Reading Time: 6 minutes Ed Feser, via YouTube
Reading Time: 6 minutes

Yesterday, I posted on the subject of Natural Law Theory (NLT) in the context of the enjoyment of sex. NLT states that behaviours that are rationally chosen by an agent that do not fit the remit of the final cause of the agent or part of the agent (i.e., a body part) are morally bad. In the same way a kettle that doesn’t work well to boil water is a bad kettle, if the supposed final cause or purpose of a penis is to urinate and procreate, then any behaviour that falls outside of the remit of excretion or reproduction (procreation) is morally bad.

The term that Edward Feser, natural law theorist, uses is “frustrate” such that if the activity frustrates the final cause, then it is morally bad. In the case of sex, where the final cause is reproduction, wearing a condom “frustrates” reproduction. Having sex exclusively for enjoyment (i.e., wearing a condom) is therefore morally wrong. This is different to saying enjoying sex is morally wrong, since it is actually at least neutral if having sex for the primary purpose of reproducing.

In the book I am editing (The Unnecessary Science), the author (who blogs as Gunlord500 here) states:

One problem with Feser’s argument here, which other critics have noted, is that Natural Law would seem to condemn heterosexual sex between infertile people, even within marriage, or even in a fertile couple when the woman is pregnant! Feser addresses this as well, saying “[f]oreseeing that a certain sexual act will in fact not result in conception is not the same thing as actively altering the relevant organs [i.e., attaching a condom or diaphragm to one of them] or the nature of the act [same-sex intercourse, masturbation, bestiality, etc.] in a way that would make it impossible for them to lead to conception even if they were in good working order.”[1] That would seem to wrap things up nicely for the Natural Law theorist, but the perceptive reader can see it raises even more problems in the attempt of solving one.

Is “actively altering” the sex act always inherently wrong? There seem to be several scenarios when most people would say it is morally licit. Imagine a loving heterosexual married couple where one partner, through no fault of his or her own, has contracted a venereal disease. Perhaps, through great misfortune and shockingly lax procedure, one of them received a tainted blood transfusion, or an untrained nurse at a hospital took a blood sample with a re-used needle rather than a new, sterile one. Afterwards, the afflicted partner insists they use condoms whenever they have relations, in order to keep the disease from infecting the other. This would obviously also prevent conceiving any children, but since the disease would then pass on to the couple’s offspring, public health demands their nest remains empty. Under the circumstances, then, it would be a hard sell to condemn the couple for using at least one form of contraception, if no others.

Feser might argue that the pair would be morally obligated to remain celibate until the infected partner has been cured, or indefinitely if the disease is non-curable. But this would strike most as both draconian and impractical. If such a couple would be denied the joys of parenthood due to an unfortunate incident they could not foresee nor be blamed for, it seems manifestly unjust to compound their misfortunes by forbidding them to have sex, especially when a simple technological solution would allow them that small pleasure. More likely Feser would allow them an exception based on their intent. They may be “actively altering their relevant organs” with a condom, but since their intent was to protect the healthy partner rather than “frustrate the function” of the act per se, the endeavor wouldn’t be morally wrong.

Unhappily for Feser, this would seem to lessen, if not entirely negate, the moral wrongness of other kinds of non-procreative sex. When a man masturbates, he is not necessarily consciously intending to “frustrate” the end of his sexual faculties. He might be overcome with lust, desperately lonely, or just looking for a little fun, but those sorts of direct intentions would seem to be morally neutral rather than good or bad, using Feser’s definitions of good and bad as facilitating or frustrating a bodily function. The same applies to homosexual behavior. Two men having sex might be lustful, looking for fun, or looking to bond, but not necessarily consciously intending to “frustrate” the function of their faculties, even if they would be able to “foresee their behavior would not lead to conception.” If it is licit for a couple to “actively alter the sex act/relevant organs” if their intentions are praiseworthy, it ought to be licit for a couple to do the same if their intentions are merely neutral. The only time non-procreative sex would be truly “bad” in Feser’s sense would be if it were undertaken for the explicit purpose of contraception—a man using a condom or having same-sex intercourse for no other purpose than to prove he could, or a man masturbating even when given the opportunity for sex with a willing and eager partner. Those are apparently the only situations which fulfill Feser’s criteria for moral wrongness, “[using one’s sexual faculties] for the sake of actively frustrating the realization of [their ends].”[2] Given the rarity of such situations, a blanket condemnation of non-procreative sex in general seems unsustainable.

Or does it? Feser believes that “[a]n act can in fact actively frustrate the end whether or not one has such frustration consciously in view, just as an act can in fact be free of such active frustration whether or not avoiding such frustration is consciously in view.”[3] But even with this consideration, Feser’s argument remains unconvincing. First off, it would seem to disregard the importance of intent in moral action. It is fairly uncontroversial that an act can be morally better or worse due to its intention. If you run a man over with your car because you hate him, you’ve obviously committed an evil act, but if you run him over accidentally, you’re less culpable, and if you run him over because he himself is doing evil (carrying out a mass shooting, say), you have actually done good. If we can agree on that, we can agree that gays and lonely straights are not committing quite as much evil as Feser might have it, so long as their intents are mere pleasure rather than spitefully frustrating final causality for the sake of it.

[1] Ibid, 400.

[2]NSE, 399.

[3] Edward Feser, “Foundations of Sexual Morality,” Edward Feser, February 7, 2017, comment at February 10, 2017, 9:40 AM, last accessed March 25, 2018,

I think the last paragraph (and indeed, the author continues on from here) demands some discussion because I wonder whether having sex for enjoyment only (wearing a condom) only frustrates the final cause in the short term. In this way, there is no intention from either agent to frustrate the ability to reproduce in either agent, such as intentionally dismembering oneself would.

Take, for example, the aforementioned kettle. Someone breaks into my house and shoots me with a gun. I pick up the kettle and use it to block the bullet, which ricochets off the kettle, damaging the button. The kettle was used in a way that now renders it a bad kettle. The kettle was used in a way that actively frustrated its final cause (you could add a layer of complexity by saying I knew, in the split second, what would happen and decided to save my life by intentionally damaging the kettle). However, in the long run, I fix the button easily and can use the kettle again to intentionally and soundly bring about its final cause.

Here, you could say that saving my life trumped the (for the sake of argument) moral negativity of using the item in frustrating its final cause.

The difference with the sex scenario is that sex brings about life and therefore (NLT proponents would say) has a high moral value, and frustrating it for the sake of enjoyment, I imagine, is not a morally good trumping.

But to use a condom is only to frustrate the final cause in that single instantiation of sex, not with any permanence. Should this be taken into account?

At the end of the day, God does this every time, as an OmniGod, he allows (indeed, designed into the system) fertilised embryos to fail to implant or naturally abort, to the tune of billions of human “lives” over time already. This frustration of the final cause must be trumped by a greater good every single time, though one wonders what this might be. It also shows how, in that context, NLT is itself trumped by some kind of consequentialism.

Of course, I fundamentally see NLT failing on a whole bunch of other criteria outside of this (it doesn’t even get past the barriers that conceptual nominalism poses, and ideas of subjectivity (see the RELATED POSTS below).




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A TIPPLING PHILOSOPHER Jonathan MS Pearce is a philosopher, author, columnist, and public speaker with an interest in writing about almost anything, from skepticism to science, politics, and morality,...

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