Like so many of the ideas and arguments we’ve looked at already, natural law theory is very badly misunderstood by those who criticize it. The usual objections go like this: “If it’s wrong to go against nature, then isn’t it wrong to wear glasses, ride bicycles, etc., since these aren’t natural but artificial?” “If what’s good is what’s natural, isn’t everything we do therefore good, since everything that happens in nature is by definition ‘natural’?” “If homosexuality is genetic, doesn’t that show that it’s natural too?” And so on, tiresomely and cluelessly.
Perhaps it is obvious from what’s been said already what is wrong with these objections, but if not, here it is. The “nature” of a thing, from an Aristotelian point of view, is, as we’ve seen, the form or essence it instantiates. Hence, once again to haul in my triangle example, it is of the essence, nature, or form of a triangle to have three perfectly straight sides.7 Notice that this remains true even if some particular triangle does not have three perfectly straight sides, and indeed even though (as I’ve repeated ad nauseam) every material instance of a triangle has some defect or other. The point is that these are defects, failures to conform to the nature or essence of triangularity; the fact that such defective triangles exist in the natural world and in accordance with the laws of physics doesn’t make them any less “unnatural” in the relevant sense.
When we get to biological organs, we have things whose natures or essences more obviously involve certain final causes or purposes. So, for example, the function or final cause of eyeballs is to enable us to see. But suppose someone’s eyeballs are defective in some way, making his vision blurry. In that case, to wear eyeglasses isn’t contrary to the natural function of eyeballs; rather, it quite obviously restores to the eyeballs their ability to carry out their natural function. Bicycles don’t do this, of course, but they do extend, rather than conflict with, the ability of the legs to carry out their natural function of allowing us to move about.
Finally, to round out this initial reply to some standard bad objections to natural law theory, while it is true that some defenders and critics of traditional sexual morality seem to worry themselves endlessly about whether homosexuality has a genetic basis, the question is actually largely irrelevant, and they shouldn’t waste their time. For it is quite obvious that the existence of a genetic basis for some trait does not by itself prove anything about whether it is “natural” in the relevant sense. To take just one of many possible examples, that there is a genetic basis for clubfoot doesn’t show that having clubfeet is “natural.” Quite obviously it is unnatural, certainly in the Aristotelian sense of failure perfectly to conform to the essence or nature of a thing. And no one who has a clubfoot would take offense at someone’s noting this obvious matter of fact, or
find it convincing that the existence of a genetic basis for his affliction shows that it is something he should “embrace” and “celebrate.” Nor would it be plausible to suggest that God “made him that way,” any more than God “makes” people to be born blind, deaf, armless, legless, prone to alcoholism, or autistic. God obviously allows these things, for whatever reason; but it doesn’t follow that He positively wills them, and it certainly doesn’t follow that they are “natural.” So, by the same token, the possibility of a genetic basis for homosexual desire doesn’t by itself show that such desire is natural. Homosexual activists often breathlessly cite this or that alleged “finding” that such a basis exists; someday they might even cite something plausible. “Whatever, dude,” as the kids say. Even if it is established beyond a reasonable doubt that there is such a basis, with respect to the question of the “naturalness” of homosexuality, this would prove exactly zip.
Of course, that by itself does not show that homosexuality is immoral either. After all, having a clubfoot is not immoral, and neither is being born blind or with a predisposition for alcoholism. These are simply afflictions for which the sufferer is not at fault, and can only call forth our sympathy. On the other hand, if someone born with normal feet wanted to give himself a clubfoot through surgery, we would find this at the very least irrational; and if someone concluded from his having a genetic predisposition for alcoholism that regularly drinking to excess would be a worthwhile “lifestyle” for him to pursue, then we would regard him as sorely mistaken, even if he could do this in a way that allowed him to hold down a job, keep his friends and family, and avoid car accidents. Even amid the depravity of modern civilization, most people realize that the life of an alcoholic is simply not a good thing, even if the alcoholic himself thinks it is and even if he “doesn’t hurt anybody else.” We know in our bones that there is something ignoble and unfitting about it. In the same way, should it turn out that a desire to molest children has a genetic basis, no one would conclude from this that sexual attraction toward children is a good thing, even if the person who has it was able to satisfy his disgusting urges without actually touching any children. We all know in our bones that someone obsessed with masturbating to pictures of naked toddlers is sick, and not living the way a human being ought to live, even if he never leaves the darkness of his own room and his own soul.
Now I realize, of course, that many readers will acknowledge that we do in fact have these reactions, but would nevertheless write them off as mere reactions. “Our tendency to find something personally disgusting,” they will sniff, “doesn’t show that there is anything objectively wrong with it.” This is the sort of stupidity-masquerading-as-insight that absolutely pervades modern intellectual life, and it has the same source as so many other contemporary intellectual pathologies: the abandonment of the classical realism of the great Greek and Scholastic philosophers, and especially of Aristotle’s doctrine of the four causes. For we need to ask why there is a universal, or near universal, reaction of disgust to certain behaviors, and why certain traits count as unnatural even if there is a genetic factor underlying them. And when the “evolutionary psychologists,” “rational choice theorists,” and other such Bright Young Things and trendies have had their say, there can still be no satisfying answer to these questions that does not make reference to Aristotelian final causes – even if only because there can be no satisfying explanation of almost anything that doesn’t make reference to final causes.
Let’s back up then, and see what morality in general looks like from a point of view informed by Aristotelian metaphysics, and then return later on to the question of sexual morality in particular. Like Plato, Aristotle takes a thing’s form, essence, or nature to determine the good for it.
Hence, a good triangle is one that corresponds as closely as possible to the form of triangularity, its sides drawn as perfectly straight as possible, etc. A good squirrel is one that has the typical marks of the species and successfully fulfills the characteristic activities of a squirrel’s life, e.g. by not having broken limbs, not gathering stones for its food rather than acorns, etc. So far this is obviously a non-moral sense of “good” – the claim isn’t that triangles and squirrels are deserving of moral praise or blame – and corresponds closely to the sense in which we might think of something as a “good specimen” or “good example” of some kind or class of things. But it is the foundation for the distinctively moral sense of goodness.
Even from the squirrel example it is obvious that for any animal there are going to be various behaviors that are conducive to its well being and others that are not, and that these latter will be bad for it whatever the reason it wants to do them. So, to return to an obvious example from Chapter 2, if a squirrel has some genetic mutation that makes it want to lay itself out spread-eagled on the freeway, the fact that it enjoys doing this obviously does not entail that it is good for it to do so. Or, to take another but less obvious example from Chapter 2, if you somehow conditioned a squirrel to live in a cage and eat nothing but toothpaste on Ritz crackers, to such an extent that it no longer wanted to leave the cage, scamper up trees, and search for acorns, etc., even when given the chance, it wouldn’t follow that the life of a Colgate addict is a good life for this particular squirrel. The sickly thing is simply not as healthy and “happy” a squirrel as he would have been had he never got himself into this fix, even if he has (of course) no way of knowing this. And again, this would remain true even if the squirrel had a genetic predisposition to like the taste of Colgate and dislike the taste of acorns, one that was not present in other squirrels. That predisposition simply wouldn’t “jibe” with the overall structure of the natural physical and behavioral characteristics that are his by virtue of his instantiating the nature of a squirrel, however imperfectly. The predisposition would be a defect, like a puzzle piece that won’t fit the rest of the puzzle.
Now, when we turn to human beings we find that they too have a nature or essence, and the good for them, like the good for anything else, is defined in terms of this nature or essence. Unlike other animals, though, human beings have intellect and will, and this is where moral goodness enters the picture. Human beings can know what is good for them, and choose whether to pursue that good. And that is precisely the natural end or purpose of the faculties of intellect and will – for like our other faculties, they too have a final cause, namely to allow us to understand the truth about things, including what is good for us given our nature or essence, and to act in light of it. Just as a “good squirrel” is one that successfully carries out the characteristic activities of a squirrel’s life by gathering acorns, scampering up trees, etc., so too a good human being is one who successfully carries out the characteristic activities of human life, as determined by the final causes or natural ends of the various faculties that are ours by virtue of our nature or essence. Hence, for example, given that we have intellect as part of our nature, and that the purpose or final cause of the intellect is to allow us to understand the truth about things, it follows that it is good for us – it fulfills our nature – to pursue truth and to avoid error. So, a good human being will be, among many other things, someone who pursues truth and avoids error. And this becomes moral goodness insofar as we can choose whether or not to fulfill our natures in this way. To choose in line with the final causes or purposes that are ours by nature is morally good; to choose against them is morally bad.
"But why should we choose to do what is good for us in this Aristotelian sense?” someone might ask. The answer is implicit in what has been said already. The will of its very nature is oriented to pursuing what the intellect regards as good. You don’t even need to believe in Aristotelian final causes to see this; you know it from your own experience insofar as you only ever do something because you think it is in some way good. Of course you might also believe that what you are doing is morally evil – as a murderer or thief might – but that doesn’t conflict with what I’m saying. Even the murderer or thief who knows that murder and stealing are wrong nevertheless thinks that what he’s doing will result in something he regards as good, e.g. the death of a person he hates or some money to pay for his drugs. I mean “good” here only in this thin sense, of being in some way desirable or providing some benefit. And that is all Aquinas means by it when he famously tells us that the first principle of the natural law is that “good is to be done and pursued, and evil is to be avoided.” This is not meant by itself to be terribly informative; it is meant only to call attention to the obvious fact that human action is of its nature directed toward what is perceived to be good in some way, whether it really is good or not.
But when we add to this the consideration that the good for us is in fact whatever tends to fulfill our nature or essence in the sense of realizing the natural ends or purposes of our various natural capacities, then there can be no doubt as to why someone ought to do what is good in this sense. For you do by nature want to do what you take to be good for you; reason reveals that what is in fact good for you is acting in a way that is conducive to the fulfillment of the ends or purposes inherent in human nature; and so if you are rational, and thus open to seeing what is in fact good for you, you will take the fulfillment of those ends or purposes to be good for you and act accordingly. This may require a fight against one’s desires and such a fight might in some cases be so extremely difficult and unpleasant that one might not have the stomach for it. But that is a problem of will, not of reason. It doesn’t show that the rational thing is not to struggle against one’s desires, but only that doing the rational thing can sometimes be extremely difficult and unpleasant. An obvious illustration of this is what happens when someone decides to stop drinking to excess: He previously thought drinking to excess was a good thing to do, or at least not a habit worth struggling against; then he realizes that it is not a good thing to do, and in fact that it would be good to stop doing it; and so he decides to stop doing it. Now he may well find that implementing this decision is extremely difficult; he may even come to find it so difficult that he starts to think it impossible. But that doesn’t mean that to stop drinking to excess really isn’t what is good for him, and thus what reason recommends. It only shows that his will has become so extremely corrupted that he is unable, or nearly unable, to do what it is good and rational for him to do. And notice this remains true whether or not his excessive drinking was in some way facilitated by some genetic factor. The presence of such a factor would not show that excessive drinking is good for him after all, but only that because of some tragic defect outside his control, he finds it more difficult than other people do to do what is good and rational. This would certainly reduce his culpability, and justify us in treating him with greater compassion and understanding than we might treat someone without such a handicap, but it would not justify revising our judgment that what he is doing is objectively bad and irrational.
. It would be very funny if he actually ended up doing better than Nick.
