You’ve got your natural law. You’ve got your natural rights. You’ve got the state of nature. Then there’s naturalism. And laws of nature. And the supernatural. There’s St. Paul’s natural man and the Scholastics’ natura pura. There’s nature and nature’s God. There’s natural science, natural history, natural selection, natural theology, natural philosophy, and the philosophy of nature. There’s the Baconian scientist putting nature on the rack, and Galileo telling us that the book of nature is written in the language of mathematics. And let’s not forget the literal books, like Lucretius’s On the Nature of Things, Hume’s Treatise of Human Nature, Richard Rorty’s Philosophy and the Mirror of Nature, and Edward O. Wilson’s On Human Nature. There’s Emerson’s essay “Nature.” For fans of underground comics, there’s Mr. Natural;for fans of obscure superheroes too preposterous ever to get their own billion-dollar-grossing film adaptations, there’s Nature Boy. There’s Oliver Stone’s movie Natural Born Killers and Robert Redford in The Natural. There’s Ringo Starr singing “Act Naturally,” Aretha Franklin’s “(You Make Me Feel Like) A Natural Woman,” the Steely Dan album Two Against Nature, and that stupid Gilbert O’Sullivan tune.
There are natural disasters, natural resources, natural gas, and dying of natural causes. There’s natural beauty, but also freaks of nature. There’s going back to nature and getting a natural high. There are Mother Nature, nature hikes, all natural foods, natural family planning and natural childbirth. There’s the natural order, and second nature. There are natural numbers. There are all the examples I didn’t think of. There are blog posts that are starting to sound like George Carlin routines.
With “nature” and “natural” used in so many different ways, it’s no wonder people often misunderstand what classical natural law theorists mean when they define the good for man in terms of what is natural and what is bad as what is contrary to nature. Hence the blizzard of clueless objections: “If what is unnatural is wrong, then wouldn’t eyeglasses and prosthetic limbs be wrong?”; “But everythingis natural, since everything follows the laws of nature”; “If I was born this way, then it must be natural”; etc. Remarks of this sort reflect fundamental misconceptions about what the natural law theorist means by “nature.” (Again, I’m talking about classical natural law theory there, the kind rooted in classical metaphysics of the broadly Platonic, Aristotelian, and/or Scholastic kind. I’ll let “new natural law theory” adepts speak for themselves.)
The basic idea is really not all that complicated, and can be understood at least to a first approximation by reference to everyday examples. Everyone knows that it is in the nature of grass to require water and sunlight but not too much heat, and that for that reason it is good for grass to be watered and well lit and bad for it to lack water and sunlight or to be exposed to great heat. Everyone knows that is in the nature of a tree to require soil into which it can sink its roots and from which it can draw water and nutrients, and thus that it is good for a tree so to sink them and bad for it if it is somehow prevented from doing so. Everyone knows that it is in the nature of a squirrel to gather nuts and the like and to dart about in a way that will make it difficult for predators to catch it, and thus goodfor it to do these things and bad for it if for whatever reason it fails to do them. The natures of these things entail certain ends the realization of which constitutes their flourishing as the kinds of things they are.
Hence, no one would make stupid remarks to the effect that to say that some things are naturally good for squirrels would entail, absurdly, that putting a little splint on a squirrel’s broken leg to help it heal would be “unnatural”; or that to say that some things are naturally good for grass would entail, absurdly, that watering it with sprinklers rather than rainwater would be “unnatural.” For it is quite obvious that, though man-made and thus artificial, neither of these things is unnatural in the relevant sense. A splint doesn’t frustrate the realization of the ends a squirrel has to fulfill in order to flourish as the kind of thing it is, and sprinklers don’t frustrate the ends grass must realize in order to flourish as the kind of thing it is. On the contrary, the splint and the sprinklers facilitate the realization of those ends.
Similarly, no one would object that it is trivial to talk about what is natural for a tree, a squirrel, etc., since, after all, everythingfollows the laws of nature anyway. For though it is of course true that all material things are subject to the laws of physics, different kinds of material things have their own distinctive natures that determine distinctive kinds of flourishing. Darting about is something a squirrel needs to be able to do in order to flourish as the kind of thing it is, but it is not the sort of thing a tree or grass needs to do in order to flourish as the kinds of thing they are. In addition to the laws that govern all material things as such, there are less fundamental laws that govern only specific parts of nature, and it is these that reflect the goods distinctive of these various parts.
Nor would anyone would raise silly objections to the effect that if a certain squirrel is born without a leg, then it must be natural for that squirrel to lack four legs, or that if a certain sickly tree fails to sink roots into the ground and ends up falling over or drying out, then it must be natural for that tree to fail to sink roots. For though these circumstances are “natural” in the sense that they sometimes occur in the ordinary course of nature and arise from factors internal to the things in question rather than from human action or some other external factor, they are nevertheless unnatural in the relevant sense. For a squirrel’s being born without a leg or a tree’s having weak roots constitute failures to realize the ends that define the flourishing of these sorts of thing, and thus are failures fully to realize a thing’s nature. That is why we call them defects in a thing.
Now, none of these examples involves moral goodness or badness, because morality involves intellect and will, which grass, trees, and squirrels all lack. Rational creatures like ourselves are capable of moral goodness or badness precisely because we do have intellects and wills. The will itself has as its natural end the pursuit of the good, and determining what is in fact good is part of the natural end of the intellect. Morally good action thus involves the will to do what is good for us given our nature, while morally bad action involves willing contrary to what is good for us given our nature. And to the extent that the intellect knows what is good for us we are culpable for these good or bad actions. To will to do what is “natural” for us thus means, in classical natural law theory, something like to will to do what tends toward the realization of the ends which, given our nature, define what it is for us to flourish as the kind of things we are. And to will to do what is “unnatural” thus means something like willing to do what tends toward the frustration of the ends which, given our nature, define what it is for us to flourish as the kind of things we are.
If a squirrel were rational, it would be natural and good for him to will to escape predators and to gather nuts for the winter and unnatural and bad for him to will to offer himself up to predators and to eat only toothpaste or stones. And the latter would be unnatural and bad for him whatever was the reason why he willed these things -- brain damage, genetic anomalies giving rise to odd desires, bad squirrel upbringing, squirrel peer pressure, the influence of squirrel pop culture, arguments from squirrel philosophers who were hostile to natural law, or whatever. They would also be unnatural and bad for him however strongly he wanted to eat the toothpaste and offer himself to the predators, and even if he found the idea of eating nuts and fleeing from predators repulsive. The provenance and strength of the desires wouldn’t show that they were somehow natural (again, in the relevant sense) but on the contrary indicate instead how deeply distorted and unnatural the squirrel’s character had become -- like a hose that’s gotten so many kinks in it that it is hard to get water through it anymore, or a vine whose growth pattern has gotten so twisted that it ends up choking itself to death.
Now where human beings are concerned, to know in detailwhat our nature determines to be good for us would require a careful analysis of each of our various faculties and capacities -- reason, speech, labor, sex, and so forth. I’m not going to get into all of that here because it is not relevant to the point of the post, and each of these would in any event require a treatment of its own. (I’ve addressed some of these issues in other places, such as in The Last Superstition, in my Social Philosophy and Policy article “Classical Natural Law Theory, Property Rights, and Taxation,” and in blog posts like this one and this one.) No natural law theorist claims that merely saying “Act in accordance with nature” is the end of the story. It’s just the beginning of the story. The point for now is that while the details about what counts as acting in accordance with nature or contrary to nature in particular cases raise all sorts of questions, the general ideaof acting in accordance with nature is not subject to glib objections of the sort referred to above.
Thus, when natural law theorists talk about acting in accordance with nature, they do not mean “natural as opposed to artificial or man-made.” For example, when they say that contraception is bad, they don’t mean that it’s bad because it involves the use of pills, or mechanical devices, or man-made substances like rubber. They mean that it positively frustrates the natural ends of the sexual faculties (or at least partially frustrates them, since it is not denied that sex is naturally oriented toward bonding the spouses, expressing affection, and the like, as well as toward procreation). And methods that do not involve the use of any man-made or artificial devices (such as withdrawal) can frustrate this end just as much as the others can, and therefore are in the relevant sense “unnatural.” (Again, I’m not trying here to answer every question one might raise about this specific example, just indicating the sense of “natural” that is operative.)
Artificial or man-made devices as such are not only not “unnatural” in the relevant sense, they can restore or even facilitate the natural end of our capacities, as eyeglasses, tools, computers, prosthetic limbs, etc. do. (And this is as true in the sexual context as in other contexts -- an impotent man who used Viagra would be facilitating the natural end of his sexual faculties rather than frustrating them.) Nor is there anything in natural law theory that entails even a preference for what is “natural” as opposed to artificial (Luddism, living in the woods à la Thoreau, a fetish for “organic foods,” etc.). On the contrary, given that we are distinctively rational animals, technology and other products of artifice are manifestations of our nature.
In commending what is in accordance with our nature, natural law theorists also do not mean “natural in the sense of commonly occurring in the ordinary course of nature.” All sorts of things commonly occur in the ordinary course of things that tend to frustrate our nature -- injuries, diseases, floods, earthquakes, and, for that matter, immoral choices. Hence when people say that it is “natural” for a child to be selfish or for a man to have a roving eye, while there is a sense in which this is true, it is not the sense that is operative in natural law theory. A goldfish will “naturally” tend to keep eating the food you drop into its tank even after it is full, but that hardly fulfills its nature in the relevant sense (since it will overeat and thereby kill itself). Similarly, we have, given our limited nature as created things, inherent susceptibilities to defects and failures of various kinds -- overeating, overreaction to injustices, excessive fear in the face of danger, sexual vices, bodily injury, the contraction of various diseases, etc. These are not “natural” in the relevant sense of fulfilling our nature even though they are “natural” in the different sense that they are defects or failures to which we are prone to given our nature.
For the same reason, the natural law theorist does not mean “natural in the sense of flowing from a deep-seated tendency.” For a deep-seated tendency could result from habituated vice or heredity defect, either of which would be contrary to nature in the relevant sense. A predisposition to alcoholism or heart disease doesn’t help the person who has it to realize the ends inherent in his nature, even if such a predisposition has a genetic basis. A character trait may have become so habituated that it has become “second nature,” but that doesn’t make it natural in the relevant sense either.
The natural must also be carefully distinguished from the supernatural, where in classical natural law theory the “supernatural” has nothing to do with ghosts and other paranormal phenomena, but rather with what is above or additional to our nature and the ends inherent in it. For example, knowledge of God is something of which we are capable given our nature and which we require for our complete flourishing as the kinds of things we are -- that is why natural theology is possible -- but the intimate, “face to face” knowledge of God that is the beatific vision is not “natural” in that sense. That is rather a matter of grace, of being raised to an end higher than what we would be due or capable of given our nature. (I have said more about this hereand here.)
The tendency to confuse the natural and the supernatural can be found not only in the opponents of natural law theory but also in some of its friends. On the one hand there are critics of Catholic sexual morality who suppose that it is grounded merely in scripture, or tradition, or the authority of the popes. And on the other hand there are well-meaning orthodox Catholic writers who at least seem to suppose that Catholic sexual morality can only be understood and defended in theological terms -- in terms of the “theology of the body,” say, or “covenant theology.” Both suppositions are in error, for at least the fundamental aspects of Catholic sexual morality (and certainly its most controversial aspects) are grounded in natural law, and thus in premises that are accessible to all human beings (whether or not they are Catholic) and that would remain true even if there had been no divine revelation on which to base the theological approaches in question.
That is not to say that these theological approaches to do not have value. The point is rather that they are not and cannot be complete accounts of sexual morality. They can supplement what we know from natural reason, but cannot replace it. For gracebuilds on nature. When we ignore nature in favor of grace or blur the boundary between them, we distort the latter and make the former inaccessible to those who do not know or accept divine revelation. That is why, for many non-Catholics, Catholic teaching on sexual morality falsely seems like mere diktat, or at best something purely theological that can have appeal only to those already convinced of the moral relevance of the story of Adam and Eve, or of analogies between spouses on the one hand and Christ and the Church on the other.
This brings us to the “law” side of natural law, and thus to another term used in various senses which need to be carefully distinguished. Is the natural law a law given by God? Yes and no. Yes insofar as the natural law reflects the natures of things, and God, as creator, is the author of things and their natures. But the natural moral law is to that extent no different from what was said above about grass, trees, and squirrels. You don’t need to study theology in order to find out what is good or bad for grass, trees, and squirrels; indeed, you could be an atheist and know it. And the same thing is true for what is good or bad for usgiven our nature (at least to a large extent -- though there are religious obligations of a general kind under natural law given that the existence of God is knowable through unaided reason).
The natural law differs, then, from law that is directly given by God via a special revelation, as with the law given to Israel through Moses. Knowledge of the latter requires knowledge of certain specific historical events and of certain miracles associated with those events. The natural law is not like that; it is in principle available to all men simply by virtue of being rational and capable of knowing what is good or bad for them given their distinctive nature. Thus does Aquinas distinguish natural law from divine law. (He also distinguishes natural law from human law, which is or at least ought to be grounded in natural law and which determines, when it isn’t already clear, how natural law gets applied in concrete historical circumstances; and from eternal law, the archetypes or ideas in the divine mind according to which God creates things and which is thus the ultimate ground of the natural law, even if we can know much about the natural law merely by knowing human nature and without reference to God.)
It is thus an error to suppose that natural law arguments are inherently theological, at least in the sense many of their critics suppose. Though the natural law theorist would regard natural (as opposed to revealed) theology as part of a complete account of natural law, there are still large areas of morality which can be known without reference to theological claims of any sort, and these include the ones that are matters of the most intense controversy between natural law theorists and their critics (e.g. abortion and sexual morality). (I’ve said more about the relationship between theology and ethics hereand here.)
So, for the natural law theorist, certain things are “natural” for us in the sense of tending to fulfill those ends the realization of which constitutes our flourishing as the kinds of thing we are. But perhaps it is also natural for us -- in a different sense, the sense of being a weakness to which we are prone given the limitations of our nature -- for us to want to deny that we are subject to natural law. To that extent at least we are all natural lawyers, but of a rather sleazy kind -- seeking, not justice, but to find any way we can to get ourselves off the hook.