only one-sidedly.

Feser's course of argumentation, which runs through his entire book, thus takes a somewhat absurd turn. In the end, the God of Aquinas is the God of the Eleatics, whom Feser had not taken seriously and smiled at. This Eleatic God, now dressed in a Thomist garment, so to speak, would be like a puppet master, and we would be like his puppets, which only really exist when he plays with them (if he should no longer play with them and throw them into a corner, he must look at them or at least think of them, otherwise they would immediately pass into nothingness). But while this God is playing, he falls into a strange deception, the deception that the puppets act autonomously and self-sufficiently, that is, on their own genuine (moral) responsibility and separately from his compelling and irresistible influences. He simply forgets while playing that he is pulling the strings, that he is solely responsible for every movement (bodily and mentally), power, existence, substantiality, purposefulness, (intellectual) form and matter of the puppets (they are only divinely welded together bundles of those mentioned heterogeneous ontological parts that God has also created out of himself or his omnipotence)For some inexplicable reason (now as a pseudo-viewer) he doesn't like most of their behavior at all. The abstruse and tragicomical consequence is that he punishes them (actually an extended and augmented part of himself) for it.

The Thomistic God is not only the God of the Eleatics but above all a God of self-deception and delusion (the Catholic Thomists would have me burned for that statement if they were in power). He/She/It is caught in self-deception, but also those who believe in him/her/it. 

So Feser's God is pure (reified) being. Then we first listen to what Schopenhauer has to say about abstract words like being:
[A] concept [...] has a sphere, which is the totality of everything conceivable through the concept. Now the higher the level of abstraction, the more is lost, and therefore the less is thought. The highest, i.e., the most general concepts, are the emptiest and poorest; ultimately these are just empty shells, as, e.g., being, essence, thing, becoming, etc. (Schopenhauer - On the Fourfold Root of the Principle of Sufficient Reason)
I think only the religious person can project all his or her religious and mystical or mystic (thus also dazzling and possibly misleading) feelings onto the empty abstraction of the word being.

The very expression being has no meaning if one does not want to understand by it the totality of all being (of all existing things), but a Theistic God is certainly not a multitude of things. Furthermore, the verb to be is ambiguous. It can express (as copula) the predication, but besides that, it can also express identity and existence. As a copula it has no meaning of its own, one could at most interpret it as a relation like "...falls under the term...", but one will hardly want to regard God as a relation. So he is not the relation of identity either. But if one understands to be in the sense of to exist, then the noun of this verb does not denote a thing, but at most(!), like (the) sleeping, a state of things. But God is surely not supposed to be a kind of state of things. If one would accept all the explanations just mentioned, one would have a Pantheistic God

God as pure being may no longer be logically complex, but he must at least be mystically complex since from an absolutely simple simplicity no worldly complexity can arise. The Thomists can say whatever they want. They will simply not be able to get rid of the complexity in the divine. If I call the simple simplicity A, I can say that from A follows only A, nothing more. This is all that can be spun out of it. At most, we have A = A, a simple tautology.  

Anthony Kenny criticizes the word or concept being if it is to be the only way to describe God:
Feser believes that the various arguments of Aquinas establish the existence of a God whose essence is to exist. That this is a nonsensical notion was briskly shown many years ago by a philosopher for whom Feser, rightly, has a great admiration. Peter Geach, in Three Philosophers, imagines the following dialogue: Theist: “There is a God”. Atheist: “So you say: but what sort of being is this God of yours?”. Theist: “Why, I’ve just told you! There is a God; that’s what God is!”. (Anthony Kenny - We have all been here before)
The question is whether the Thomistic God is at all still a Theistic God. I don't think so. The Thomistic God is deprived of any personality. We listen to Schopenhauer about a non-personal God:
However, even the assumption of a cause different from the world is still not theism. This requires not only a cause different from the world, but an intelligent, that is, knowing and willing, thus personal, and hence individual cause of the world; only such a cause is designated by the word God. An impersonal God is no God at all, but merely a misused word, a non-concept, a contradiction in terms, a shibboleth for professors of philosophy, who, after having had to give up the thing, try hard to slip in the word. (Arthur Schopenhauer- Parerga and Paralipomena Short Philosophical Essays Volume 1) 
Attempts to purify theism of anthropomorphism, while imagining that they touch only the shell, in reality strike at its innermost essence; by trying to conceive their object in the abstract, they sublimate it into a vague hazy form whose contour, in the attempt to avoid the human form, gradually dissolves completely, whereby the infantile fundamental idea itself finally evaporates into nothing. The rationalist theologians, for whom such attempts are characteristic, can be accused of flatly contradicting Holy Writ, which says: ‘So God created man in His own image; in the image of God created He him.’ (Arthur Schopenhauer- Parerga and Paralipomena Short Philosophical Essays Volume 1)
For personality is a phenomenon that we know only through our animal nature and that, therefore, separated from this nature, cannot be clearly conceived. To make such a phenomenon the origin and principle of the world is invariably a proposition that not everyone is readily able to grasp; much less can such a proposition be rooted and live in everyone’s mind naturally. On the other hand, an impersonal God is a mere philosophy professor’s fib, a contradiction in terms, an empty word to satisfy the unreflecting or to appease the police spies. (Arthur Schopenhauer - Parerga and Paralipomena Short Philosophical Essays Volume 1)
Feser says at the beginning of his book that Aristotle has a strong weapon against the teachings of Parmenides and Heraclitus with his concept of potentiality. One must first concede that the concept of potentiality is an immensely abstract concept. It is in principle an empty shell of thought. Would Parmenides and Heraclitus have been impressed by Aristotle's idea? I don't think so. They would ask him the following questions first: How and where does your potentiality exist? Does it exist in a space- and timeless transcendence or in the known immanence of the natural world? Heraclitus would especially ask: Is this potentiality in itself pure motionlessness and rigidity? If so, why should it be excluded from the overarching flux of things? I'm not convinced of your concept. If it's not pure motionlessness, then my philosophy is only reaffirmed with a new word.’ On the other hand, Parmenides would ask in accordance with his philosophy: Does your so-called potentiality belong to being or not? May it be just a subspecies of being? If so, we do not need to discuss it any further, because then we would only be dealing with a fake and pseudo-like thing. Next question: Is your potentiality causally inactive? Because for me there are no causally inactive properties or entities at all. There are no idlers.’ 

The second question of Parmenides is based on the following paper: No Simples, No Gunk, No Nothing by Sam Cowling:

As an aside, I doubt that Aristotle really solved Zeno's paradox with his concept of potentiality. The problem was not solved but merely moved elsewhere. 

If potentiality exists only as a concept in a human being's mind, i.e. only idealiter, then one must not use it without further ado in arguments that aim at something real, i.e. realiter. Bertrand Russel also sees problems in the concept of potentiality:
The concept of potentiality is convenient in some connections, provided it is so used that we can translate our statements into a form in which the concept is absent. ‘A block of marble is a potential statue’ means ‘from a block of marble, by suitable acts, a statue is produced.’ But when potentiality is used as a fundamental and irreducible concept, it always conceals confusion of thought. Aristotle's use of it is one of the bad points in his system. (Bertrand Russell on Aristotle in his History of Western Philosophy)
And Fritz Mauthner is very mocking and ironic about it:
Aristotle was the first to teach how to play catch-ball with the notion of potentiality. If the potential is actual or active, then certainly the whole scholastic system is acquitted on the charge of senselessness, and all teleology as well has a clear meaning. (Fritz Mauthner - Aristotle)
Feser insists so much that cause and effect are simultaneous. But if according to Feser, the effect is also the telos of the cause, then his view seems to me to be problematic. Let’s assume that we have a finished sculpture in front of us. The finished sculpture is an effect, but the sculptor is no longer present. It is clear that prior to the finished sculpture, sculptural activities must have taken place. Sculpting as the cause must have preceded the finished sculpture as an effect. The sculptor as a person and the rough marble stone must of course, logically, have been in touch at the same time. But the activity of the sculptor with his current vague idea of the finished sculpture preceded this sculpture. Achieving (causing) an effect as a goal (end) should actually take time (after all, an effect always has a degree of complexity that could not have been produced with a mere timeless snap of a finger). If causation is only simultaneous, then it is instantaneous, which is implausible if the effect is not to be an absolute point. For an effect will always be complex, so that it must first unfold temporally. A causal process takes time to elapse. Whether it takes a millisecond or years. So the beginning of the cause must precede the end of the effect. There may be simultaneity in between. Here’s Schopenhauer’s take on this philosophical problem:
According to the laws of causality and motivation, the ground must precede the consequent in time. This is absolutely essential, as I have demonstrated in detail in the 2nd volume of my principal work, ch. 4, pp. 41–2a to which I refer here so as not to repeat myself. Accordingly, one will not be misled by the example Kant cites (Critique of Pure Reason, 1st edn, p. 202; 5th edn, p. 248b), namely, that the cause of the warmth in a room, the stove, is simultaneous with its effect – as long as one considers that a thing is not the cause of another thing, but a state is the cause of another state. The state of the stove, that it has a higher temperature than the surroundings, must precede the imparting of the excess heat to its surroundings; and now, since any heated layer of air is displaced by any colder layer of air streaming in, the first state, the cause, and, as a result, the second state, the effect, are renewed as long as the stove and the room are not of the same temperature. Thus here the stove and the warmth of the room are not persistent, simultaneous cause and effect, but a chain of alterations, or a continual renewal of the two states, one being the effect of the other. But from this example we can see how even Kant’s concept of causality was unclear. (Schopenhauer - On the Fourfold Root of the Principle of Sufficient Reason)
On the other hand, the absurd assertion of many professors of philosophy of our day that cause and effect are simultaneous can again be refuted by the fact that in cases where on account of its great rapidity the succession cannot be perceived at all, we nevertheless assume it with a priori certainty, and with it the lapse of a certain time. Thus, for example, we know that a certain time must elapse between the pressing of the trigger and the emission of the bullet, although we cannot perceive it. We know that this time must again be divided between several states appearing in a strictly definite succession, namely the pressure of the trigger, the striking of the spark, the ignition, the spreading of the fire, the explosion, and the departure of the bullet. No person has ever yet perceived this succession of states; but since we know which state brings about the other, we also know in precisely this way which state must precede the other in time, and consequently that during the course of the whole series a certain time elapses, although it is so short that it escapes our empirical apprehension. For no one will assert that the flying out of the bullet is actually simultaneous with the pressing of the trigger. Therefore not merely the law of causality, but also its relation to time, and the necessity of the succession of cause and effect, are known to us a priori. If we know which of two states is cause and which effect, we also know which state precedes the other in time. If, on the contrary, this is not known to us, but their causal relation in general is known, then we try to decide the succession empirically, and according to this determine which of the two states is cause and which effect. The falseness of the assertion that cause and effect are simultaneous appears moreover from the following consideration. An unbroken chain of causes and effects fills the whole of time. (For if this chain were interrupted, the world would stand still, or to set it in motion again an effect without a cause would have to appear.) Now if every effect were simultaneous with its cause, then every effect would be moved up into the time of its cause, and a chain of causes and effects with still the same number of links would fill no time at all, much less an infinite time, but the causes and effects would be all together in one moment. Therefore, on the assumption that cause and effect are simultaneous, the course of the world shrinks up into the business of a moment. This proof is analogous to the one that every sheet of paper must have a thickness, since otherwise a whole book would have no thickness. To state when the cause ceases and the effect begins is in almost all cases difficult, and often impossible. For the changes (in other words, the succession of states or conditions) are a continuum, like the time they fill; and therefore also like that time they are infinitely divisible. Their succession or sequence, however, is as necessarily determined and irreversible as is that of the moments of time itself, and each of them with reference to the one preceding it is called “effect,” and with reference to the one succeeding it, “cause.” Every change in the material world can appear only in so far as another change has immediately preceded it; this is the true and entire content of the law of causality. But in philosophy no concept has been more wrongly used than that of cause, by the favourite trick or blunder of conceiving it too widely, of taking it too generally, through abstract thinking. (Schopenhauer - The world as will and representation volume 2)

The blogger ATHEISM AND THE CITY draws attention to something that Feser does not mention in his window and brick example:
Using Aristotle, Feser also denies temporal causality in favor of simultaneous causality. He uses an analogy of a brick hitting a window that shatters it as a result and tries to argue that their is no temporal order of events between the brick being thrown, it hitting the glass, and the glass shattering as a result of being hit. There is much debate over causality in science and philosophy, but I don't think Feser makes a convincing case against temporal causality here. The brick is clearly thrown before hitting the glass and its impact on the window causes the glass to shatter. For a window, the glass will bend slightly inward from the impact of the brick before shattering under the pressure. (
Trick Slattery has dealt intensively with the question:
‘Whenever someone is allowed to use two different meanings of a word that are so closely related, it makes it easy to throw such words in the mix.’ Aristotle distinguished between what he termed accidental causality (cause preceding effect) and essential causality (one event seen in two ways). For essential causality, Aristotle uses the example of a builder building a house. This single event can be analyzed into the builder building (cause) and the house being built (effect). The idea of essential causality has been used as a way for people to contrive free will, among other things. Such contrivances usually stem from a misunderstanding, or poorly thought out conclusions of essential causality. Let’s go back to the example of a builder building and the house being built. We can picture these two things. It appears that as the builder builds, the house is being built. These don’t happen one after another, but at the same time. Certainly we can’t say that the builder is building without the house being built. Hence the term essential, the house being built (by the builder) is essential to the builder building (the house), and vice versa. First, I would like to call out what this view of essential causality really entails. It entails the generalized grouping of a pile of accidental causes. It then takes that generalization and compares two inherent parts of it that happen simultaneously. So for example, it may categorize a man picking up a hammer and a nail, then swinging the hammer to hit the nail, and the nail going into a board, as “builder building.” And the nail going into a board hanging on the wall of a partially built house as “house being built.” All of these individual events are causes and effects, with the causes prior to the effects, and we could, of course, break them down more into the real cause and effects that we don’t really see. The essential cause of the “builder building” and the “house being built” merely zooms out of space and time to grab a section of happenings and group them all into one event. It then focuses on two parts of the zoomed out block that are essential to each other, which happen within the same block of time. The “builder building” might happen in the block of time from time X to time Z, and the “house being built” would happen within that same timeframe. So from the perspective of viewing a block of action within a specific block of space and time, and categorizing such block as a single event, certainly we cannot separate out the categorizations. So how do some people use essential causality to contrive free will? First, it allows them to disregard the type of causality most mean, even though this other usage is not the important usage for the free will debate. If they can say that the effect is simultaneous with the cause, they can conflate this with the type of causality the determinist or incompatibilist may be talking about. Whenever someone is allowed to use two different meanings of a word that are so closely related, it makes it easy to throw such words in the mix. Especially when the person at the other end might not be familiar with the words “essential” and “accidental” as applied to causality. Another way it’s contrived is by suggesting that decisions can be “essentially caused” in the sense that a decision being made and the person deciding are essential to each other. It’s a way for them to frame that into what seems at first like an act of volition that is it’s very own internal cause. But this is a mistake. Even if we accept the idea of essential causality, that does not mean that something didn’t cause the builder building house/house being built in the first place. It does not allow us to frame the essential cause into something outside of what caused it. In my opinion, I don’t think that an essential cause should even be labeled a “cause.” Give it some other name to avoid confusion and conflation. If simultaneous, the only reason we can say that “the builder building” is the cause and the “house being built” is the effect is if we move into the actual causes and effects that show the progression: the accidental causes. Otherwise, if both were the cause and effect of each other, we’d have to say “the house being built” is a cause of “the builder building.” Of course that’s counterintuitive. Why? Because we know the progression of those “accidental” causes. We know that the builder lifting up a hammer precedes the nail going in. If we didn’t, how could we possibly consider one a cause of the other, or consider that such a simultaneous event contains both a cause and effect within it? Rather it’s simply all the same event (builder building house/house being built) summed up within a given block of time. Yet there are some people with a wee bit o’ knowledge of these philosophical terms who will use them to their advantage as soon as someone talks about causality as it applies to free will. Don’t let them. It’s not pertinent and is just used to deflect the subject matter. Not only is essential causality not compatible with free will, when someone uses it for such a topic, they’re playing a shell game. They are trying to suggest to you that this type of causality plays a role in the usage of the term “cause” for the debate, when it doesn’t. As a side note, I’m also not a fan of the words “accidental” and “essential” to describe these different types of causes. Today, such words are way too ambiguous and easy to confuse with the common usage of such words. A common usage might, for example, imply that a cause (such as an essential cause) would have a purpose (not done on accident). Or that a cause that precedes its effect does so in some non-forced way (happens by accident). This isn’t what’s meant by these words. The effect of an accidental cause would be just as “essential” to it if we used the common usage of the word essential. Confusing words just muck up the water. I cannot stress enough the importance of clarity. It’s unfortunate that I have to use such words to even address them as something that shouldn’t be used for the free will topic. If I didn’t have more than one person try such a shell game with me, I would have left this brief chapter out entirely. I would never have thought it important enough to address. But due to my own causality, I decided it important to note these differences in the word “cause” to avoid any ambiguity and to prevent any detractors from going there. (Slattery, ‘Trick - Breaking the Free Will Illusion for the Betterment of Humankind)
Sometimes you get the feeling that according to Aristotelian and Thomistic philosophy one only has to look at an object briefly in order to have (receive) its complete concept in the mind/soul (a kind of spooky telepathy). So you wouldn’t need the item for further inspection anymore, because you could now extract all the essential information from the finished concept in your soul/mind and because the concept would be identical with the ontological form of the item. But how then could a conceptual error be possible? If I have an incomplete or false concept in my mind, is there also in my mind a fragmented, dispersed, and disruptive form? So I’m just gradually building this form/concept together? Can I remodel forms arbitrarily? Could there be fragments of forms that I can laboriously collect and put together to perhaps discover shockingly at the end that the whole was useless? How can I be sure that the conceptual form with which I want to win debates is complete and error-free? If there is no guarantee, what advantages does this theory have over others?

If I consciously see a certain animal like a dog and identify it as a dog, then according to Aristotelian and Edward Feser's theory I also have the form of the dog in my intellectual soul. But the form of the dog is the soul of the dog, it is the life principle of the dog. Am I supposed to have created this within myself? A not yet materialized doggish life force or canine principle out of nothing or from nowhere? That would be very strange. Or does the form occur only once in the dog, and I have just mystically united myself with this form? That way I could know what it would be like to be a pure universal dog. Moreover, wouldn't the dog form, which is no longer an intellectual form, then do anything to materialize itself in such a way that it tried to collect the molecules of my brain? Wouldn't it thereby damage my body? After all, the intellectual and concept grasping soul already forms a hylomorphic intimate unit with the bodily matter, otherwise, it could not move the body and control its animal and vegetative functions. Further, would not the matter be able to act back on the intellectual soul? There is a strong suspicion that Aristotle advocates a kind of Cartesian dualism. At least, according to Boris Hennig (who also criticizes Aquinas), there seems to be no great difference between Descartes and Aristotle: 
When Descartes calls the mind an immaterial substance, he seems to break with the Aristotelian tradition in at least two ways. First, Aristotle calls the soul of a living being its substantial form, and this seems to conflict with its being a substance. Second, when Descartes characterizes the thinking subject as an immaterial substance, he seems to separate it as a distinct thing from the embodied human being, whereas an Aristotelian could simply say that the thinking subject is the human being itself. I will show that in both respects, Descartes does not differ as radically from Aristotle (and Aquinas) as one might suppose. (Boris Hennig - The Inner Man as Substantial Form) 
When I intensively examine a single tadpole for the very first time and for a whole day and I know nothing but this single tadpole, would I have to "see" the form of the frog in it? Or would I have to wait until the tadpole has turned into a frog? So the theory would then imply a kind of ad hoc/post hoc mixture (ex post facto justification)? When I examine a particular tree species, I always have to go back to the view of the tree to get new essential details about it. Without this going back one would only be at loss and could just fantasize about the tree. Aristotle must have believed that he could absorb all forms easily. For he was very confident in his scientific statements: 
There is no quality more noticeable in [Aristotle] than his unhesitating confidence in the adequacy of the human mind to comprehend the universe[.] (Fritz Mauthner – Aristotle) 
But he was so often so very wrong. 

If the mind is identical to the form of my brain, then I can assume that certain thoughts about things are materially visible in the brain. Each particular thought as a particular form (that belongs to the whole mental form) has its materialistic realization in the brain. When 
a universal has [...] been grasped, it is Aristotle’s doctrine that imagery is still needed by the mind. ‘The soul never thinks without an image.’ (David Ross – Aristotle) 
So Aristotle should have better said that the concept is merely the form of my fantasy image. That would be a much more elegant theory. When I think of the form of the imagined, I am really identified with it because it is my imagination. That would indeed make sense. Unfortunately, that's not the Aristotelian theory. 

When Aristotle emphasizes that human thinking must always and without exception make use of images of the imagination that derive from sensory perception (phantasmata or auditory and visual copies of reality, which are usually strongly attenuated in their impression and intensity) and are therefore essentially somatic (physical), he thus indirectly and secretly admits that thinking is physical. The necessary coexistence indicates a kind of inner or underlying unity of both sides. In name only, Aristotle rejects it, that is, in mere academic and technical words. Experience sufficiently shows that the manipulation of our brain matter influences our thinking. This is a trivial obviousness.  

Physical and physiological processes are according to Aristotle essential to sense-perception. On this sense-perception, the grasping of forms should then also be dependent. Otherwise, we are back to the mysterious mystical and spooky telepathic knowledge of forms. But Aristotle did not yet know anything about the functioning of the senses, nor about the cognitive brain. Can the intellectual soul in an unborn fetus already receive or intuit forms? Perhaps not yet, because the ability to take up forms might be based both on a fully developed brain and on well-formed senses. We then quickly come to Aristotelian naïve realism 
but [Aristotle's] account of the transmission of colour from the external object to the eye is very difficult to understand. (J. L. Ackrill – Aristotle the Philosopher) 
I think naïve realism is no longer tenable since Locke, Berkeley, Kant, Schopenhauer (, today’s psychology of perception (cognitive sciences) and brain research, or neuroscience. Color as Qualia is of subjective nature and origin, and the individual human unconscious alone actualizes the potential for color perception (which lies in parts of the brain and especially in parts of the eyes stimulated by specific light energy), so as to speak the Thomistic language. The mind is merely the function of one organ, as digestion is the function of another. That means that consciousness is created by a primary (life or chemical) principle actuating one of its organs, the brain (the secondary). Color, therefore, exists only in a subjectivity. It is absurd to attribute colors to bodies, regardless of the subject. Alternatively, and more objectively speaking, one could say, like Schopenhauer, that color exists only in the retina of the eye. Either way, it is separated from the external object (the color is only projected onto the outside world, so to speak).

Here is what current science has to say about it: 
We think of color as a fundamental quality of the world around us. But in the outside world, color doesn’t actually exist. 
Color is an interpretation of wavelengths, one that only exists internally. (Eagleman, David - The Brain)
Aristotle thinks that external movements move my senses, which pass the movements on to the center of consciousness. This raises the question, why the original movement should remain unchanged from beginning to end. Why should it not be possible for the cognitive process to integrate a certain (subjective) movement of the perceiver himself so that the resulting movement would then have to be a new (changed) but still uniform one? What about the interpretation of the movement, who guarantees its correctness? 

One must also consider the following: 
In the traditional model of vision, perception results from a procession of data that begins from the eyes and ends with some mysterious end point in the brain. But despite the simplicity of that assembly-line model of vision, it’s incorrect.
In fact, the brain generates its own reality, even before it receives information coming in from the eyes and the other senses. This is known as the internal model. (Eagleman, David - The Brain)
Feser hardly addresses epistemological problems. But he must bear in mind that his Thomism is based on naïve realism. In other words, Feser skips the perceiving and representing subject and speaks about objects as if they are exactly as the eyes see them or the hand feels them, without regard to eyes that see them or a hand that feels them, thus completely neglecting the cognitive (neurological) apparatus. If one abandons that realism, a gigantic reinterpretation of Feser's Thomism is necessary.

Aristotelian-Thomistic concept formation theory must also clearly and brazenly (in fact unbelievably and implausibly) deny that there are precursors to concept formation in animals in order to guarantee some kind of exclusive immortality of human souls. Animals should have no access to conceptual forms at all, they would be, if highly developed, only nominalistic in the fullest sense of the word. But there are good reasons to assume that animals deal mentally with preforms or precursors of concepts, even if these are mostly controlled by instincts. And why shouldn't the human mind be completely nominalistic or language-game Wittgensteinian? (Feser conceals the fact that there are a gigantic number of modern nominalistic theories) Moreover, the Averroists, who were thoroughly Aristotelian, believed only in the one divine intellectual soul which is immortal, they did not believe in the immortality of the many individual human souls (the intellectual soul is only one by number for all humans). For the Averroists, the soul of man is inseparable from the body, and with the destruction of physical conformity, it is destroyed. Incidentally, the Thomists believe that Aquinas refuted the Averroists for good. That's of course not the case. The theory of the Averroists is just a bit more complicated, but that doesn't mean that it becomes untrue and is eliminated as an alternative way of thinking. 

Here is a brief confrontation between Bacon and Aristotle, which could be instructive for the whole subject:
The error of Aristotle, but even more so of the Aristotelians, lay in the assumption that they really possessed all truth already, namely that it was contained in their axioms, that is, in certain propositions a priori, or ones considered as such, and that, in order to gain particular truths, only deduction from those propositions was needed. An Aristotelian example of this was given by his books On the Heavens. In contrast, Bacon showed quite rightly that those axioms did not possess such content at all, that the truth did not already lie in the system of human knowledge at that time, but rather outside of it, and so could not be generated from within this knowledge, but first had to be brought into it. Consequently, universal and true propositions, with large and rich content, had to be gained first through induction. (Arthur Schopenhauer - Parerga and Paralipomena Short Philosophical Essays Volume 1) 
The scholastics, guided by Aristotle, thought: First we want to establish the universal; the particular will follow from it, or will find a place under it afterwards as best it can. Accordingly we want first to find out what belongs to being, the thing in general. [...] Bacon, on the other hand, said: We want first to get to know the particular things as completely as possible; then we will in the end come to know what the thing in general is. (Arthur Schopenhauer - Parerga and Paralipomena Short Philosophical Essays Volume 1) 
The guideline of Bacon in comparison to that of Aristotle should be the dominant one in scientific and even philosophical investigations. This means that both play a role, but Bacon's method is more honest, and therefore more effort should be devoted to it.

I found Edward Feser's chapter about concepts, forms, and immortality extremely confusing, which is probably also mirrored by my confusing remarks. And I still haven't understood how one should understand the distinction between the universal and the individual. Is it real or does it only exist in relation to reason? Thus it is maybe just a pure mind dependant thing, a pure abstract fantasy?

There's one more thing I want to say. Feser's constant complaints about modernity, that it has moved away from Aristotle to its great disadvantage, are not only somewhat annoying but also partly inappropriate. For modern times have not simply distanced themselves from Aristotle without a goal. For various reasons, they moved more towards Plato again and took up elements and basic ideas of his philosophy in order to integrate them into their systems. These systems may have little in common with Plato's philosophy here and there (if there ever was a closed one), yet they have to be called Platonic (humanism or modern cosmology/physics are or contain Platonisms, for example). Probably the current academic consensus (as in the Renaissance) sees Plato (who is also highly esteemed by Feser) as the greater philosopher than Aristotle (who is completely anti-philosophy of language, anti-linguistic turn and anti-linguistic relativity - in his view, his Greek mother tongue represents reality ontologically perfectly and objectively, which is very presumptuous, word superstitious and even word fetishistic in some sense -, anti-existential philosophy - ‘limit situations’ (Grenzsituationen) à la Karl Jaspers are completely unknown to him, that is, moments, usually accompanied by experiences of dread, guilt or acute anxiety, in which the human mind confronts the restrictions and pathological narrowness of its existing forms, and allows itself to abandon the securities of its limitedness, and so to enter new realms of self-consciousness, - epistemologically totally naïve - keyword naïve realism - and is on the way with outdated scientific assumptions - geocentric world view without evolution and without relativistic or quantum mechanical effects; and, for example, the assumptions that women have fewer teeth than men and that the brain is nothing more than a cooling system for the blood). That is why Feser's outcry echoes into nowhere.

Thomism may have its theological importance, but philosophically I don't get much out of it. For me, it's largely a conglomeration of negative expressions, combined with unclear representations. This seemingly rational theory edifice seems to be just a place of refuge to hide one’s fideism by using 
mostly unproven assertions plucked out of the air, and at the same time […] artificial subtleties that demand the finest of distinctions and rest on the most abstract of concepts, laboured combinations, heuristic rules, principles that balance on the point of a needle[.] (Schopenhauer)
The Thomists built a system 
whose content ultimately amounts to mere words, which are really only soap bubbles, to play with for a while, but which cannot come down to earth without bursting. (Schopenhauer) 
According to Anthony Kenny, even the most sympathetic treatment of the doctrines of the real distinction between essence and existence and the thesis that God is self-subsistent being 
cannot wholly succeed in acquitting them of the charge of sophistry and illusion. (Anthony Kenny - Aquinas) 
Three last quotations should form the final word:
Since scholasticism, really in fact since Plato and Aristotle, philosophy has been for the most part a continued misuse of universal concepts, such as, for example, substance, ground, cause, the good, perfection, necessity, possibility, and very many others. A tendency of minds to operate with such abstract and too widely comprehended concepts has shown itself at almost all times. Ultimately it may be due to a certain indolence of the intellect, which finds it too onerous to be always controlling thought through perception. Gradually such unduly wide concepts are then used like algebraical symbols, and cast about here and there like them. In this way philosophizing degenerates into a mere combining, a kind of lengthy reckoning, which (like all reckoning and calculating) employs and requires only the lower faculties. In fact, there ultimately results from this a mere display of words, the most monstrous example of which is afforded us by mind-destroying Hegelism, where it is carried to the extent of pure nonsense. But scholasticism also often degenerated into word-juggling. In fact, even the Topi of Aristotle—very abstract principles, conceived with complete generality, which could be applied to subjects of the most different kind, and be brought into the field everywhere for arguing either pro or contra—also have their origin in that wrong use of universal concepts. We find innumerable examples of the way in which the scholastics worked with such abstractions in their writings, particularly those of Thomas Aquinas. But philosophy, down to the time of Locke and Kant, really pursued the path prepared by the scholastics; these two men at last turned their attention to the origin of concepts. In fact, in his earlier years, we find Kant himself still on that path in his Proof of the Existence of God (p. 191 of the first volume of the Rosenkranz edition), where the concepts substance, ground, reality, are used in such a way as they could never have been if a return had been made to the source of those concepts and to their true content as determined by this source. For then matter only would have been found as the source and content of substance, and of ground (when it is a question of things of the real world) only cause, in other words, the previous change bringing about the later change, and so on. This, of course, would not have led here to the intended result. But everywhere, as here, there arose false principles from such concepts too widely comprehended, under which more could therefore be subsumed than their true content allowed; and from these false principles arose false systems. Even the whole of Spinoza’s method of demonstration rests on such uninvestigated and too widely comprehended concepts. Here Locke’s very great merit is to be found; in order to counteract all that dogmatic unreality, he insisted on an investigation of the origin of concepts, and thus led back to what is perceptive and to experience. Before him Bacon had worked in a similar sense, yet with reference to physics rather than metaphysics. Kant pursued the path prepared by Locke in a higher sense and much farther, as mentioned previously. The results of Locke and Kant were, however, annoying and inconvenient to the men of mere show who succeeded in diverting the public’s attention from Kant to themselves. But in such a case they know quite well how to ignore the dead as well as the living. (Schopenhauer - The world as will and representation volume 2)

Again, like medieval philosophers, Aquinas is an extremely technical writer, using a complicated scholastic vocabulary and discussing perennial philosophical problems within a specialised and esoteric framework of concepts. Between Boethius and Bacon there was hardly a philosopher prepared to write for amateurs and gentlemen. Even in comparison with other medieval writers, Aquinas is difficult for a philosopher to read. (AQUINAS: A Collection of Critical Essays, EDITED BY ANTHONY KENNY INTRODUCTION)

As a philosopher, St. Thomas Aquinas is both overvalued and undervalued. He is overvalued by those who regard him as a unique source of philosophic truth, whose ideas can only be adapted and never superseded by later thought and discovery. He is undervalued by those who think of him as being, outside theology, no more than an erratic commentator on Aristotle. (AQUINAS: A Collection of Critical Essays, EDITED BY ANTHONY KENNY INTRODUCTION)

Fox ITK ( comments:
Something that confuses me about this argument from ‘being composite’ used to support the idea of divine conservation. It seems as if it’s just an outright denial of the possibility of simples which are not composed of parts which I don’t think there’s a good reason to reject, and thus are not contingent upon there parts, or priority monism, of parts being dependent upon the whole (the cosmos) and also of metaphysical infinitism, and yet it seems to insist on mereological gunk which never bottoms out in some non composite part, yet mereological gunk doesn’t need sustaining in the sense of having some fundamental basic part holding up the whole chain of being. The weird thing is that God isn’t that simple non composite ‘part’ of objects as the argument almost hints at him being, by invoking a buck stopping simple, because it’s not a simple of composition but a source of sustaining that itself requires no further causing for its continued existence, but is the ‘sustaining cause’ yet God an all together different type of sustaining cause then to a part (which sustains it’s whole) and that is what I think, the intuition in the argument demands, and so there’s perhaps an equivocation going on. This seems to lead to the denial that really, parts sustain their wholes, because if there is no basic non composite part that comes together with another basic non composite part to form the first composite whole ans sustain all further parts and wholes, then God must sustain each level of parthood simultaneously (such that wholes are sustained by being caused to continue to exist by God, not by God acting on some fundamental non composite parts, because this is what the argument denies- there is no such first fundamental part such that God acts on it, and it then transmits that cause through the supervening compositions. If there were such fundamental parts (simples) it seems like the argument falls away, or at least becomes an argument from metaphysical composition, which odd given the intuition that fuels the argument is one regarding physical composition. The argument Ed invokes against Oppy on existential inertia seemed to read a little too much into Oppy’s position. Ed’s objection is that Oppy is being circularthe continued existence of a thing is dependent upon it’s power to keep it existing, but the power itself is contingent upon the thing that has the power existing, and so there’s a huge problem there. But Oppy seemed to deny that powers and substances where composites in this way, and Feser seemed to jsut insist they were. Regardless, inertia itself need not be a ‘power’ at all but merely the tendency to not go out of existence unless something else with the power to destroy that object should come into play. This eradicates the need to even think of there being some force or property that sustains objects in the first place that is either itself contingent upon a substance or is just inherent to what substances are. The point Ed presses about the principle of individuation seems to me very weak. ‘what distinguishes one simple from another?’ doesn’t that by which they are distinguished lead to composition? I don’t see why things like Cambridge properties, or spatial or temporal properties are like ‘parts’. Ed would accept that God has so called Cambridge properties, but being simple they aren’t parts, they are relations etc which are extrinsic. Why aren’t these enough to distinguish simples? As far as I see they would. Ed’s response was to go beyond composition at this point to ask ‘what caused these different extrinsic properties? And that’s a different argument entirely, and if this is where we get to then we have moved beyond the scope of the argument to support it, and so I’d deem the argument a failure (after all, Oppy could just appeal to say past events explain why the spatial properties are such and such (of which this would be an accidental cause, which need not persist as an essential cause would).
The possibility of atomless gunk, a thing whose parts all have proper parts, threatens theories about composition and fundamentality. Here is more from Fox ITK about essential causal series:
Obviously if there's a set of infinite train carriages that are totally static, and in need of an engine to move them, the lack of a first carriage, for which the engine can begin to pull (and start the series of carriages being pulled to move) would be problematic. But the assumption there is that it's not possible to have the series of carriages in motion due to a basic rule- as long as the carriage in front is in motion the next stationary carriage will be pulled into moving. I think the argument against this, is just question begging- that the moving of carriages needs to originate somewhere in something that is moving under its own power. The only basic requirement we can both agree on is that no carriage moves itself, or can move without a carriage in front pulling it into moving which is itself moving. But a series of an infinity of carriages moving this way is possible, and its possible without an engine or a first member being pulled by a member. I guess the niggling concern might be 'but what explains the motion of the carriages!' Again, we need to be careful of question begging against the series without beginning- here if there is motion, that is explained by the fact that for any carriage moving, it was brought to move by one prior to it that was in motion, and that is true of any and all carriages that are moving. What's left as a worry, beyond 'but that doesn't tell me why there's motion at all, or in the first place!' because 'why there is motion at all' is I think explained in terms of the moving of prior carriages. AS for 'in the first place' this assumes again, that the moving must 'originate' in some first carriage being pulled into motion. The theist arguing against infinite regresses obviously thinks that there's no reason to think one chain would be moving over another chain that is totally stationary. Yet I think they have no reason to think that the stationary carriages is default over the one where there is moving. What explains that, is that in one world there was prior to some time t no prior carriage(s) to n that were in motion. That would be true at one world but not the other.
On analogy:

The problem with analogous statements in rational theology lies on the one hand in the fact that either no or only a few true statements can be made about God. On the other hand, however, statements that cannot be paraphrased in such a clear way have no place in a scholarly or scientific language as rational theology wants to speak. If conceptual precision in statements about God is not attainable, then the undertaking of a scholarly theology is mistaken from the outset. And this dilemma is not solved by analogous statements.

Norbert O. Schedler provides critical remarks on the subject:
In summary, for the way of analogy to work, some direct, nonanalogous statement about God's nature must be made, or we can never know that to which our analogies point, which analogies are appropriate, and which ones are not appropriate. An analogy by itself is not illuminating. Some prior knowledge of that to which the analogy points is necessary. Another way of putting this is that "we don't . . . claim to know by analogy, but only to argue by analogy." What this means is that when someone asks you how you know that God is loving, you do not argue by analogy. You are expected to provide some justification for your claim based on some evidence. Given this evidence I can then show the analogy between His love and my love. But notice! This presupposes that the similarity is already known. We do not come to know by analogy. Yet this is exactly what the defense of the way of analogy tries to argue. We can use analogies only if we already know in a nonanalogical sense. (Norbert O. Schedler - Talk about God-talk. In: Philosophy of Religion) 
Neo-Aristotelian theory of forms:
To restate in this paragraph and the next what I said at the end of “Aristotelian Realism in the Theory of Universals of Feser’s The Last Superstition”: the anti-realism which I have been setting forth denies, of course, the identity of the form, nature, or essence which one human being has and by which it is a human being with the form, nature, or essence which another human being has and by which it too is a human being; the form, nature, or essence of the one is not identical with, but distinct from, that of the other. The anti-realism which I have been setting forth must also deny the identity of that intellectually existent concept or intention by which we intellectually grasp a human being as the human being which he or she is with the form, nature, or essence which he or she has and by which he or she is a human being. (
Sean Carroll on the conservation of momentum (which states that the momentum of a system is constant if there are no external forces acting on the system):
[W]e can learn about the natural motion of objects by imagining we can get rid of various nuisance effects, such as friction and air resistance, and then perhaps recovering more realistic kinds of motion by putting those effects back in later. 
This enormous, paradigm-shifting idea—in idealized situations where friction and dissipation can be ignored, physics becomes simple—was in large part responsible for helping to establish an equally influential, arguably more world-shattering concept: conservation of momentum. It might not sound like a principle of such dramatic import, but momentum is at the very heart of a shift in how we view the world, from an ancient cosmos of causes and purposes to a modern one of patterns and laws. 
Most important for our purposes, the whole structure of Aristotle’s argument for an unmoved mover rests on his idea that motions require causes. Once we know about conservation of momentum, that idea loses its steam. 
There is conservation of momentum: the universe doesn’t need a mover; constant motion is natural and expected.
The universe doesn’t need a push; it can just keep going.

Conservation of momentum immediately tells us that the Earth won’t go careening off in a random direction[.] (Carroll, Sean - The big picture)
Farewell to the classical concept of substance through modern physics:
On closer inspection, in fact, even the things that are most “thinglike” are nothing more than long events. The hardest stone, in the light of what we have learned from chemistry, from physics, from mineralogy, from geology, from psychology, is in reality a complex vibration of quantum fields, a momentary interaction of forces, a process that for a brief moment manages to keep its shape, to hold itself in equilibrium before disintegrating again into dust, a brief chapter in the history of interactions between the elements of the planet, a trace of Neolithic humanity, a weapon used by a gang of kids, an example in a book about time, a metaphor for an ontology, a part of a segmentation of the world that depends more on how our bodies are structured to perceive than on the object of perception—and, gradually, an intricate knot in that cosmic game of mirrors that constitutes reality. The world is not so much made of stones as of fleeting sounds, or of waves moving through the sea. If the world were, however, made of things, what would these things be? The atoms, which we have discovered to be made up in turn of smaller particles? The elementary particles, which, as we have discovered, are nothing other than the ephemeral agitations of a field? The quantum fields, which we have found to be little more than codes of a language with which to speak of interactions and events? We cannot think of the physical world as if it were made of things, of entities. It simply doesn’t work.
What works instead is thinking about the world as a network of events. Simple events, and more complex events that can be disassembled into combinations of simpler ones. A few examples: a war is not a thing, it’s a sequence of events. A storm is not a thing, it’s a collection of occurrences. A cloud above a mountain is not a thing, it is the condensation of humidity in the air that the wind blows over the mountain. A wave is not a thing, it is a movement of water, and the water that forms it is always different. A family is not a thing, it is a collection of relations, occurrences, feelings. And a human being? Of course it’s not a thing; like the cloud above the mountain, it’s a complex process, where food, information, light, words, and so on enter and exit. . . . A knot of knots in a network of social relations, in a network of chemical processes, in a network of emotions exchanged with its own kind.
For a long time, we have tried to understand the world in terms of some primary substance. Perhaps physics, more than any other discipline, has pursued this primary substance. But the more we have studied it, the less the world seems comprehensible in terms of something that is. It seems to be a lot more intelligible in terms of relations between events. (Carlo Rovelli - The order of time)
Supplement to the stone, stick, hand, arm movement:

My personal opinion is that the movement of the stone by the man is a resulting movement. It is a result of an (accidental and non-essential) external occasion (such as the wish of some other person or the partial exposure of something glittering under the stone that is now having a tempting effect) and ultimately (by skipping many intermediate stops) the movement of the blood in the man (the blood as the whole of its chemical activity is, therefore, the last possible stop where we cannot go any further) and gravity in general. As is well known, no organ functions without blood supply. Blood activates and actuates the organs with oxygen. The brain is not excluded from this, so it only has a secondary role, as it could only develop from the blood (the blood contains the élan vital, so to speak). Moreover, an already finished brain without blood circulation would not really be capable of any cognitive performance; it would only be like a huge, abandoned business building. Nowadays one speaks less mystifyingly of blood when one lingers in a similar train of thought than of the so-called "selfish" gene, which constructs the body and its organs like the brain as a survival machine. The theory of the "selfish" gene suggests at least an instrumentalism, the view that the body is the gene's instrument, and that the gene (which is multiplied everywhere in the body) uses the body to carry out its activities. Schopenhauer's statements go in this direction, although he does not yet know anything about "selfish" genes or DNA (Aristotle, by the way, says that the soul is in the heart as a primum mobile and uses the body):
The movement of the blood, like that of the muscle, is also independent and original; it does not even require, like irritability, the influence of the nerve, and is independent of the heart also. This is shown most clearly by the return of the blood through the veins to the heart; for in this case it is not propelled by a vis a tergo, as in arterial circulation; and all the other mechanical explanations also, such as a force of suction of the heart’s right ventricle, are quite inadequate. [Physarum polycephalum can also move forward after all.] 
That the movement of the blood is also independent of the nervous system, at any rate of the cerebral nervous system, is shown by foetuses, which are (according to Müller’s Physiologie) without brain or spinal cord, but yet have blood circulation.


Therefore, just as the blood nourishes all the parts of the body, so, as the primary fluid of the organism, it has produced and formed these parts originally out of itself; and the nourishment of the parts, which admittedly constitutes the principal function of the blood, is only the continuation of that original formation of them.


The course of the arteries, moreover, determines the shape and size of all the limbs; consequently, the whole form of the body is determined by the course of the blood.


[B]lood [...] originally creates and forms the organism, perfects and completes it through growth, and afterwards continues to maintain it both by the regular renewal of all the parts and-by the extraordinary restoration of such as happen to be injured. (Arthur Schopenhauer - The World as Will and Represantion II Chapter XX)
It sounds like I'm taking ideas about what life should be from the vitalism of the 18th and 19th centuries: 
Life, the animate, was supposed to have some sort of vibrant, throbbing quality, some vital essence[.] (Richard Dawkins - THE GREATEST SHOW ON EARTH)
I don't want to be committed. One can understand the "dead" inorganic and chemically elementary in some sense as living, and the "living" organic in some sense as dead, as a rare form of the dead. Panpsychism is an option, and I definitely don't think it's absolutely implausible (people like Philip Goff, Galen Strawson, and also the wife of Sam Harris advocate a type of atheistic and naturalistic panpsychism).

Additional theories about the universe:

The universe as a whole may be more or greater than its parts. If so, this overarching More (the immanent form of the universe) would make the parts possible and activate them (special kind of priority monism). This means that it would not be contingent in any sense and therefore could not be dependent upon the parts as it could not be explained by them. If I let all parts disappear in thought, this More would remain. However, such a thought would only be a matter of pure abstraction, which might never come true and become a reality. Moreover, on a purely theoretical level, I could not speak of a real composition of the universe as a whole, because reality would ultimately be one. For that which is More has no real counterpart or equivalent (because everything else would only be derived from the simple principle and a manifestation of it). On the other hand, I could say that the in-principle somehow illusory parts are perhaps as necessary as the whole or, which is the same, as that More. There would then be no real contingency anywhere. So everything would be basically one and necessarily existing

One could also present the previous approach in a different way so that one could say the following: The last internal, sustaining, and no longer explainable "building block" or "component" of a "composite" would be a simple principle that would, without exception, be present as one and the same in all things. It would ensure the underlying unity of the "parts". In other words, one can explain things by other things and ultimately by that simple principle that lies monistically hidden in all things. This is not theism, because in theism the simple principle is thought externally to all things in the world. It is, if anything, pantheism (Christianity is not compatible with pantheism). Therefore, this is not a bad dualism of two worlds, and certainly not a "substance dualism", but only the duality of two inner links or elements (extended and temporary things and the point-like simple principle) within the whole of our one world.

One should also remember that parts in a holistic whole are not the same as parts in a reductionistic whole. Therefore the former should not be called parts, but rather links or elements of a structure. The holistic whole is not reductionistically dependent on the links or elements, it is rather identical with the outline of the links or elements. Moreover, the links or elements are related in an absolute continuum (infinity) to each other ("tat tvam asi").

The finite differing as regards to content (a specific link or thing) can only occur in the infinite (simple principle as a pure, formal, and original continuum), as only in the formality of the continuum of time and space, that proceeds into infinity (within a limited space or not). This formality is essentially continuous and not discrete. One is mistaken in the opinion that the continuum can only be approached in a reductionist or reductive way by asking for the mere multiplicity of its "components", as mathematicians and even philosophers have done so far. The continuum can only be understood if one asks holistically about the inner unity of this multiplicity, which not even Aristotle or Kant did. This kind of pantheism could be interpreted both idealistically (only in the philosophy of idealism is the freedom of will conceivable) and spinozistically (no room for free will, but compatible with modern physics).

Fox ITK has a different concept of priority monism:
If parts are contingent upon wholes, then that's priority monism- and reverses the direction of dependence the argument relies on. As long as there's a whole for any object (what Jonathan Schaffer suggests would be the cosmos in the maximal sense) then the regress is terminated in that composite which itself is not a further part of some further composite.  
By definition, a whole is not simple so if this is where a regress terminates, it is not what Feser would want, as the fundamentalia is arrived at and in need of no further dependence. This to me seems to beg the question against priority monism. Priority monism argues that the universe is fundamental, not that it can not change in some regards- if its parts change it will change but this does not settle the issue of what is fundamental. I assume some parts AB compose C. Now if C changes there is presumably also a change with regards to AB- perhaps relational- for example, if the organism (the whole) stops taking in oxygen, it’s parts can be affected (cells die). This is true even if whole’s are dependent upon parts, so it seems this fact of whole or part acting such to change the other does not settle the question (in and of itself) of what is fundamental. This is what I take priority monism to be tracking. Now there are arguments for and against it, and the position is not that widely held. But it’s important to note that it could be an answer of sorts to the sorts of worries regresses invoke (that’s actually one of the reasons why Schaffer invokes it, he does actually think the regress is vicious).
In summary, it can be said that the universe as an isolated cosmic system could be ontologically prior to its constituents and thus be regarded as an entity in its own right.

Here is another point of view:
This argument supposes that the universe is a whole, an individual existent, that is different from all the parts of the whole. We are using "U" as the name of this whole. It is an "entailment" argument in the sense that the explanation of why the universe U exists is that its existence is entailed by the existence of its parts, each of which is causally explained in terms of earlier parts. U, the whole of all the parts, is not causally explained by all the parts, since its parts do not cause it to exist. Rather, each part of U is caused to exist by earlier parts of U, and the causally explained existence of all the parts of the whole U logically require or entail the existence of the whole U, and in this sense the existence of the whole U is logically explained by the causally explained existence of its parts. It is a logical truth that if the parts of the whole U are caused to exist, then the whole U also exists. Once the existence of each of the parts is causally explained, the existence of the whole is logically explained, since it is a logical consequence of the existence of the parts of the whole that the whole exists. (Quentin Smith - A Cosmological Argument for a Self-Caused Universe)

Infinite contingencies are also conceivable.

One would then have to assume that they consist of forces or powers, which are discussed in the next section:
No U.S. senator is elected for more than six years at a time, but it does not follow that at one and the same time all senators are up for re-election: they have staggered terms. Similarly, contingent things might well have staggered terms in such a way that at no time there was nothing in existence. If we accept a naive, common-sense notion of time and suppose that by now an infinite time has elapsed, we must conclude, if we embrace this alternative hypothesis to Thomas, that there must have been an infinite number of contingent things; but that, of course, is not at all absurd and actually easier to imagine than Aquinas’ God. (Walter A. Kaufmann - Critique of Religion and Philosophy)
Here's Anthony Kennys' take on it: 
It might be argued that a universe composed of perishable beings might itself be regarded as a necessary being. Certainly, a universe composed of temporal beings might itself be everlasting. But Aquinas, as we have seen, held it impossible that many contingent things might make one necessary being; and though he failed to prove this impossibility the impossibility of an everlasting but contingent universe seems equally unproven. (Kenny, Anthony - Five Ways)
On self-reliant powers (forces):

Every energy concentration or impulse of force is something that is singular, uniform, and active by itself (pure act), even if it has a sphere of power, i.e. an expansion in our empirical eyes. The fact that the force can be measured quantitatively (by strength and intensity) does not change anything. If, for example, I divide a force into two spheres of power, this does not mean that it was composed of parts. It really has been one and centered regarding its effects and operations. Forces are holistic. Although they are divisible, as already mentioned, they do not consist of parts. The parts are only created during the dividing phase (all possible division potentials exist only in the minds of certain philosophers). Prior to that, they did not exist (strictly speaking they are not parts, but now two forces uniform in themselves). Each chemical such as copper oxide is a closed individual form that keeps simple chemical forces bound, or rather, dissolves them into an undifferentiated oneness. These thoughts go back to Philipp Mainländer, who says the following himself:
Every chemical force is divisible; nothing can be objected to this, for experience teaches in this way. But it does not consist of parts before division, it is not an aggregate of parts, for the parts become real only in the division itself. The chemical force is a homogeneous simple force of quite the same intensity, and its divisibility is based on this, i.e. each detached part is, by its nature, not in the slightest different from the whole.
In addition to all this, it should be said that properties of a thing are fundamentally different from parts of a thing. This is also said by Aristotle himself. For a (separated) part of a thing is itself again a thing, on the other hand a property of a thing is absolutely no thing, because a thing can be divided into parts, but by no means also into properties. Because in no way can there be, like parts of a thing, also properties of a thing independently as things.

Galen Strawson draws attention to an important aspect:
[I]f power is the fundamental nature of reality, reality can’t have some other nature distinct from power that is the ground of its power. (Galen Strawson - Nietzsche’s Metaphysics? In: Nietzsche on Mind and Nature edited by Manuel Dries and P. J. E. Kail)
To avoid any monism, which would be a kind of pantheism, one should not say that the universe is force or power, but rather that it is a sum of intertwined forces or powers. There would be no divine (transcendent) unity in, above, or behind these dynamic forces that would coexist with them. The identity of a force would mainly consist in its individuality, which has only a short term existence (it will eventually discharge, and the output is likely to be absorbed or transformed by other individual spheres of force without there being any possibility of generating or destroying energy overall as the law of conservation of energy assumes), but would nevertheless represent a kind of pseudo-process, i.e. always a transition from actuality to actuality (measured on a timepiece)

So with Antony Flew, we can say this:

We therefore conclude, though as always subject to correction rection by further evidence and further argument, that the universe itself is ultimate; and, hence, that whatever science may from time to time hold to be the most fundamental laws of nature must, equally provisionally, be taken as the last words in any series of answers to questions as to why things are as they are. The principles of the world lie themselves `inside' the world. (Antony Flew. God & Philosophy)
Nevertheless, one should not forget the following:
Objects aren’t governed by laws of nature ontologically distinct from them.

There’s no fundamental (real) distinction between objects on the one hand and their propertiedness on the other.

There’s no fundamental (real) distinction between the basic or basal properties of things and the power properties of things.
(Galen Strawson - Nietzsche’s Metaphysics? In: Nietzsche on Mind and Nature edited by Manuel Dries and P. J. E. Kail)
Powers could also be zero-dimensional subjectivities considered as things in themselves. Only in our perception would they appear to have parts (Schopenhauer's idea of the objectivation of the will by the subject).

In my example with strings, one could object that they have a spatial extension and therefore have parts. I would answer the following. Being (spatially) extended (as being a purely continuous, homogeneous, and uniform extension) does not automatically and analytically (logically and necessarily) imply a composition of parts (parthood). In my head, I might be able to think of parts in such a case, but whether these parts are real is another question. The conceived parts may be only subjective (man-made) markings without real content. They would be extrinsic or relational properties at best. Or they only come about when a real division is carried out, as Mainländer suggests (at Planck's "quantum of action" or constant, a division might be practically no longer feasible). Or the question about composition would be just a meaningless and empty question.  

Here is a paraphrase of further thoughts from Mainländer: The division in indefinitum of a given pure spatiality has an innocent side in that a thought thing, which lies only in the head of the person dividing and has no reality, is divided. But its danger is given when the infinite divisibility of mathematical space is transferred, almost iniquitously, to force. Perverse reason takes a finite chemical force, such as a cubic inch of iron, and divides it in thought evermore, and finally wins the conviction that it will never come to an end, even if it wants to divide for trillions of years. But we do, however, first of all, resist the infinite divisibility of forces, because such divisibility can only be asserted if, in the maddest way, the feature of a cognitive faculty (which is, moreover, abused and perverted) is transferred to power or force (perhaps the constantly divided would eventually simply evaporate in gaseous form and finally dissolve into nothing).  

Here is an explanation of space from the perspective of modern physics:
General relativity has taught us that space is not an inert box, but rather something dynamic: a kind of immense, mobile snail-shell in which we are contained – one which can be compressed and twisted. Quantum mechanics, on the other hand, has taught us that every field of this kind is ‘made of quanta’ and has a fine, granular structure. It immediately follows that physical space is also ‘made of quanta’. The central result of loop quantum gravity is indeed that space is not continuous, that it is not infinitely divisible but made up of grains or ‘atoms of space’. These are extremely minute: a billion billion times smaller than the smallest atomic nuclei. The theory describes these ‘atoms of space’ in mathematical form, and provides equations which determine their evolution. They are called ‘loops’, or rings, because they are linked to each other, forming a network of relations which weaves the texture of space, like the rings of a finely woven immense chain mail. Where are these quanta of space? Nowhere. They are not in a space because they are themselves the space. Space is created by the linking of these individual quanta of gravity. Once again the world seems to be less about objects than about interactive relationships. (Rovelli, Carlo. Seven Brief Lessons on Physics) 
About Thomas Aquinas' attitude:
There is little of the true philosophic spirit in Aquinas. He does not, like the Platonic Socrates, set out to follow wherever the argument may lead. He is not engaged in an enquiry, the result of which it is impossible to know in advance. Before he begins to philosophize, he already knows the truth; it is declared in the Catholic faith. If he can find apparently rational arguments for some parts of the faith, so much the better; if he cannot, he need only fall back on revelation. The finding of arguments for a conclusion given in advance is not philosophy, but special pleading. I cannot, therefore, feel that he deserves to be put on a level with the best philosophers either of Greece or of modern times. (Russell, Bertrand - History of Western Philosophy)

Here are also some meaningful remarks from Walter Kaufmann:
Without the aid of Scripture, without building on a prior faith, reason can prove very little, according to Thomas—not nearly as much as we must believe in order to be saved. 
One cannot rely on reason alone to conquer reason that attacks faith. And although the magnificent two-volume edition of Basic Writings of Saint Thomas Aquinas, which is designed to introduce the saint to a large public, breaks off soon after the passages cited here, with Question 7, and although Gilson and Copleston, who try to win friends for the saint, also omit what follows, Question 11, Articles 3 and 4, constitute an integral part of Thomas' system: heretics must be "shut off from the world by death." There is nothing vengeful in Thomas' treatment of this question; he does not raise his voice when he gives reasons to justify the practice of the church in his day. But it would be a grave mistake to suppose that his argument in support of the Inquisition was an incidental all-too-human shortcoming which the saint shared with his age. Not only is it presented in exactly the same logical form as everything that has gone before, but what has gone before cannot be fully understood apart from the question "Whether Heretics Should Be Tolerated?" The reader might suppose mistakenly that Thomas considered his many arguments self-sufficient, when in fact he realized that Aristotle and even Scripture could also be cited by way of proving very different conclusions from his own. He was not as naive as one might suppose he was when one reads some of the books written by his admirers. 
And [Thomas] concludes: "Therefore it is necessary to arrive at a first mover, moved by no other; and this everyone understands to be God."
The last seven words recur with only minor variations at the end of all five arguments. At first, it seems that with these words logical argument has been forsaken and Aquinas merely states what is at best a historic fact. You feel, Aquinas might have added: and if anyone does not understand this to be God, we burn him. 
Here [regarding the Second Way to God] an analysis of the concept of causation, possibly along the lines suggested by Hume or Kant, could cause grave difficulties. Clearly, Aquinas would have burned both Hume and Kant, as well as most other modern philosophers; and he could have adduced—and his followers have adduced—further reasons for accepting his metaphysics rather than Hume's or Kant's philosophy. But for the unaided reason, these arguments are of no avail. (Walter A. Kaufmann - Critique of Religion and Philosophy)
On the First Way:

The First Way is the most important way because the other two have their argumentative power only when the First Way works. That is why Feser is so eager to rescue it. But the First Way, although interesting, is not convincing at all. Richard Swinburne doesn't think much of it either:
See St Thomas Aquinas, Summa Theologiae, Ia2.3. Aquinas’s first way is sometimes said to be a version of the cosmological argument, but it does not count as one on my definition of a cosmological argument, since it argues not from the existence of physical objects, but from change in them. It claims in effect that, given that there are physical objects, change in them is so surprising that we need to invoke God as its source. I cannot see that change in them is so surprising that we need to invoke God as its source. Given the existence of physical objects, it seems to me no more surprising that they should change than that they should remain changeless. Aquinas’s supposition to the contrary arises from the Aristotelian physics that is so closely meshed with his philosophy. (Richard Swinburne – The Existence of God)

Aristotle's principles of nature:

Aristotle mentions two principles in nature: (1) Each movement must be moved by something else. And: (2) Every natural thing has the principle of movement and rest in itself, i.e. it is self-moving. In the realm of the inorganic and the human, Aristotle could not convincingly combine these two principles. If you make self-movement strong, the other principle is less significant. The second principle in the highest sense would be the 'horme' principle, that is, that things have an inherent (spontaneous) striving to move and maintain themselves in a certain way (state) and direction. If the principle (2) is weakened a little, then at least accidental, i.e. temporal or successive causes for movements are necessary. If the principle (2) is very weak, simultaneous and instrumental causes must be assumed for every movement. Self-movement would then be something completely passive. It would be the ability to be moved. In other words, it would be the ability of one thing to let another thing move it. So even here some kind of activity (to let), however weak and small, would have to be given. Aristotle is on the whole ambiguous about self-movement (all the above-mentioned gradations of self-movement seem to occur more or less in his statements). Many popular books on Aristotle praise this principle of self-movement in order to have an alternative to the mechanical and reductionist thinking of modernity. But the stronger the principle (2) is, the less a God must be presupposed. And Aristotle certainly didn't want that.

Aristotle even mentions at one point the two natural principles as mutually exclusive
[E]verything in motion is either moved by itself or by another. (Physics VII, 2) 
Anthony Kenny now shows that when it comes to God, Aristotle thinks little of the principle of self-movement:
The basic principle of Aristotle’s argument is that everything that is in motion is moved by something else. At the beginning of book 7 of the Physics he presents a reductio ad absurdum of the idea of self-movement. A selfmoving object must (a) have parts, in order to be in motion at all; (b) be in motion as a whole, and not just in one of its parts; and (c) originate its own motion. But this is impossible. From (b) it follows that if any part of the body is at rest, the whole of it is at rest. But if the whole body’s being at rest depends upon a part’s being at rest, then the motion of the whole body depends upon the motion of the part; and thus it does not originate its own motion. So that which was supposed to be moved by itself is not moved by itself (Ph. 8. 241b34–242a49).

This argument contains two fallacies. The first is represented in my paraphrase by an equivocation in the expression ‘depends on’. The motion of the whole is logically dependent on the motion of the part, but it is not necessarily causally dependent on it. Moreover, there is a confusion between necessary and suffcient conditions. The part’s being at rest is a suffcient condition for the whole’s being at rest; but from this it follows only that the motion of the part is a necessary condition for the motion of the whole. The argument fails to prove that the motion of the alleged selfmover must have something else, namely the motion of the part, as a causally sufficient condition.
[This argument is vitiated by a double equivocation in the expression ‘sequitur ad’ which I have translated as ‘depends upon’. First, it equivocates between logical and causal dependence, as Sir David Ross points out in his commentary on Physics 242a 38: ‘the motion of the whole logically implies the motion of the part, but is not necessarily causally dependent on it’. (Ross, p. 669). Secondly, it equivocates between being a necessary condition and being a sufficient condition. The part’s being at rest is a sufficient condition for the whole’s being at rest; from this it follows only that the motion of the part is a necessary condition for the motion of the whole, and not that it is a sufficient condition for it. Hence the argument in no way proves that something else, namely the motion of the part, is a causally sufficient condition for the motion of the alleged self-mover. So the reductio ad absurdum fails: it has not been shown that there cannot be a body which can initiate its own movement without external causal concurrence. (Kenny, Anthony - Five Ways)]
There are two ways in which heavy and light bodies owe their natural motions to a moving agent. First, they rise and fall because that is their nature, and so they owe their motion to whatever gave them their nature; they are moved, he says, by their ‘generator’. Thus, when fire heats water, a heavy substance, it turns it into steam, which is light, and being light, naturally rises; and thus the fire is the cause of the natural motion of the steam and can be said to move it. The steam, however, might be prevented from rising by an obstacle, e.g. the lid of a kettle. Someone who lifted the lid would be a different kind of mover, a removens prohibens, which we might call a ‘liberator’ (255b31–256a2)  
If a whole animal moved its whole self, this, [Aristotle] implies, would be as absurd as someone being both the teacher and the learner of the same lesson, or the healer being identical with the person healed (257b5). (But is this so absurd: may not the physician sometimes heal himself?) 
But in the case of an animal, which part is the mover and which the moved? Presumably, the soul and the body.
The example he most often gives—a man using his hands to push a spade to turn a stone—suggests a series of simultaneous movers and moved. We may agree that there must be a first term of any such series if motion is ever to take place: but it is hard to see why this should lead us to a single cosmic unmoved mover, rather than to a multitude of human shakers and movers.
Aristotle himself at one point seems to agree with this objection, and to treat a human digger as a self-mover (256a8).

But Aristotle might, I suppose, respond that a human digger is himself in motion, and therefore must be moved by something else. But his earlier arguments did not show that whatever is in motion is simultaneously being moved by something else: the generators and liberators that were allowed in as causes of motion may have long since ceased to operate, and perhaps ceased to exist, while the motion they cause[d?] is still continuing. (Anthony Kenny – A New History of Western Philosophy)
Here's more relevant stuff from Kenny:
Some Thomists claim that the crucial fact which the First Way seeks to explain is not the tendency which a heavy body has to fall — this, they admit, is something which was given to the heavy body by whatever it was in the past which made it heavy — but rather the current exercise of that tendency in actual motion. Every such potentiality of a creature, they say, needs to be actualized by the immediate action of the Creator. This seems to be a piece of nonsense. To say that something has a tendency to move is precisely to say that unless something interferes, it will move; if it moves therefore, when interference is removed, no further explanation of its motion is called for apart from the tendency and the removal of the interference. This appears to be what Thomas himself thought when he wrote his commentary on Aristotle’s Physics. Commenting on the eighth book he says: ‘Some people inquire why heavy and light objects are moved to their appropriate place. The cause of this is that they have a natural tendency to their places. This is what being light is, to have a tendency to be high up; and this is the meaning of ‘heavy’, namely having a tendency to be low down. So to ask why a heavy body moves downward is simply to ask why it is heavy. And so the very same thing which makes it heavy, causes its downward motion.’ (Kenny, Anthony - Five Ways)

Here are some quotations that show what the inner principle of movement means in natural things:
Aristotle writes that a thing is natural when it has an origin of movement and rest within itself. He explains this rough definition in two respects. First, he also includes growth, shrinkage, and changes in properties under the concept of movement.

A thing moves as itself, if the cause of its movement is solely due to the fact that it is what it is (i.e. in its form). (my translation from Boris Hennig - Eine Verteidigung des typologischen Artbegriffs, A defence of the typological concept of species)
Since the respective form of an object is essential for its identity, and since it turns an inherently unformed matter into an object that belongs to a certain species, such an object can survive not only the change of accidental properties, but also the continuous exchange of its matter or the replacement of certain material parts.

For Aristotle, the soul is not itself a body, but the formal, final, and efficient cause that makes a potentially animated body an actual existing living being, which is why he also attaches great importance to the statement that the soul is the form of a body created in a very specific way.

The soul is the form and actuality of a natural body and gives it certain abilities and functions, which it can only perform in connection with this body. (my translation from Primavesi, Oliver; Rapp, Christof - Aristoteles)
If one does not accept a fundamental (dogmatic) difference between the human form and the mineral form (and everything in between like animals or fungi), this has serious consequences for all Thomism. I myself do not believe in a fundamental difference. 

On metaphysical composition:

One proof of god by Feser is the argument from metaphysical composition. Everything in the world is said to be metaphysically composed of essence and existence and of actuality and potency. This means that we have here a twofold dualism. Or we may say it is a quadrilism. It's a bit funny that Feser who disdains Cartesian dualism or trialism (God as the third substance) has no qualms about his own theory. So God must somehow create these metaphysical parts. Are the parts then, apart from God's omnipotence, indestructible? How does the essence within me differ from the essence within someone else? Is my existence (the metaphysical part of the said metaphysical composition) different from that of something else or even that of God? Must God continue to actualize the actuality part once it has been created? If so, why? Must God permanently sustain potentiality once created? If so, why? How can potentiality and actuality and essence exist in any respect as possible components of a composite, if existence alone is the part to which one can relate the verb exist? So there are many open and strange questions to be asked here. 

To assume that essence, potency and actuality are in themselves non-existent entities that just lack existence is an absurdity. The non-existent cannot form a composition with other non-existing entities. A non-existent entity does not exist in any sense. So it is a nothing, with which you can't do anything in any sense. An entity either exists mentally in a mind (it could also be the mind of God, but that such a mind exists has yet to be proven) or physically in reality or not at all, everything else is a perversion of human thinking. The empty idea of a non-existent entity could exist mentally, if at all. But more is not possible. It obviously makes no sense to say that there are non-existent entities. If we play through that perversion, we can say that the metaphysical composition consists only of the existence part, since the other parts do not exist. If they exist, then the existence part had to create them first or it had to bring them out of the mental existence into the real existence. 

Whether existence is a (real) predicate has been intensively discussed since Kant. Schopenhauer says
that Aristotle pronounces the sentence: ‘since being is not a genus, it is not the essence of anything.’ That means, ‘existence can never belong to essence; being can never belong to the essence of a thing. (Arthur Schopenhauer - Principle of sufficient reason)
It occurred to me that one could distinguish between "something", "real", "being". "Being something" (being causally effective and receptive) makes sense, "being real" (being independent of a mind) makes sense, but "being being" makes no sense, which Aristotle might be right about. Only essences can be said of a being. Predicating being of being would be obviously tautological or meaningless. In the end, it's all a confusing abstract tangle.  

However, a receptive subject must already exist as something or have a trace of existence in order to receive a predicate at all (like that of the alleged existence that is oddly enough already presupposed by the subject for itself). On the one hand, we can say that existence is not a real predicate at all, on the other hand, we can say that there is no real difference between the essence and existence of a mental entity like a concept or between the existence and essence of a real entity like a physical object. Whatever one thinks here, it falls to the disadvantage of the Thomist. 

The argument from metaphysical composition seems completely artificial, invented, contrived, and rigged to create a seemingly solid proof of God (one makes many linguistic fiats to get the desired result). Indeed, the proof has something to offer if one accepts the whole Thomistic framework (this whole necessarily and indispensably includes also, for example, accepting the existence of demons and angels that are among us or at least influence us). Outside this framework, the persuasiveness looks rather bad. One can say that in a nominalistic context, the proof does not make sense at all. Under nominalism, the talk of a real composition of universals makes no sense. Universals are therefore nothing real in their own right. They do not refer to something real, at least not to something that the theist or anyone else hopes for. Just because there are words like essence, existence, potentiality, and actuality does not mean that they denote something. If they do not denote anything, no convincing argument or conclusion can develop from them. 

The first big problem of the proof is that it argues with reified or hypostasized (almost personalized or personified) abstractions. Since man, for example, consists of these heterogeneous abstracta (essence, existence, potency, actuality), there must be something that sticks them together (if it should be wrong to talk about these abstracts in a hypostasizing and reifying way, then the proof of metaphysical composition makes no sense at all). That is, we need a metaphysical glue (a special kind of causality, magical causality) that can only be supplied and applied by something that is not composed, that is, by the Thomistic God. That's all the evidence. One can already say in advance that the abstract terms used, including the glue, cannot be determined or defined without confusion, ambiguity, and begging the question. You don't have to be a great philosopher to suspect this. Moreover, the metaphysical composition needs no God. If Aquinas already says that an accidental causal series can be infinite (a begotten father who is composed begets a son who is also composed and likewise begets a son and so on to infinity in both directions), then there could be an infinite accidental series of metaphysical composites. A metaphysical composite - that was created by a metaphysical composite that was also created by one and so on - would create a new metaphysical composite and this new one would create another and so on. That metaphysical glue could suffice for accidental or generative and linear causality by having to glue the metaphysical parts together only once. If God himself were the glue, then we would clearly be dealing with pantheism.

In the end, it must be said that one only wants to take refuge in highly abstract concepts like the four mentioned to avoid a factual explanation.

You can find a good criticism of Feser's position which says that a metaphysical composite must be held together by God at all times if you go to the following link and look for the following text passage Let’s evaluate Feser’s two central arguments that directly target existential inertia from that paper:

Here is a quotation that also problematizes Feser's ideas:
[E]ven if matter and form have no intrinsic tendency to persist, they might once joined. […] We can allow that matter without form and form without matter are nothing, but go on to say that the matter-form union is perfectly stable. The stability doesn’t have to be completely foreign from the intrinsic natures of matter and form. It’s just that it takes the combination of those natures to sum to inertia. Compare an appropriate pair of right triangles. Neither is square intrinsically, but put them together and they form a square. They give what they didn’t have by pooling their resources. (Paul Audi - Existential Inertia in Philosophic Exchange Volume 48 | Number 1)
Now I come to potentiality. I can think of infinite degrees in which a spatial or qualitative potential of a thing is being actualized. That is, there is an infinite number of ways to actualize something in a thing. So does this thing have an infinite potential which is supposed to be a real part of a whole (for example, I can conceive of infinite levels of intensity of just only one aspect of something)? Why should I not be able to apply mathematical infinity to potency in whatever (qualitative, spatial, or quantitive) respect? From a Thomist point of view, there should be no objection (since potential infinity is an Aristotelian idea), but then we are dealing with the paradox of an infinite reality (at least for the Thomists it is paradoxical and problematic). Because potency must be something real in some sense, otherwise one would not be able to deduce a real God from it (and from other sources). Let's be honest, the potential could only exist like the what-if scenarios. So, only in fantasy.

Potentiality makes no sense unless it is understood as a direction toward something, and so as a (kind of) motion, that is, something that precedes a completed or full actualization, so to speak. Or potentiality could be only something in abstracto, only something for a more detailed man-made description of a man-made aspect of motion (maybe without correspondence with true reality). Or perhaps it is closely related or even identical to final causality. There is a reason to suspect that potentiality is merely another word for final causality. But so far, I had understood final causality as something active and actual. With the Thomists, however, final causality or potentiality (assuming they are identical) seems to be merely a passive directedness (passive directionality)We would thus have as a result a dualism between the one God in actuality and the completely solidified and frozen world in potency (would the world then be plural or one?). This might be the true and strange ontology of the Thomists. By the way, how could a pure and total actuality create potentiality? For by Aristotelian standards, 
a cause cannot give what it does not have[.] (Edward Feser)
Or it was never created, and we have a real eternal dualism. There is also the danger that the Thomist God degenerates into the mere actualizing form of the world. 

Every potentiality must have its regular way of letting itself be actualized (willingly). One can certainly call this an ability and therefore a potentiality, and this potentiality, in turn, may have a similar ability and so on and so forth. The scholastics already said: Materia appetit formam. So matter strives for form. And pure matter is pure potentiality. An actuality must lie in potentiality or an activity must already lie in passivity. 

Galen Strawson makes a good point:
The only way to exist without being potent, without being disposed to have an effect on other existing things, is not to exist! All being is necessarily ‘potential’ being in the original sense: potent being, power-involving being. Power being is categorical being, like all being. Potency entails actuality, reality, and conversely. (Galen Strawson - Nietzsche’s Metaphysics? In: Nietzsche on Mind and Nature edited by Manuel Dries and P. J. E. Kail)
Perhaps there is no real distinction between potency and actuality. Here, perhaps, thinking takes apart boldly and carelessly what really is one

The German philosopher Gerold Prauss also raises a problem of the distinction between actuality (reality) and potentiality or, which is the same thing, possibility:
This becomes obvious, however, when one asserts in what sense we form and use the term for something, and this already in everyday colloquial language. If we form and use a term such as "tree" or "house", it has the meaning that something is a tree or a house only if it is real as a house or as a tree. That means: If it is not real as a house or as a tree, it is not a house and not a tree. To the meaning of "house" or of "tree" belongs therefore the meaning of "real", so that exactly in this sense it is ultimately analytic-tautological to speak of a house or a tree as a real one. And so it goes on to say that it is ultimately analytically contradictory to speak of a house or a tree as a possible one, because that is supposed to mean speaking of each as an unreal one. And in fact, if something is not real as a house or a tree, but only possible, then it is also everything but a house and everything but a tree, as whatever it really is. To distinguish between something as merely possible and something that is also real is therefore without any informative sense, because it is contradictory on the one hand and tautological on the other. (my translation from Gerold Prauss - Continuum and Infinity. A riddle after Aristotle and Kant)

A potential house is undoubtedly not a house, no matter what else might be understood by it. By potential house, we probably mean the real and actual building site, the real and actual building materials, the real and actual construction workers, and so on. I personally find Prauss' argumentation quite convincing. What I want to show is that potentiality is not a fundamental concept, that it does not point to something ontologically fundamental, which the Thomists, on the other hand, assume in the so-called cosmological proofs of God, because otherwise, the proofs wouldn't work. 
Prauss wants to say, that, for example, the distinction between a part that is real or actual and a part that is potential or possible is not an informative distinction because it only distinguishes between the contradictory and the tautological. Either a part is present, but then also as real, or it is not present at all. According to Prauss, the expression "potential part" is misleading, because one thinks that in some sense a part is in fact there. However, there is no part there, instead, there will be something there that is real and actual, but is not a part at all. Here is another translated passage from Prauss, which I have edited a little bit for better understanding:
The meaning of a conceptualization of part as real and part as possible thus ultimately pretends that in each case there is talk of a part, which is not true. What we have here is rather an error which does not occur very rarely and which is not limited to parts: the error of wrong specification. The meaning of this conceptualization gives the impression that "parts" can be specified as alleged genera to be "actual" or "real" and "potential" or "possible" as alleged species, each of which would be a type of part, which is not the case here. For only real ones are parts, possible ones are not parts at all, which is why it must be questioned what the meaning of this concept formation should be. (Gerold Prauss)
A potential part of something is thus not a part. It may be anything (as real) but not a part. Therefore one should always pay attention when the Thomist talks about a potential thing because his language can lead to philosophical wrong tracks. Trick Slattery makes a similar objection or rather correction as Prauss but refers to something different, but not entirely different: 
In regards to acausality, it’s easy to become confused over virtual particles, because they are said to “pop in and out of existence.” “Popping” (or sometimes “jumping”) in and out is quite metaphorical, and so is the word “particle” in “virtual particle.” A virtual particle coming in and out of existence doesn’t imply that it does so without a cause. It simply refers to a disturbance in a field that isn’t a particle. That disturbance comes in and out of existence, much like a ripple in water comes in and out of existence, but it in no way implies that there are these magical particles popping in from nowhere, with no cause directing them, and then just disappearing. (Slattery, 'Trick - Breaking the Free Will Illusion for the Betterment of Humankind)
A virtual particle is not a particle. In German, virtual is synonymous (among other things) with potential.

In order to play with the general concepts of potentiality and actuality, one would at least have to make it clear that potentiality is dependent on actuality, that it represents an aspect of it or, in a sense, lies within it (actuality has to be prioritized). Nothing else would make sense. I might as well say that the actuality of A is a potentiality for (in relation to) the actuality of B. Potentiality would thus be a purely relative concept. The relativity would look like this in the case of forces: the actuality of the force A is in some sense a potentiality in relation, and only in relation, to the actuality of the force B.

That's all abstract twaddle. One must never forget Schopenhauer's instruction: 
I cannot emphasize enough that all abstract concepts are to be checked against intuition [(visual) perception]. (Arthur Schopenhauer - On the Fourfold Root of the Principle of Sufficient Reason)
A good discussion of abstract Thomistic potentiality can be found here: 

And here:

Further on potentiality and actuality:

Both seem to be "real" according to the Thomists. That is, they share the same being (nature, essence), which consists in realness. Thus, they are not completely heterogeneous with respect to each other.

So if the Thomists say that potentiality is real and actuality is also real, then both terms seem to be species terms. The generic or genus term would then be the real.

The question is also what the real is. According to common understanding, it is that which is locatable, has a place, or is extended. To be real, according to philosophical understanding, is to exist independently and outside of a subject or mind. To be real is also a synonym for to be actual. Thus, the real is primarily that which can act upon something (activity), and also that which can be acted upon (passivity)

Maybe potentiality and actuality express only different metaphysical "aggregate states" in analogy to the physical aggregate states like liquid, solid and gaseous and being plasma.

A remotely similar idea exists in the philosophy of physics, where the concept of matter includes physical fields:
As we will see later, fields have energy. They therefore are a form of matter; they can be regarded as the fifth state of matter (solid, liquid, gas, and plasma are the other four states of matter). (Marc Lange - An Introduction to the Philosophy of Physics)  
Physical fields, in turn, can form and move matter (actualize):
Ordinary matter is held together by electric fields, so if those fields are altered by motion, then it is only to be expected that the shape of the matter will be altered. (Wallace, David - Philosophy of Physics: A Very Short Introduction)
Potentiality would then be something like condensed pure energy, which cannot discharge due to some hindrance.

It would be what physics calls potential energy, thus only rest energy in contrast to kinetic energy. The newest physics speaks in particular also of rest mass which is nothing else than concentrated energy in the end.

Actuality would be something like an electromagnetic wave field, which is the constant passing and arising of energy (wave movement). The movement itself would be without any substrate, but it would emanate from the potentiality as "fixed" "material" energy.

So the electromagnetic waves would not be based on oscillations of any substance. They would be spatio-temporal structures which don't need any material carrier, which makes them appear somewhat spooky and ghostly. They can form the potentiality or matter from which they arise spontaneously quite gradually and continuously without discrete jumps, therefore without problems by Zeno's paradox. They can be also influenced by that matter.

The relation between the mental and the body could be thought similarly. The former would arise from the body, which is bundled and bound energy, and can move it within the stream of consciousness or put it into rest as well.

This would be a naturalistic approach. Potentiality is rest mass or quantum stuff.

Actuality and potentiality would be specifications under the genus of the immanent and worldly real par excellence, then also the indispensable existence of God would be endangered and the way to naturalism would be paved:
  • Potentiality as bound and bundled or condensed energy (matter; in humans the body).
  • Actuality as field energy (form; in humans the mentality).
Both must be thought perhaps in such a way that they always appear together and united. But actuality would spontaneously spring from the ontologically prior potentiality. Mentality would appear as a subject based on a highly complex organized body:
[T]he subject would be exactly that which through itself as that completely special type of constant motion would place its body in motion or at rest: already as a cognizing, and thus first and truly as an acting subject. (Gerold Prauss - The Problem of Time in Kant)
The relation between the mental and the body could be thought according to this principle in this way. The former springs from the body as bundled and bound energy and can move it or put it into rest.

(Pure) energy as the real par excellence, "energeia" with its subtypes of rest mass and kinetic field energy.

I have obtained these thoughts on energy from Gerold Prauss (formal cause as formative energy) and partly from Rupert Sheldrake (morphic fields) and Philipp Mainländer (individual immanent powers or forces).

Physicists, at least some according to Prauss, assume that the electromagnetic field energy is a purely continuous and spooky arising and passing away. This could explain movement of a "whole" thing as or in a continuum. 

Matter and form would both be actualities. The former would be already coarsely formed energy and the latter would be forming fine energy necessarily arising from the former.

Potentiality would then only be a fantasy product.

The potential itself seems to have a potential again:
There is a problem, it seems, in ascribing such importance to Aristotle’s influence on Trendelenburg. For when he does comment on Aristotle’s explicit definition of motion, Trendelenburg explicitly rejects it. In Physics III,1 Aristotle had defined motion as “The actualization of what exists potentially, in so far as it exists potentially.” (201a) Trendelenburg took issue with this definition in the Logische Untersuchungen on the grounds that the concepts of actuality and potentiality are less primitive than motion itself, and indeed need to be defined through it (I, 153). Potentiality made no sense, for example, unless it was understood as a direction toward something, and so as a motion. (Frederick C. Beiser - Late German Idealism. Trendelenburg and Lotze)
The alignment in the direction of something must be understood as a kind of movement.

Actuality and potentiality are thus realities. They are possibly special forms of the real: the real potential and the real actual. Maybe they are not heterogeneous to each other. Indeed, they may be consubstantial or of the same nature.

The Thomists say that they can be called real only in an analogous way of speaking which is not very convincing. For it is clear that for Thomists "being real" is clearly reserved for God alone. Cue ens realissimum, though I don't think there can be a meaningful comparative or superlative to "real."

Actuality and potentiality could therefore be mere relations in a causal interaction. Or they merely describe the states of one real and another during such an interaction. 

Why should the actuality of something not at the same time be potentiality in a certain respect. And why should the potentiality of something not be actuality in a certain respect at the same time?

Regardless of what has been said so far, it seems that potentiality has an ontological priority over actuality for Thomists, at least within our world. For example: my potential existence precedes my actual existence, so God can or must actualize me directly or indirectly. The question that immediately follows is: why must this be so? Why should it not be possible the other way around?

The real could be the infinite as a genus. Actuality and potentiality would be species terms of this infinite and therefore of finite kind.

I got the genus idea from Prauss, who wants to avoid a "bad" dualism between our world and the infinite:

Precisely in this, a mathematician like Cantor, for example, who simply equates "human" understanding with mathematical understanding, must despair far too early and in the end again fall prey to a back world [other-world; in German "Hinterwelt", coined by Nietzsche], because all that remains for him to represent is: "What lies above all finite and transfinite is not a 'genus [supremum]'; it is the single, completely individual unity, in which everything is, which embraces everything, the 'absolute', for the human understanding incomprehensible, thus not at all subjected to mathematics, immeasurable, the 'ens simplicissimum', the 'actus purissimus', which is called by many 'God'." For very well the original infinite, as it becomes comprehensible to philosophy as the form of the finite, is the genus as the supreme ("genus supremum"), as which it cannot be something like a backworld to the finite, but must be the center of this finite as such.
One can ultimately connect the concepts of actuality and potentiality with different metaphysical systems. There is no prohibition to do so, provided one wants to use the terms. Thomists are not the right holders of these terms and their philosophical classification and meaning.

Ultimately, God cannot be derived from the concepts of actuality, potentiality and change. 

The proof from the metaphysical composition is based on pure Thomistic, in this case non-Aristotelian (the Aristotelian formal cause is quite powerful in contrast to the Thomistic variant), hylemorphism. Man, like every thing, is said to be composed of form and matter, or actuality and potentiality, or existence and essence. Feser, of course, defines these elements as being nothing in themselves and having no permanence, so that God must constantly assemble and preserve them. Not only is a universal realism assumed here, but also certain definitions of the elements. Feser says that they are all in themselves only abstract and have no efficacy. But why should they not be concrete and efficacious elements in some sense?

If matter has no characteristics as such or is nothing in itself, and the same is true of form, I find it hard to imagine how they should result in anything real at all when combined together:

[I]f neither matter nor form have properties in themselves, then--per Feser's argument--neither can their union/composition. And that's clearly false, since their composition is just the substance itself, and obviously substances have properties in themselves.

Using RM's response against him, and using your comment above, we can construct the following parody argument against Feser:

1. A cause cannot give what it does not have to give.

2. A material substance is a composite of prime matter and substantial form.

3. But prime matter by itself and apart from substantial form is pure potency, and thus has of itself no properties.

5. And substantial form by itself and apart from prime matter is a mere abstraction, and thus of itself also has no properties.

6. So neither prime matter as the material cause of a material substance, nor substantial form as its formal cause, can impart to the material substance that they compose any properties of itself.

7. But there are no other internal principles from which such a substance might derive such properties.

8. So no material substance has properties of itself once it exists. [And this is absurd!] (Joe Schmid: See youtube: the majesty of reason)

If one looks more closely at all mentioned very general terms (which in truth should all have only a narrowly defined field of application, which the Thomist does not pay much attention to), one sees that they have been abstracted only from empirical objects. One has thought things apart (detached) from an empirical object or from subjective mental states, an object, or states that in reality cannot be taken apart. That is, nothing was ever put together metaphysically. 

As soon as one applies those very abstract concepts to the world or translates them into reality, the proof by metaphysical composition no longer has any validity (for it is necessarily bound to the first three concrete ways), as I hope to have shown in many passages of my criticism of Feser.

Even if one takes the metaphysical composition seriously it does not necessarily lead to a classical monotheism. It could just as easily lead to a quasi-thomistic pantheism reminiscent of Hegel, a quasi-thomistic deism, or a quasi-thomistic pandeism in which the world would be a collective or bundle of hypostạtic unions. A quasi-thomistic atheistic metaphysical infinitism would also be conceivable. Then there would be an infinite temporal series of begetting and begotten metaphysical compositions, whose composition would have to be glued together only once and would either remain eternally or would decay after a certain time. A genuine Thomistic God is not compellingly needed in the mentioned cases.

Here is a brief explanation of the pandeism mentioned. According to this, God would have irretrievably transformed himself into a bunch of something like hypostatic unions. He did this in a free act and since then he is no more. So there is no more transcendence. We would then be dealing here with a deified naturalism. 

If Feser's reconstruction of the Thomistic cosmological proof of God in its deepest core amounts to saying that God must always produce the relation of a thing to its properties, and that, for example, in the case of a change of place from A to B, that relation must be produced anew each time, since the properties as spatial coordinates change constantly, we come to problems concerning the diachronic identity of the place-changing substance (to which Joe Schmid draws attention, and concerning the timelessness of God.

If God, figuratively speaking, creates two supposedly heterogeneous parts like the thing and its spatial properties always anew and always holds them so close to each other that he gives the impression that they form a unity, then the reality would only be fake. It would only be like a movie that runs, whose "actors" would be someone else at every moment.

There would possibly be no real diachronic identity in the world, since we would have to deal, so to speak, with a constant prestige effect in creation (the Christopher Nolan film: Tesla's machine, which creates a new magician with every performance)

Furthermore, God Himself would have to be temporal. Because he intends constantly, namely in pure temporality, the connection of the thing with its properties (ontologically preceding, he intends their existence. Potentiality and actual existence would also have to be always new). Thus, the spatial change presupposes a temporal change as absolute coming into being and passing away, otherwise Zeno's paradox with local movements could not be solved from the Thomists' point of view. Alternatively, the change would be more like a flip-book, everything would be essentially erratic. Only the brain would illusorily make a fluid motion out of it. But with it the identity problem would still exist.

The Thomists say that God is nevertheless timeless, only his effects are temporally spread out. But Ryan Mullins draws attention to a difficulty: 

The problem under consideration is not simply that the effects of God are temporally spread about. The problem is that God must be present to each moment of time in order to sustain it. (Ryan Mullins - The End of a Timeless God)
Therefore, God must be called temporal.

If you dwell in such lines of thought, which you probably don't have to in this subject matter, but if you care to, the German idealist philosopher Gerold Prauss does a much better job than the Thomists.

The infinite simple (divine) principle temporalizes itself spontaneously out of itself to an intention of a spatial empirical object as a substance. The different elements like property and thing are all unified by that simple infinite principle manifesting itself into worldly finitudes. Through this manifestation, an identity of the subject as well as the object is secured.

But this would be a monism or pantheism rather than a classical theism and God-world dualism.

Here is Gerold Prauss' view again in other words. More can be found here:

What secures identity in Prauss is the principle of a divine simplicity or point that manifests itself in everything in the world. The divine principle generates the world through self-limitation or self-finitization and gives it unity.

That is, the relationship of the simple principle to the world is that of a manifestation. Thus, I am myself a respective manifestation, and my unified identity is ensured by my innermost building piece, namely the simple divine principle.

Sometimes I have the impression that Thomism is actually a pantheism, but denies it in self-deception and with pure verbalism of empty words.

Bertrand Russel criticizes the idea that essence and existence are identified in God: 

The contentions that God's essence and existence are one and the same, that God is His own goodness, His own power, and so on, suggest a confusion, found in Plato, but supposed to have been avoided by Aristotle, between the manner of being of particulars and the manner of being of universals. God's essence is, one must suppose, of the nature of universals, while His existence is not. It is difficult to state this difficulty satisfactorily, since it occurs within a logic that can no longer be accepted. But it points clearly to some kind of syntactical confusion, without which much of the argumentation about God would lose its plausibility. (Russell, Bertrand: History of Western Philosophy)
William Lane Craig also makes a very good point:
Finally, to say that God’s essence just is his existence seems wholly obscure, since then there is in God’s case no entity that exists; there is just the existing itself without any subject. Things exist; but it is unintelligible to say that exists just exists. (J. P. Moreland and William Lane Craig - Philosophical foundations for a Christian worldview)
Something that is in no way an entity could not have created a world. A created world must also be an indicator that the essence of the Thomist God must be different than "before" (which is not meant temporally) the creation. And when the genuinely real world ceases to be, that God must be also acting differently. Anything else makes no sense to our everyday mind.

Kenny draws attention to a discrepancy regarding time relations between God and the world:
Indeed, the whole concept of a timeless eternity, the whole of which is simultaneous with every part of time, seems to be radically incoherent. For simultaneity as ordinarily understood is a transitive relation. If A happens at the same time as B, and B happens at the same time as C, then A happens at the same time as C. If the BBC programme and the lTV programme both start when Big Ben strikes ten, then they both start at the same time. But, on St. Thomas' view, my typing of this paper is simultaneous with the whole of eternity. Again, on his view, the great fire of Rome is simultaneous with the whole of eternity. Therefore, while I type these very words, Nero fiddles heartlessly on. (ANTHONY KENNY - DIVINE FOREKNOWLEDGE AND HUMAN FREEDOM. In: AQUINAS: A Collection of Critical Essays EDITED BY ANTHONY KENNY)  
About the (for me) incoherent and mysterious Thomist theory of concurrentism or about what theologians rack their brains over:

According to concurrentism, God does act in every action of every creature, so probably also in the act of choosing. Against the occasionalist position, the concurrentist holds that created substances make a purportedly genuine causal contribution, but, against the mere conservationist, they do so only if God cooperates with them contemporaneously as an immediate cause in a certain "general" way which goes beyond conservation and which makes the resulting cooperative action to be in all relevant respects the action of both God and secondary causes. This divine cooperation with genuine secondary causation is called ‘concursus’, ‘general concurrence’, or ‘concourse’. I agree with Mr. Insole on the following:
Even when we have contemplated the parameters of the concurrentist position, I confess it remains difficult to understand how our action being free is compatible with it being part of the same unified action that is determined by God’s. Rather as with divine simplicity, it can feel as if it is being asserted that two hard-to-relate considerations are unifiable, and a name is given to the assertion; but we might worry that the assertion itself has not been explained or defended. (CHRISTOPHER J. INSOLE: Kant and the Creation of Freedom – A Theological Problem) 
I think general concurrence implies the middle ground fallacy. Because the other alternatives are much clearer to understand: occasionalism and mere conservation. It is fairly clear to see what it is they are asserting, and how what they are asserting might be true. So why choose the unclear option. Just because it could compromise the sovereignty of God in one case and increase it too much in the other. That's not good enough for an argument. The Thomist 
merely provides a verbal explanation[he] takes refuge behind a highly abstract concept in order to avoid a factual explanation[.] (Arthur Schopenhauer - On the Fourfold Root of the Principle of Sufficient Reason § 49)
Here the major problems with concurrentism are outlined:
Suarez himself, is able to state so powerfully the problem with concurrentism, when ventriloquizing an argument for occasionalism, the view that ‘created things do nothing, but God brings about everything in their presence’. The ‘principal foundation’ for occasionalism, Suarez explains, is that ‘to whatever extent efficient causality is attributed to the creature, to that extent the divine power of the creator is diminished’: For either God does everything, or He does not do everything; the latter detracts from the divine efficacy, and for this reason we will show below that it is false and erroneous, since it implies that something exists without depending on God. But if God does everything, then I ask again whether He does it immediately and by a power that is sufficient, or only mediately and by a power that is not sufficient. The latter detracts from the divine perfection. But if the former is true, then any other efficient causation is superfluous, since one sufficient and efficacious cause is enough to produce the effect. Another supporter of concurrentism, Freddoso, acknowledges that this is a ‘real challenge’ to the ‘via media between occasionalism and the theory on which God contributes to natural effects only mediately, i.e., by creating and conserving material substances and their powers’: For if God is an immediate active cause of every effect brought about in the realm of pure nature, then nonfree creatures are immediate active causes of natural effects only if some such effects come immediately from both God and creatures. But, the argument goes, it is impossible to give a coherent and theologically orthodox account of how an effect might be brought about directly or immediately by both God and a creature—i.e., an account that does not render one of those alleged causal contributions wholly redundant. The problem of human sin also presents a challenge for thinkers who uphold concurrentist approaches. It seems that the theologian must say that here at least, in the case of sinful human actions, there is an act where God is not acting, but where the human being acts contrary to the will of God. The mere conservationist seems to have less difficulty here: God is responsible only for our existence, but does not act directly in our free actions. Where the concurrentist tradition attempts to deal with this problem, it speaks of sin as a lack, or a defect in the proper created order. As Tanner acknowledges, this ‘simply pushes the question of the origin of sin back to the question of what brought about the first defect’: ‘The question has to stop somewhere since, according to our premises, God does not create a world of sin. But wherever one stops, God’s will would seem to be behind whatever created activity brings sin about.’ After exploring different strategies, Tanner concludes that the theologian ‘can offer no account of how sin actually arises that does not imply that God’s creative will is directly behind such an eventuality’. The implication that Tanner draws from this is not that concurrentism should be abandoned, but rather that we should abandon the attempt to find an explanation for sin: ‘To say that sin is an exception to the premise of God as creator is therefore to say that sin is ultimately without explanation; it is what, by all rights, should not exist in a world that God creates. If a good God is the ultimate explanatory principle according to our picture, is not this inexplicable character of the coming to be of sin what one should expect.’ (CHRISTOPHER J. INSOLE: Kant and the Creation of Freedom – A Theological Problem)
Both man and God perform the choice of sin and the sinful action together. God is anything but passive here. Nor does he simply let the sinful act just happen, for he is actively, immediately, and directly involved in it. So God might be a real collaborator of sin. I do indeed think that there is a problem with the theory of concurrentism in relation to the act of sinning. Alternatively, sin becomes a brute fact, which would be illicit according to the Thomists, since it would violate the principle of sufficient reason. Hence the Thomists are faced with an unpleasant either/or.

Human sin and the omnipotent God of the Thomists cause problems: 
Very briefly, though, at De Malo, 3, 2 Aquinas admits – indeed insists – that God is the cause of what he calls “acts of sin” (actiones peccati): an act of sin is something real, and everything real is from God, so an act of sin is from or caused by God. Thus Aquinas wants to distinguish between the act of sin, which is caused by God, and the sin itself (which is not). For reasons I cannot go into without making an already long section longer still, the distinction Aquinas wants to draw here seems to me obscure and problematic. (Hughes, Christopher. Aquinas on Being, Goodness, and God)
Here are more voices: 
The need to harmonize the moral responsibility of man with God’s justice. The penetrating intelligence of Augustine did not fail to notice a most serious difficulty, which is so hard to remove that, as far as I know, all later philosophers with the exception of three, whom for this reason we shall soon examine more closely, have preferred to steal around it quietly, as if it did not exist. But Augustine utters it with noble sincerity in a quite straightforward fashion right in the introductory words of his books On Free Will: “Tell me, pray, whether God is not the author of evil?” And then more extensively in the second chapter: “But the mind is troubled by the problem: if sins come from the souls which God has created, and those souls are from God, how comes it that sins are not, at a slight remove, to be thrown back upon God?”  To this the interlocutor replies: ”Now you have put clearly what I have been racking my brain to think out.” This highly dubious consideration was taken up again by Luther and brought out with the full force of his eloquence: “But that God must be such that he subjects us to necessity in virtue of his freedom, even natural reason must admit.—If we grant that God is omniscient and omnipotent, then it follows obviously and incontestably that we did not create ourselves, do not live nor do anything through ourselves, but only through his omnipotence.—God’s omniscience and omnipotence are diametrically opposed to the freedom of our will.—All men are inevitably compelled to admit that we become what we are not through our will but through necessity, that we therefore cannot do what we please in virtue of a freedom of will, but rather do what God has foreseen and brings about through inevitable and irrevocable decision and will.” (Schopenhauer, Arthur. Essay on the Freedom of the Will Dover Philosophical Classics)
When we think back to Feser's proof of God from motion, he should have honestly said that both man and God actively move the stone with the stick. This would, of course, have made the proof appear completely abstruse, which is why Feser had cunningly refrained from saying anything about concurrence in the course of the argument. 

On divine conservation:

According to Feser, the world is not self-subsistent. On the other hand, the world is not supposed to be a part of God either, it is supposed to be, so to speak, something that exists vis-à-vis (facing or opposite) him. This means that we have a God-world dualism in the Thomistic doctrine. Feser hates the body-mind dualism, but with the God-world dualism, he apparently has no issue. Be that as it may, in order not to understand the world as a part of God, one must understand it as a kind of substance (and not as an accident)

Yet God is said to be indispensable for the world. What's the meaning of this? We need to do a thought experiment and think away God (for the Thomist per impossibile) and see what happens. According to Thomism, the world should disappear at exactly the same instant as God. But why would that be? It sounds as if the world is completely stuck to God, so strongly stuck that it might be a part of him. One would have to assume that if the world were some kind of substance, it would take some time for it to disappear. This could also happen in a billionth of a nanosecond. The suspicion is that the world is only nominally not a component of God.

As I understand Thomism, God sustains the already created world seamlessly and uninterruptedly in the sense of its absolute coming into being and passing away. So we can say that God's act of sustaining is basically an act of (re-)creating. There is no time span between the moment of creation of the created thing and the moment of its passing, i.e. there is no point in or during the oscillating process of creation where things that are supposed to exist at a certain point in time would not exist if we look at the whole timeline from our human perspective. So the table in front of me fades away and comes into being and fades away again and comes into being again and so on in an absolute sense, that is, without any gaps in time. So the table does not make time jumps but fills a true time continuum. 

Even if the Thomist God is supposed to be atemporal, the completely dependent Thomist world is anchored in Thomist presentism and is therefore in a constant state of coming into being and passing away, even if this happens in an absolute sense (continuously, non-discretely). So God creates something that cannot continue to exist and remain by itself even for the shortest conceivable moment. Can't he just do it differently or is he doing it on purpose? Is he even building a (divine) self-destruct mechanism into the world? When I buy a TV that needs constant maintenance by a person or a machine, then it is definitely of lower quality than one that requires only very rarely maintenance. Does God lack omnipotence or all-goodness when he constantly creates and sustains us in poorer quality? Or does he lack omniscience, because if there was nothing more to do, he would be bored? He would then have no preoccupation with an all-knowledge (my way of speaking can be understood, if you will, merely analogous)?

It seems strange to me that many can only think of the world that exists in motion and in time and space if it is backed by a God who is absolutely at rest (but oddly still fully actual), timeless and spaceless. So the world is supposed to be understandable only by its absolute opposite? I have my reasonable doubts about that.

The Thomistic cosmological proof of God depends on a certain model of God, according to which we are in causal relation to God, but God is in none to us:

Aquinas’ five ways depend on God’s causal activity. If God is not really in a causal relation with the universe, but only in our minds, natural theology faces a serious challenge. The atheist will be happy to say that the universe’s causal dependence upon God exists in the minds of believers only. The Christian cannot be sanguine about this. Many of the arguments from natural theology rest upon the notion that God is causally related to the universe. It is not clear how one might construct a cosmological argument for the existence of God that includes a premise expressing that God only stands in a relation of reason to the universe. (R. T. MULLINS - The End of the Timeless God)
William Lane Craig also remarks on the matter:

The question, then, is whether our predicating of God at the moment of creation the relational property of sustaining the world is merely conceptual or ascribes a real property to Him. "Sustaining" clearly describes a relation which is founded on something's intrinsic properties concerning its causal activity, and therefore sustaining the world ought to be regarded as a real property acquired by God at the moment of creation. I must confess that I find Aquinas's position, that this property is not really possessed by God, but that the relevant real, relational property is being sustained by God, which is possessed by the world, to be quite incredible. If at the moment of creation the world begins to exist with the relational property being sustained by God, then how could God fail to acquire at that very moment the relational property sustaining the world?

The universe's dependence upon God rather than vice versa seems as little reason for denying to God the real relational property of sustaining the cosmos as the dependence of imagined scenes in the mind's eye of the artist or day dreamer would be for denying that such persons have a real relation to the products of their imagination.

If the relation of some cause to its effect is unreal, then the cause has in particular no causal relation to its effect ; that is to say, the cause is not a cause, which is self-contradictory. All we can say in such a case is that the effect is really related to another object or event as the effect of said object or event. In truth there is no real cause in such a case, only a real effect. But it seems unintelligible, if not contradictory, to say that one can have real effects without real causes. Yet this is precisely what Aquinas affirms with respect to God and the world. Words like "First Cause" and "Creator" are only extrinsic denominations applied to God, that is, predicates which do not correspond to any real property but which are appropriate in virtue of real properties in creatures.

Even if we adopt the Thomist view that causation takes place entirely in the effect, not in the cause, that only underscores the reality of God's causal relation to the world, since the world is admitted to be really related to God as effect to cause, to be really caused by God, which is all that there is to causality ; nothing more needs to be added ex parte Dei for Him to be the cause of the world. Yet Thomism denies that God is literally the cause of the world, though the world is the effect of God— which seems contradictory or meaningless. (William Lane Craig - Timelessness, Creation, and God’s Real Relation to the World)

Why in general proofs of God do not work:

We cannot demonstrate the idea of the absolute or unconditioned for the simple reason that it is the basic principle behind all knowledge, and first principles are beyond demonstration. (Frederick C. Beiser - Late German Idealism Trendelenburg and Lotze)

A refutation of the proof of God's existence, however ingenious, is superfluous, for it is part of the idea of a supreme being that it cannot be further demonstrated. (OTTO WEININGER - ON LAST THINGS)

The desire to demonstrate the idea of the good-and-the-true, the existence of a supremely essential value and a supremely perfect being, the existence of God, is practically a contradictio in adjecto. It lies in the very concept of God that it cannot be proven, but only believed. Thus there is no higher tribunal before which logic and ethics have to stand and defend themselves; I can give no further foundation for these two laws. (OTTO WEININGER - ON LAST THINGS)

To recall just one key point, in classical European times and in India much the same arguments were adduced in support of doctrines quite different from realistic monotheism. The argument from design has been advanced in the cause of pantheism. So even if in some form or other it should turn out to be valid, what would it prove? We are not entitled to be sure that it would prove the existence of the God of the realists. (Cupitt, Don. Taking Leave of God)
Proofs of God have something tragic about them. They can be like a beautiful and brilliant shot on a goal in soccer, which nevertheless misses by a very narrow margin.

One can only express the following then: 

Close, but no cigar!

Near enough is not good enough.

All Five Ways criticism:

Anthony Kenny - The Five Ways

Walter A. Kaufmann - Critique of Religion and Philosophy

Lubor Velecky - The Five Ways. In: The Monist 58 (1):36-51 (1974)

Lubor Velecky - Aquinas' Five Arguments in the Summa Theologiae 1a 2, 3 (A thesis of the book: Thomas did not want to prove the existence of God, which he considered principally unknowable)

First Way criticism:

George A. Blair – Another Look at St. Thomas' "First Way"


Graham Oppy – On stage one of Feser's ‘Aristotelian proof’. Religious Studies, 1-12.

Richard Geenen and Roger Hunt: The Prime Mover Removed: A Contemporary Critique of Aquinas' Prime Mover Argument. In: Revisiting Aquinas’ Proofs for the Existence of God.

William L. Rowe - The Cosmological Argument

Scott Macdonald - Aquinas’s Parasitic Cosmological Argument

Second Way criticism:

Graham Oppy – The Best Argument Against God

Jordan Howard Sobel – Logic and Theism

Herbert Roseman - The Irrelevance of Aquinas' Uncaused Cause Argument. In: Revisiting Aquinas’ Proofs for the Existence of God.

Third Way criticism:

John Leslie Mackie - The Miracle of Theism

Jonathan Bennett - Kant's Dialectic

Graham Oppy - Arguing about Gods.

Michael Martin - Atheism

Edward Moad - Problems with Aquinas' Third Way. In Revisiting Aquinas’ Proofs for the Existence of God.

Here you can find internet critiques of Feser's work: (not anti-Thomist, very pro-Tradcat, but anti-Feser)

Miscellaneous reading recommendations:

Christianity's Criminal History by Karlheinz Deschner (an abridged translation of volumes 1-3):

Matthew S. Mccormick - Atheism And The Case Against Christ 

Rondo Keele: Ockham Explained – From Razor to Rebellion

It's about the great nominalist Ockham. The book is clearly written and very informative. It is a very good alternation to Feser's books.

Critical books about Aquinas:

Anthony Kenny - Aquinas on Being

Anthony Kenny - Aquinas on Mind

Criticism of hylomorphism: 

Antonella Corradin - Hylomorphism - a Critical Analysis

Gordon P. Barnes - The Paradoxes of Hylomorphism. In: The Review of Metaphysics, Vol. 56, No. 3 (Mar., 2003), pp. 501-523

Recommendable atheism books as an entry into the subject: 

George H. Smith - Atheism. The Case Against God (this book devotes much attention to Thomist ideas)

David Ramsay Steele - Atheism Explained From Folly to Philosophy

Antony Flew - God & Philosophy (somewhat more demanding, but Thomistic thoughts are approached)

A very good Aristotle introduction, which is also critical: 

J. L. Ackrill - Aristotle the Philosopher

This is an entertaining polemic against Aristotle:

Fritz Mauthner - Aristotle 

Feser criticism in a nutshell (short version)

I criticize here, with the help of many critical quotations from intelligent thinkers, two important theses of Catholic Thomistic philosophy...