"The perverted faculty argument says that the only moral use of the sexual faculty is in its non-contracepted heterosexual use between married spouses. Any other use of the faculty is contrary to its purpose and is thus ‘perverted’."
https://www.faith.org.uk/article/march-april-2006-sexual-morality-the-perverted-faculty-argument
"[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)
Two examples:
"Thomas's theory has implications today for artificial insemination, which was forbidden in 1987 by the Vatican Congregation for the Faith: "Homologous artificial insemination (italics mine) within marriage cannot be allowed." There is one exception, however: Semen can be obtained from intercourse by means of a condom, if this condom is perforated, so that the form of a natural act of generation remains intact, and no impermissible mode of contraception occurs. The conjugal act must take place as if it were leading to procreation, as if it were possible for conception to take place through the holes in condom (cf. Publik-Forum, May 29, 1987, p. 8). And only by this roundabout path, by an infertile conjugal act proceeding as if it were fertile, can fertility be helped along. The supposedly natural act has become the first commandment and it has kept that status even when its original goal, as prescribed by the Church, procreation, cannot be reached at all, and when obtaining semen through masturbation would be just as good a method, or a better one, because it is less complicated. But masturbation still ranks with the most serious, unnatural sins of contraception, even here when it is precisely being used to make conception possible. The standardized procedure has become more important than the goal, namely procreation. What is "natural" is determined by old traditions, and such traditions are carefully protected by old male celibates." (Uta Ranke-Heinemann - Eunuchs for the Kingdom of Heaven: Women, Sexuality, and the Catholic Church)
And:
And:
Natural family planning (NFP), which the Church Fathers would not have allowed, is now permitted as a contraceptive among Catholics. The condom remains sinful. But the intention of a couple using NFP is exactly the same as that of a couple using a condom. The Protestants therefore take the logical view that, in principle, the use of conception-free days is not ethically higher than the use of mechanical means. A God who makes a moral difference between the two couples must be a fastidious, small-minded God, especially since the Pearl Index shows that NFP is even more effective and safer than condoms.
"Even if one could exhaustively describe the elements of our nature, the claim that we are morally obliged to act in accord with them, or to prefer “natural” uses to “unnatural,” could be made only as something additional and adventitious to the whole ensemble of facts that this description would comprise. Otherwise we could not see it as a moral good at all, but only as a negotiable feature of private taste. The assumption that the natural and moral orders are connected to one another in any but a purely pragmatic way must be of its nature antecedent to our experience of the world. I know of many stout defenders of natural law who are quick to dismiss Hume’s argument, but who — when pressed to explain themselves — can do no better than to resort to a purely conditional argument: ifone is (for instance) to live a fully human life, one must then . . . (etc.). But, in supplementing a dubious “is” with a negotiable “if,” one certainly cannot arrive at a morally categorical “ought.” (David Bentley Hart - Is, Ought, and Nature’s Laws. In: A Splendid Wickedness and Other Essays)
"The most gallant of Feser’s non sequiturs is his claim that, because reason necessarily seeks the good, there exists no gap into which any Humean distinction between facts and values can insinuate itself. But obviously the gap lies in the dynamic interval between (in the terms of Maximus the Confessor) the “natural” and “gnomic” wills. The venerable principle that the natural will is a pure ecstasy toward the good means that, at the level of gnomic deliberation, whatever we will we desire as the good, but not that philosophical theory can by itself prove which facts imply which values, or that the good must naturally be understood as an incumbent “ought” rather than a compelling “I want.” Feser asserts that “purely philosophical arguments” can establish “objective true moral conclusions.” And yet, curiously enough, they never, ever have. That is a bedtime story told to conjure away the night’s goblins, like the Leibnizian fable of the best possible world or the philosophe’s fairy tale about the plain dictates of reason." (David Bentley Hart - Nature Loves to Hide. In: A Splendid Wickedness and Other Essays)
"Feser claims that he does not have an “is-ought” problem. Maybe so, but he has merely replaced it with a “natures’s End - ought” problem that is equally tenacious. He still faces the question of “So nature intends that I X. But why should I X?” Seems to me he has gained nothing from that move." (Some internet commentator)
You can derive a practical 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)
"To get an absolute command (or ‘categorical imperative’, as we shall see later) you have to presuppose someone who gives that command. Within the natural law theory, as it has developed since the time of Aquinas, that ‘someone’ is God. This gives its moral pronouncements an authority that may not be justified by the logic on which the argument is based." (Thompson, Mel. Understand Ethics: Teach Yourself: Making Sense of the Morals of Everyday Living)
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)
There is also another normativity from which a pressure to act emanates, which presupposes one's own personal will. I'll give an example: I want to be home at ten o'clock in the evening, so I must (normative must or have to) take the bus at half past nine.
So, if you want y to happen, then you "must" do x, provided you really want to. There must be a strong interest in what is wanted or willed and not just a desire or wish.
However, this normative must would also be incompatible with natural law, since it depends on my personal will. Any normativity in the logical and practical sense tends to be in tension with the ethics of natural law.
"In Eastern philosophy, the idea of karma – that actions have consequences that cumulatively influence the future – relates the state of the world to moral choices. But this gives only a ‘hypothetical’ command (in other words, one that says ‘If you want to achieve X, then you must do Y’), not an absolute moral command." (Thompson, Mel. Understand Ethics: Teach Yourself: Making Sense of the Morals of Everyday Living)
If I already believe in the Catholic hell, it would work. I have to obey such and such rules of the Church because I don't want to go to the hell I already believe in from the beginning. If the belief in the Church (together with her specific idea that the nature of man is so and so and not otherwise) is absent, that normativity no longer exists.
Something else to consider:
"Elective priorities. Assume, however, that we can establish the existence of a moral imperative implicit in the orderliness of the world, as perceived by a rational will that, for itself, must seek the good: Does that assure that we can prove what hierarchy of values follows from this, or how we should calculate the relative preponderance of diverse moral ends? Yes, we may all agree that murder is worse than rudeness; but, beyond the most rudimentary level of ethical deliberation, pure logic proves insufficient as a guide to which ends truly command our primary obedience, and our arguments become ever more dependent upon prior evaluations and preferences that, as far as philosophy can discern, are culturally or psychologically contingent. Consistent natural law cases can be made for or against slavery, for example, or for or against capital punishment, depending on which values one has privileged at a level too elementary for philosophy to adjudicate. At some crucial point, natural law argument, pressed to disclose its principles, dissolves into sheer assertion." (David Bentley Hart - Is, Ought, and Nature’s Laws. In: A Splendid Wickedness and Other Essays)
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)
And why, according to the church, we supposedly have the bodily functions we do, has to do with their idea of the Eden period of Adam and Eve:
"It might help to read Aquinas and Augustine's take on progeneration in the Garden of Eden to understand why, historically, the sexual members have such specific functions.
The predominant view of the time was that either there would have been no procreation, or procreation would have occurred through some divine means. This because sexuality is bound up with lust, and lust is naughty. Aquinas and Augustine argue against the view by claiming that sex would have recurred without stirring the loins through lust." (A reddit view of a user named Quidfacis_)
"If the whole world is in a state of constant change; if galaxies are moving outwards towards an unknown future; if stars are born and die, and planets spinning around them are vulnerable to their death and many other cosmic accidents; if life on planet Earth is a recent phenomenon and subject to a process of evolution – how can the purpose or goal of anything be fixed?
The natural law approach is based on the idea that reason can interpret the essence, purpose and ‘final cause’ of things. We need to consider whether this is compatible with a world viewed from the perspective of evolution and change.
Is morality the result of deliberately going against our basic instincts, as suggested by Richard Dawkins at the end of The Selfish Gene: ‘We alone on earth can rebel against the tyranny of the selfish replicators’? Or is some sense of morality genetically programmed into us? Research on the behaviour of apes suggests that there may be the basics of morality – in the attitude of groups to individuals, and the support given by one individual ape to another. So, for example, animals that fight can ‘make up’ afterwards. Is this programmed into them in order to help the species survive in a competitive environment?" (Thompson, Mel. Understand Ethics: Teach Yourself: Making Sense of the Morals of Everyday Living)
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 possible and potential 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, the more right-wing leaning evolutionary psychology and the more left-wing leaning anthropology deal with this topic), 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.
"Even if final causality in nature is demonstrable, does it yield moral knowledge if there is no clear moral analogy between natural ends and the proper objects of human motive? For Thomas Aquinas, only a moral disorder can make one claim ignorance of the reality of the God who, as the source of one’s being, is supremely worthy of love. True in principle, of course. Even so, the “failure” to find a moral dimension in one’s intrinsic ontological contingency may not be entirely culpable. Our modern narrative of nature is of an order shaped by immense ages of monstrous violence: mass extinctions, the cruel profligacy of an algorithmic logic that squanders ten thousand lives to fashion a single durable type, an evolutionary process that advances not despite, but because of, disease, warfare, predation, famine, and so on. And the majestic order thus forged? One of elemental caprice, natural calamity, the mercilessness of chance — injustice thrives, disaster befalls the innocent, and children suffer. Why, our deracinated modern might ask, should we believe that nature’s organizing finality, given the kinds of efficient causes it prompts into action, has moral implications that command imitation, obedience, or (most unlikely of all) love?" (David Bentley Hart - Is, Ought, and Nature’s Laws. In: A Splendid Wickedness and Other Essays)
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)
And:
"[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)
"Our organs are not for anything, and they have no function or purpose: they do what they do, well or ill. Still less does the human body have a purpose or function; it is not for anything. That, of course, is one of the conclusions to be drawn from evolutionary theory.
[…]
In any case, even if we could say unequivocally what the purpose of any given organ is, we cannot conclude that we ought to use it for that purpose, still less that we ought to use it only for that purpose. That just does not follow. If our hands had the purpose of manipulating objects, it would not follow from that that we ought to use them for that or that we ought not to use them for other things.
[…]
If the sexual organs are for reproduction, it does not follow that they ought to be used for this purpose, not even if we grant that they may or even ought also to be used for other purposes. This no more follows than it follows from the fact (if it is a fact) that human teeth and digestive system are for the consumption of animal flesh (amongst other things) that we ought to eat meat. You cannot refute vegetarianism so easily." (Christopher Hamilton - Alexander Pruss on love and the meaningfulness of sex)
Even if one would admit teleology in nature, one could say that it is merely a necessary condition. It alone does not make natural law ethics possible, and the other necessary conditions can be questioned.
And even if one assumes that teleology is the sufficient condition and also recognizes its validity, then one could still argue eternally about what it now consists of exactly and in detail with the human being.
It is important to mention that for the Thomists, natural things and processes have only one purpose or one that is primary. However, this is pure dogma.
It goes back to Aristotle, who is generally not free of dogmas. His thesis that the species of living things are eternally constant in a certain sense is a dogma that has long dominated the thinking of biologists. It is precisely this dogma that entails the other, which is relevant in natural law ethics. The evolutionary approach, on the other hand, assumes the great importance of the habitat context for the living beings and their abilities.
Moreover, the dogma seems to violate an Aristotelian principle: Namely, it is Aristotle's thesis that the foundational structure in the products of human manufacture is quite the same as in natural things. Art imitates nature is his famous formula for this. It is familiar to us today mainly in limited application: as an antiquated maxim of the fine arts. For Aristotle, however, the scope of the sentence extends to all kinds of human achievements, i.e., to 'art' in the broadest sense.
The natural faculties of man may well be analogous to a hammer:
"A hammer my have been designed to pound nails, and it may perform that particular job beg. But it is not sinful to employ a hammer to crack nuts ff I have no other more suitable toot immediately available. The hammer, being a relatively versatile tool, may be employed in a number of ways. It has no one "proper" or "natural" function." (http://faculty.cbu.ca/sstewart/sexlove/leiser.htm)
After all, according to Ackrill, Aristotles admits that an organ can have two essential purposes, as in the case of the elephant trunk:
"In the following discussion of the elephant's trunk notice the reference to the animal's environment: since he lives in swamps he has to have such-and-such if he is to be able to breath and feed. This is very close to the evolutionist's way of speaking: unless he had means of breathing and feeding in swamps he would not have survived in swamps. Notice also in this example the idea that a part essential for one purpose may also serve a second purpose." (J. L. Ackrill – Aristotle the Philosopher)
Ackrill then gives another example of Aristotle, of which he says:
"Here is another case of one organ with two jobs, but here one job is of a higher order than the other[.]" (J. L. Ackrill – Aristotle the Philosopher)
It is clear that Ackrill understands Aristotle to mean that a natural thing can actually have two different primary, essential functions depending on the context or environment. Thus, Aristotle would contradict his own established dogma.
It should not be controversial that an organ can be given with two tasks of equally high order. If this can be true for organs, why not also for all natural faculties?
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)
"Feser’s argument about sexual ethics makes the mistake of beginning with the ends of one bodily system (the reproductive system) and presuming them to be ends of the person as a whole." (Melissa Moschella - Old Natural Law Theory, Marriage, and Sexual 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)
And:
"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)
And:
"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)
"One might argue that the presence of sexual organs in a human being implies that he or she is designed for sexual activity and the conception of children – in which case, celibacy is as unnatural as homosexuality, since it is a denial of the complete natural function of procreation. If this is established, then it is illogical to accept a celibate partnership between those who are sexually attracted.
Some people are naturally attracted by members of the same sex. They experience their feelings as completely natural. Any difficulties that arise are the result of social conditioning, not nature.
Sexuality can be said to achieve three ends: 1. physical pleasure 2. the deepening of a relationship 3. the conception of children Only the third end is precluded by homosexual relationships. But is not the search for pleasure and for deep relationships as natural as the conception of children? If a marriage is known to be infertile, are heterosexual acts between its partners therefore immoral simply because conception is impossible
Marriage is a social function, and promiscuity can be practised equally by homosexuals and heterosexuals. The fact that homosexual couples cannot marry does not preclude deep and permanent relationships.
If a homosexual couple form a stable relationship, they may be able to offer children a home that is, at the very least, as valuable to their upbringing as one in which there is either a single parent, or a heterosexual couple with a bad relationship. Hence, it would seem illogical to discriminate in this matter.
In pointing out some of the ways in which the ‘natural law’ view of the homosexual couple’s situation might be challenged, it is not intended to undermine the principle of natural law as such, but to show that there are some areas of morality – particularly where relationships are concerned – where it is difficult to consider morality mainly in terms of specific actions." (Thompson, Mel. Understand Ethics: Teach Yourself: Making Sense of the Morals of Everyday Living)
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)
However:
"[T]he intention alone decides on the worth or unworth of the deed, which is why the same deed, according to its intention, can be reprehensible or praiseworthy." (ARTHUR SCHOPENHAUER - The Two Fundamental Problems of Ethics)
"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)
"Our sexual pair bonding, like our sexual activity, is not limited to reproduction. [...] Even in our closest evolutionary relatives, the apes, it is only recently that we have come to realize that sexual behavior is common, not always related to reproduction, and complicated." (Agustín Fuentes - Race, Monogamy, and Other Lies They Told You)
"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)
"How do you decide what is ‘natural’? Science bases its ‘laws of nature’ on observation, and they claim to be no more than an interpretation of the best available evidence. If something is observed that does not fit in with an established law, then either the observation is inaccurate, or another (as yet unknown) law has unexpectedly come into operation. Our understanding of the way in which nature works is therefore constantly being modified.
If this also applies to ‘natural law’ as an ethical theory, then we cannot establish fixed criteria for right and wrong – which was the aim of Aquinas and others who followed this line of thought – because our concept of what is natural, and therefore of ‘final causes’, will always be open to modification.
It is natural for someone who is seriously ill to die. Does that mean that one should not interfere with the natural course of a disease by giving medicine?
In the natural world, the strongest animals often mate with as many sexual partners as they can, fighting off weaker rivals. Should there be selective breeding among humans? Is monogamy unnatural?
These examples suggest that there is no easy way to establish the ‘final cause’ that will enable us to say with certainty that we know exactly what every thing or action is for, or what part it has to play in an overall purposeful scheme of the universe." (Thompson, Mel. Understand Ethics: Teach Yourself: Making Sense of the Morals of Everyday Living)
"The relief of sexual tension, practicing safe sex, greater awareness of one’s sexual preferences, alleviating sexual disfunction, marital satisfaction, and increased self-esteem are all genuine human needs in the human life-form, none of which (except perhaps the first) are needs in other species of animal. These needs indicate some of the ways in which human sexual activity, like human eating, is inextricably bound up with the various physical, psychological, social, and cultural features of the human life-form that make the role of human sexual activity enormously different from the role sexual activity plays in other species. These needs also point more generally to why some intrinsically nonprocreative human sexual activity can contribute to human flourishing: given the human life-form, sex for human beings is not merely for reproduction." (CHRISTOPHER ARROYO - Natural Goodness, Sex, and the Perverted Faculty Argument)
"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)
"Our sexual pair bonding, like our sexual activity, is not limited to reproduction. [...] Even in our closest evolutionary relatives, the apes, it is only recently that we have come to realize that sexual behavior is common, not always related to reproduction, and complicated." (Agustín Fuentes - Race, Monogamy, and Other Lies They Told You)
"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)
"How do you decide what is ‘natural’? Science bases its ‘laws of nature’ on observation, and they claim to be no more than an interpretation of the best available evidence. If something is observed that does not fit in with an established law, then either the observation is inaccurate, or another (as yet unknown) law has unexpectedly come into operation. Our understanding of the way in which nature works is therefore constantly being modified.
If this also applies to ‘natural law’ as an ethical theory, then we cannot establish fixed criteria for right and wrong – which was the aim of Aquinas and others who followed this line of thought – because our concept of what is natural, and therefore of ‘final causes’, will always be open to modification.
It is natural for someone who is seriously ill to die. Does that mean that one should not interfere with the natural course of a disease by giving medicine?
In the natural world, the strongest animals often mate with as many sexual partners as they can, fighting off weaker rivals. Should there be selective breeding among humans? Is monogamy unnatural?
These examples suggest that there is no easy way to establish the ‘final cause’ that will enable us to say with certainty that we know exactly what every thing or action is for, or what part it has to play in an overall purposeful scheme of the universe." (Thompson, Mel. Understand Ethics: Teach Yourself: Making Sense of the Morals of Everyday Living)
"The relief of sexual tension, practicing safe sex, greater awareness of one’s sexual preferences, alleviating sexual disfunction, marital satisfaction, and increased self-esteem are all genuine human needs in the human life-form, none of which (except perhaps the first) are needs in other species of animal. These needs indicate some of the ways in which human sexual activity, like human eating, is inextricably bound up with the various physical, psychological, social, and cultural features of the human life-form that make the role of human sexual activity enormously different from the role sexual activity plays in other species. These needs also point more generally to why some intrinsically nonprocreative human sexual activity can contribute to human flourishing: given the human life-form, sex for human beings is not merely for reproduction." (CHRISTOPHER ARROYO - Natural Goodness, Sex, and the Perverted Faculty Argument)
"[...] Feser’s understanding of the natural ends of sexual activity fails to grasp adequately what is unique about the human life form and its corresponding natural good." (CHRISTOPHER ARROYO - Natural Goodness, Sex, and the Perverted Faculty Argument)
"Critics object that it needn’t be wrong to use organs for something other than their primary biological purpose; for example, there’s nothing wrong in using our feet to kick a football. So it needn’t be wrong to use sex organs for something other than their reproductive functions." (Harry J. Gensler - Ethics: A Contemporary Introduction, Chapter 13)
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 through 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. Even though chewing gum without any nutritional value is cheating my stomach, which is expecting real food; even though my chewing motion is going nowhere (and is proving to be futile) and thus unnecessarily straining my chewing muscles; even though something that cannot be chewed into small pieces and digested should be spat out immediately and should not be kept in the mouth; even though I might have the provocative attitude and intention of demonstratively perverting my food intake system while chewing, chewing gum is morally neutral in itself.
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.
“Presumably, the natural function of the ambulatory system is locomotion. Does not one who walks on a treadmill use this system in a way contrary to its natural function? Walking on a treadmill seems a rather precise parallel to having sex with a condom, for it involves performing the very act ofwalking while ensuring that its natural result, movement from one place to anothis does not occur. Or consider the respiratory faculty. Presumably, its natural function is to deliver oxygen to the bloodstream. People (or boys, at any rate) often enjoy inhaling helium because of the way it makes their voices absurdly high-pitched. Is this an unnatural use of the respiratory faculty? One might answer that it is not, because on the next breath they can always go back to inhaling normal air. But of course the same can be said of masturbation; it too uses a natural faculty for something other than its natural end without in any way preventing that faculty from performing its natural function the next time it is used.” (David Bradshaw - What Does it Mean to be Contrary to Nature?)
"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)
"Critics object that it needn’t be wrong to use organs for something other than their primary biological purpose; for example, there’s nothing wrong in using our feet to kick a football. So it needn’t be wrong to use sex organs for something other than their reproductive functions." (Harry J. Gensler - Ethics: A Contemporary Introduction, Chapter 13)
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 through 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. Even though chewing gum without any nutritional value is cheating my stomach, which is expecting real food; even though my chewing motion is going nowhere (and is proving to be futile) and thus unnecessarily straining my chewing muscles; even though something that cannot be chewed into small pieces and digested should be spat out immediately and should not be kept in the mouth; even though I might have the provocative attitude and intention of demonstratively perverting my food intake system while chewing, chewing gum is morally neutral in itself.
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.
“Presumably, the natural function of the ambulatory system is locomotion. Does not one who walks on a treadmill use this system in a way contrary to its natural function? Walking on a treadmill seems a rather precise parallel to having sex with a condom, for it involves performing the very act ofwalking while ensuring that its natural result, movement from one place to anothis does not occur. Or consider the respiratory faculty. Presumably, its natural function is to deliver oxygen to the bloodstream. People (or boys, at any rate) often enjoy inhaling helium because of the way it makes their voices absurdly high-pitched. Is this an unnatural use of the respiratory faculty? One might answer that it is not, because on the next breath they can always go back to inhaling normal air. But of course the same can be said of masturbation; it too uses a natural faculty for something other than its natural end without in any way preventing that faculty from performing its natural function the next time it is used.” (David Bradshaw - What Does it Mean to be Contrary to Nature?)
"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)
"Even if one could exhaustively describe the elements of our nature, the claim that we are morally obliged to act in accord with them, or to prefer “natural” uses to “unnatural,” could be made only as something additional and adventitious to the whole ensemble of facts that this description would comprise. Otherwise we could not see it as a moral good at all, but only as a negotiable feature of private taste. The assumption that the natural and moral orders are connected to one another in any but a purely pragmatic way must be of its nature antecedent to our experience of the world. I know of many stout defenders of natural law who are quick to dismiss Hume’s argument, but who — when pressed to explain themselves — can do no better than to resort to a purely conditional argument: ifone is (for instance) to live a fully human life, one must then . . . (etc.). But, in supplementing a dubious “is” with a negotiable “if,” one certainly cannot arrive at a morally categorical “ought.” (David Bentley Hart - Is, Ought, and Nature’s Laws. In: A Splendid Wickedness and Other Essays)
"The most gallant of Feser’s non sequiturs is his claim that, because reason necessarily seeks the good, there exists no gap into which any Humean distinction between facts and values can insinuate itself. But obviously the gap lies in the dynamic interval between (in the terms of Maximus the Confessor) the “natural” and “gnomic” wills. The venerable principle that the natural will is a pure ecstasy toward the good means that, at the level of gnomic deliberation, whatever we will we desire as the good, but not that philosophical theory can by itself prove which facts imply which values, or that the good must naturally be understood as an incumbent “ought” rather than a compelling “I want.” Feser asserts that “purely philosophical arguments” can establish “objective true moral conclusions.” And yet, curiously enough, they never, ever have. That is a bedtime story told to conjure away the night’s goblins, like the Leibnizian fable of the best possible world or the philosophe’s fairy tale about the plain dictates of reason." (David Bentley Hart - Nature Loves to Hide. In: A Splendid Wickedness and Other Essays)
"Feser claims that he does not have an “is-ought” problem. Maybe so, but he has merely replaced it with a “natures’s End - ought” problem that is equally tenacious. He still faces the question of “So nature intends that I X. But why should I X?” Seems to me he has gained nothing from that move." (Some internet commentator)
You can derive a practical 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)
"To get an absolute command (or ‘categorical imperative’, as we shall see later) you have to presuppose someone who gives that command. Within the natural law theory, as it has developed since the time of Aquinas, that ‘someone’ is God. This gives its moral pronouncements an authority that may not be justified by the logic on which the argument is based." (Thompson, Mel. Understand Ethics: Teach Yourself: Making Sense of the Morals of Everyday Living)
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)
There is also another normativity from which a pressure to act emanates, which presupposes one's own personal will. I'll give an example: I want to be home at ten o'clock in the evening, so I must (normative must or have to) take the bus at half past nine.
So, if you want y to happen, then you "must" do x, provided you really want to. There must be a strong interest in what is wanted or willed and not just a desire or wish.
However, this normative must would also be incompatible with natural law, since it depends on my personal will. Any normativity in the logical and practical sense tends to be in tension with the ethics of natural law.
"In Eastern philosophy, the idea of karma – that actions have consequences that cumulatively influence the future – relates the state of the world to moral choices. But this gives only a ‘hypothetical’ command (in other words, one that says ‘If you want to achieve X, then you must do Y’), not an absolute moral command." (Thompson, Mel. Understand Ethics: Teach Yourself: Making Sense of the Morals of Everyday Living)
If I already believe in the Catholic hell, it would work. I have to obey such and such rules of the Church because I don't want to go to the hell I already believe in from the beginning. If the belief in the Church (together with her specific idea that the nature of man is so and so and not otherwise) is absent, that normativity no longer exists.
Something else to consider:
"Elective priorities. Assume, however, that we can establish the existence of a moral imperative implicit in the orderliness of the world, as perceived by a rational will that, for itself, must seek the good: Does that assure that we can prove what hierarchy of values follows from this, or how we should calculate the relative preponderance of diverse moral ends? Yes, we may all agree that murder is worse than rudeness; but, beyond the most rudimentary level of ethical deliberation, pure logic proves insufficient as a guide to which ends truly command our primary obedience, and our arguments become ever more dependent upon prior evaluations and preferences that, as far as philosophy can discern, are culturally or psychologically contingent. Consistent natural law cases can be made for or against slavery, for example, or for or against capital punishment, depending on which values one has privileged at a level too elementary for philosophy to adjudicate. At some crucial point, natural law argument, pressed to disclose its principles, dissolves into sheer assertion." (David Bentley Hart - Is, Ought, and Nature’s Laws. In: A Splendid Wickedness and Other Essays)
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)
And why, according to the church, we supposedly have the bodily functions we do, has to do with their idea of the Eden period of Adam and Eve:
"It might help to read Aquinas and Augustine's take on progeneration in the Garden of Eden to understand why, historically, the sexual members have such specific functions.
The predominant view of the time was that either there would have been no procreation, or procreation would have occurred through some divine means. This because sexuality is bound up with lust, and lust is naughty. Aquinas and Augustine argue against the view by claiming that sex would have recurred without stirring the loins through lust." (A reddit view of a user named Quidfacis_)
"If the whole world is in a state of constant change; if galaxies are moving outwards towards an unknown future; if stars are born and die, and planets spinning around them are vulnerable to their death and many other cosmic accidents; if life on planet Earth is a recent phenomenon and subject to a process of evolution – how can the purpose or goal of anything be fixed?
The natural law approach is based on the idea that reason can interpret the essence, purpose and ‘final cause’ of things. We need to consider whether this is compatible with a world viewed from the perspective of evolution and change.
Is morality the result of deliberately going against our basic instincts, as suggested by Richard Dawkins at the end of The Selfish Gene: ‘We alone on earth can rebel against the tyranny of the selfish replicators’? Or is some sense of morality genetically programmed into us? Research on the behaviour of apes suggests that there may be the basics of morality – in the attitude of groups to individuals, and the support given by one individual ape to another. So, for example, animals that fight can ‘make up’ afterwards. Is this programmed into them in order to help the species survive in a competitive environment?" (Thompson, Mel. Understand Ethics: Teach Yourself: Making Sense of the Morals of Everyday Living)
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 possible and potential 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, the more right-wing leaning evolutionary psychology and the more left-wing leaning anthropology deal with this topic), 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.
"Even if final causality in nature is demonstrable, does it yield moral knowledge if there is no clear moral analogy between natural ends and the proper objects of human motive? For Thomas Aquinas, only a moral disorder can make one claim ignorance of the reality of the God who, as the source of one’s being, is supremely worthy of love. True in principle, of course. Even so, the “failure” to find a moral dimension in one’s intrinsic ontological contingency may not be entirely culpable. Our modern narrative of nature is of an order shaped by immense ages of monstrous violence: mass extinctions, the cruel profligacy of an algorithmic logic that squanders ten thousand lives to fashion a single durable type, an evolutionary process that advances not despite, but because of, disease, warfare, predation, famine, and so on. And the majestic order thus forged? One of elemental caprice, natural calamity, the mercilessness of chance — injustice thrives, disaster befalls the innocent, and children suffer. Why, our deracinated modern might ask, should we believe that nature’s organizing finality, given the kinds of efficient causes it prompts into action, has moral implications that command imitation, obedience, or (most unlikely of all) love?" (David Bentley Hart - Is, Ought, and Nature’s Laws. In: A Splendid Wickedness and Other Essays)
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)
And:
"[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)
"Our organs are not for anything, and they have no function or purpose: they do what they do, well or ill. Still less does the human body have a purpose or function; it is not for anything. That, of course, is one of the conclusions to be drawn from evolutionary theory.
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In any case, even if we could say unequivocally what the purpose of any given organ is, we cannot conclude that we ought to use it for that purpose, still less that we ought to use it only for that purpose. That just does not follow. If our hands had the purpose of manipulating objects, it would not follow from that that we ought to use them for that or that we ought not to use them for other things.
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If the sexual organs are for reproduction, it does not follow that they ought to be used for this purpose, not even if we grant that they may or even ought also to be used for other purposes. This no more follows than it follows from the fact (if it is a fact) that human teeth and digestive system are for the consumption of animal flesh (amongst other things) that we ought to eat meat. You cannot refute vegetarianism so easily." (Christopher Hamilton - Alexander Pruss on love and the meaningfulness of sex)
The Thomists, by the way, assume that teleology or final causality is the sufficient condition for their natural law ethics. The critic could merely deny that teleology exists in an objective sense, and the discussion would be over.
Even if one would admit teleology in nature, one could say that it is merely a necessary condition. It alone does not make natural law ethics possible, and the other necessary conditions can be questioned.
And even if one assumes that teleology is the sufficient condition and also recognizes its validity, then one could still argue eternally about what it now consists of exactly and in detail with the human being.
It is important to mention that for the Thomists, natural things and processes have only one purpose or one that is primary. However, this is pure dogma.
It goes back to Aristotle, who is generally not free of dogmas. His thesis that the species of living things are eternally constant in a certain sense is a dogma that has long dominated the thinking of biologists. It is precisely this dogma that entails the other, which is relevant in natural law ethics. The evolutionary approach, on the other hand, assumes the great importance of the habitat context for the living beings and their abilities.
Moreover, the dogma seems to violate an Aristotelian principle: Namely, it is Aristotle's thesis that the foundational structure in the products of human manufacture is quite the same as in natural things. Art imitates nature is his famous formula for this. It is familiar to us today mainly in limited application: as an antiquated maxim of the fine arts. For Aristotle, however, the scope of the sentence extends to all kinds of human achievements, i.e., to 'art' in the broadest sense.
The natural faculties of man may well be analogous to a hammer:
"A hammer my have been designed to pound nails, and it may perform that particular job beg. But it is not sinful to employ a hammer to crack nuts ff I have no other more suitable toot immediately available. The hammer, being a relatively versatile tool, may be employed in a number of ways. It has no one "proper" or "natural" function." (http://faculty.cbu.ca/sstewart/sexlove/leiser.htm)
After all, according to Ackrill, Aristotles admits that an organ can have two essential purposes, as in the case of the elephant trunk:
"In the following discussion of the elephant's trunk notice the reference to the animal's environment: since he lives in swamps he has to have such-and-such if he is to be able to breath and feed. This is very close to the evolutionist's way of speaking: unless he had means of breathing and feeding in swamps he would not have survived in swamps. Notice also in this example the idea that a part essential for one purpose may also serve a second purpose." (J. L. Ackrill – Aristotle the Philosopher)
Ackrill then gives another example of Aristotle, of which he says:
"Here is another case of one organ with two jobs, but here one job is of a higher order than the other[.]" (J. L. Ackrill – Aristotle the Philosopher)
It is clear that Ackrill understands Aristotle to mean that a natural thing can actually have two different primary, essential functions depending on the context or environment. Thus, Aristotle would contradict his own established dogma.
It should not be controversial that an organ can be given with two tasks of equally high order. If this can be true for organs, why not also for all natural faculties?
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)
"Feser’s argument about sexual ethics makes the mistake of beginning with the ends of one bodily system (the reproductive system) and presuming them to be ends of the person as a whole." (Melissa Moschella - Old Natural Law Theory, Marriage, and Sexual 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)
And:
"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)
And:
"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)
"One might argue that the presence of sexual organs in a human being implies that he or she is designed for sexual activity and the conception of children – in which case, celibacy is as unnatural as homosexuality, since it is a denial of the complete natural function of procreation. If this is established, then it is illogical to accept a celibate partnership between those who are sexually attracted.
Some people are naturally attracted by members of the same sex. They experience their feelings as completely natural. Any difficulties that arise are the result of social conditioning, not nature.
Sexuality can be said to achieve three ends: 1. physical pleasure 2. the deepening of a relationship 3. the conception of children Only the third end is precluded by homosexual relationships. But is not the search for pleasure and for deep relationships as natural as the conception of children? If a marriage is known to be infertile, are heterosexual acts between its partners therefore immoral simply because conception is impossible
Marriage is a social function, and promiscuity can be practised equally by homosexuals and heterosexuals. The fact that homosexual couples cannot marry does not preclude deep and permanent relationships.
If a homosexual couple form a stable relationship, they may be able to offer children a home that is, at the very least, as valuable to their upbringing as one in which there is either a single parent, or a heterosexual couple with a bad relationship. Hence, it would seem illogical to discriminate in this matter.
In pointing out some of the ways in which the ‘natural law’ view of the homosexual couple’s situation might be challenged, it is not intended to undermine the principle of natural law as such, but to show that there are some areas of morality – particularly where relationships are concerned – where it is difficult to consider morality mainly in terms of specific actions." (Thompson, Mel. Understand Ethics: Teach Yourself: Making Sense of the Morals of Everyday Living)
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)
"Sex within the ‘safe period’ of the woman’s ovulatory cycle is generally permitted in Catholic moral teaching because the failure to conceive at that time is part of nature’s limitation, rather than the result of a direct attempt to do something unnatural." (Thompson, Mel. Understand Ethics: Teach Yourself: Making Sense of the Morals of Everyday Living)
Is the mentioned "nature's limitation" a defect, or does it correspond to a natural design? The latter seems more likely, and therefore the following applies:
"At the most on four days a month is the union of intercourse and fertility normal. If we seek to understand the divine plan from what nature has given humanity, we must infer that it is for a brief part of any life that fertility is intended, and that nature has designed man so that many acts of intercourse will be sterile. […] The reason a sterilizing act is wrong is that it asserts man's dominion over the generative process and effects the disruption of the natural nexus. But when steps are taken to assure that intercourse is not fertile in a period not intended by nature to be fertile, man acts in subordination to the divine plan and does not effect any disruption of the sacred link between love and fertility. Further, the directly intended act is the assurance of natural sterility. [...] But at those times when nature intends no procreation, there is no interference in the structure or signification of the sexual act when means are used increasing the probability that the natural rhythm will hold." (John T. Noonan, Jr. - Contraception A History of Its Treatment by the Catholic Theologians and Canonists)
And:
“Perhaps most interestingly, a physician who played a leading role in the development of the Pill, John Rock, argued vigorously that the Pill fit comfortably within existing Catholic teaching. He reasoned that since it uses a naturally occurring hormone, progesterone, to extend a woman's infertile period, it is effectively no more than an aid to the rhythm method.” (David Bradshaw – What Does it Mean to be Contrary to Nature?)
Is the mentioned "nature's limitation" a defect, or does it correspond to a natural design? The latter seems more likely, and therefore the following applies:
"At the most on four days a month is the union of intercourse and fertility normal. If we seek to understand the divine plan from what nature has given humanity, we must infer that it is for a brief part of any life that fertility is intended, and that nature has designed man so that many acts of intercourse will be sterile. […] The reason a sterilizing act is wrong is that it asserts man's dominion over the generative process and effects the disruption of the natural nexus. But when steps are taken to assure that intercourse is not fertile in a period not intended by nature to be fertile, man acts in subordination to the divine plan and does not effect any disruption of the sacred link between love and fertility. Further, the directly intended act is the assurance of natural sterility. [...] But at those times when nature intends no procreation, there is no interference in the structure or signification of the sexual act when means are used increasing the probability that the natural rhythm will hold." (John T. Noonan, Jr. - Contraception A History of Its Treatment by the Catholic Theologians and Canonists)
And:
“Perhaps most interestingly, a physician who played a leading role in the development of the Pill, John Rock, argued vigorously that the Pill fit comfortably within existing Catholic teaching. He reasoned that since it uses a naturally occurring hormone, progesterone, to extend a woman's infertile period, it is effectively no more than an aid to the rhythm method.” (David Bradshaw – What Does it Mean to be Contrary to Nature?)
