This is the last I shall write on this topic, I promise. I do not want to become morbidly fixated upon it, after all. But a few final observations have occurred to me. Some months ago, I admitted here that I find very little natural law theory persuasive, but granted that classical forms of the tradition are cogent given the religious and metaphysical assumptions with which they work; of attempts to forge an effective natural law theory without the support of those assumptions, agreeable to the temper of modernity, I was dismissive. In a subsequent column, I laid out some of the reasons why the late modern view of reality is one to which I think no natural law theory can successfully accommodate itself and made some provocative assertions on the limits of “purely natural” ethical reasoning. Both pieces provoked some attacks: some mild and judicious, some considerably more fierce, but none that (to my mind) convincingly addressed the concerns I voiced.

Perhaps some of that is my fault. Given the necessarily condensed nature of columns with word limits, I may have been guilty of a few cryptic formulations. At least, one of my critics seems to think I was arguing for the impotence of philosophical moral reasoning in order to promote the intellectual hegemony of theology. I suppose, therefore, that both my denial of the existence of any “master discourse” on ethical matters and my rejection of any strict division of philosophy from theology were less incandescently perspicuous than I had imagined they were. I seem also to have failed to make adequately clear that my skepticism regarding the power of a “purely natural” philosophy to establish the reality of a moral dimension in natural ends arises not from doubts regarding the powers of natural reason, but rather from doubts regarding the powers of philosophical dialectic when it artificially confines itself to “purely natural” principles.

Mind you, much of the disagreement vanishes if the central question is only whether, to borrow a line, “there is common ground between all human beings, and par­ticularly between religious believers and non-believers, on which moral disagreements can be rationally adjudicated.” I am not sure I could sneak so minimalist a definition of natural law theory past, say, the piercing eyes of Russell Hittinger; but, by all means, if we are talking only about principles upon which we all agree in advance, then only details remain.

I, however, do not believe everyone agrees on those principles anymore, even when it seems they might. I think traditional moralists today will inevitably find that any “natural” terms they employ have very different meanings for their interlocutors, and invite very different conclusions. And they will find also that no philosophical arguments simply from the evident natures of things will suffice to prove the validity of their presuppositions.

That is not really all that provocative a claim, so long as one remembers to distinguish principles from proofs. In my second column, I stated that purely natural philosophical arguments have “never, ever” succeeded in establishing “objectively true” moral conclusions. Again, though, apparently I should have been clearer. I was not denying the rational obviousness of a great many “in­nocuous” moral truisms—one ought not to torture babies, for instance, or one ought not to punish the innocent, and so on—but I certainly was denying that what is rationally obvious is always therefore some kind of objective fact that philosophical dialectic can prove to be true from a synthetic judgment about nature. The moral content—the imperative—in such principles resides nowhere within the ensemble of natural facts that philosophy can enumerate. These are truths that attest to themselves before an illuminated conscience, and one must have an immediate grasp of them to be capable of any ethical reasoning at all.

Anyway, argument is not necessary here. One need only supply an invincibly complete purely natural argument for some clear moral conclusion to prove me wrong, and this would not dismay me. I do not think that will happen, however, and right now my real interest lies elsewhere. I simply cannot shed the suspicion that many of us today fail fully to grasp the sole true intellectual achievement of modernity: the creation of a fully developed, imaginatively compelling, and philosophically sophisticated tradition of metaphysical nihilism.

My greatest failure in my second column, how­ever, seems to have been in neglecting to explain that, in providing a brief description of the late-modern, neo-Darwinian picture of nature, I never meant to accuse natural law theorists of suffering from a naive obliviousness to the sheer redness of nature in tooth and claw. The issue for me was never one concerning the violence of nature, of which everyone is perfectly well aware, but one concerning modernity’s overarching narrative—physical and metaphysical—of what nature is.

The late modern picture of reality is, culturally speaking, something altogether unprecedented. In the days of, say, Thomas Aquinas, there was no particularly cogent alternative to seeing nature as a rationally ordered continuum in which all things witnessed to a final good, at once cosmic and moral. Even if one did not concur with Thomas’ (often very questionable) moral judgments, one could scarcely reject many of his metaphysical presuppositions; and so one might not notice the covertly theological nature of those judgments. Not so now. The modern person’s failure to find a moral meaning in nature’s forms is not simply attributable to a perverse refusal to recognize objective truths. There is now a story that makes nihilism—in the technical sense of disbelief in any ultimate meaning or purpose beyond the physical—plausible and powerful.

With the rise of the mechanical philosophy, modern persons began to conceive of natural ends not as in­herent purposes but merely as useful functions. Even those who believed that the exquisite clockwork of the universe had been assembled by an intelligent designer still regarded physical nature as an amalgam of intrinsically aimless energies upon which order had been extrinsically imposed, and so not as a natural revelation of the divine logos pervading all things. Then, with the rise of Darwinism, and finally of an essentially mechanistic genetocentric neo-Darwinism, an entirely new and seemingly exhaustive account of physical order and causality came into being, one in which there were no such things as intrinsic natures, but only local coalescences of diverse and meaningless material forces.

Within this view of things, organisms are cohesive but farraginous assemblages of the various “desiring machines” (to use Deleuze’s phrase) that compose bodies and psyches. Not only is there no single universal rational form dictating the proper end of this or that individual organism; there is no single proper purpose inherent in any aspect of an organism. There is only a warring multiplicity of genetic and organic propensities and uses—temperamental, chemical, erotic, creative, destructive, and so on. Prescriptions regarding what tends towards the flourishing of distinct natural kinds refer, then, only to a proximate and pragmatic calculus of what works in general, but have nothing to say about what is morally incumbent upon any individual instance of life’s energies.

Now, of course, the late modern “naturalist” or “physicalist” view of reality suffers from innumerable logical lacunae, most particularly at the level of ontology; and there are phenomena it can never adequately explain, such as intentional consciousness. But a sufficiently complacent metaphysical nihilist can “logically” dismiss logic as a flawed instrument, crafted fortuitously by mindless forces, without any bad conscience. Happily for them, natural law theorists will only rarely find themselves arguing with anyone consciously committed to so extreme a naturalist perspective. In most persons there is enough moral sentiment and habit—enough nostalgia for the absolute—for them to be open to persuasion. But sentiment and habit are fragile and perishable things, and the nihilist narrative is far more tacitly pervasive than we are always aware.

This is because it is appealing. It is all part of the great ideological project of modernity. The metaphysical demotion of nature’s order from purposiveness to functionality is a license to believe that there is no meaning to life that we do not impute to it or—more excitingly—impose upon it. Metaphysical nihilism is a formula for a limitless voluntarism, the exhilarating adventure of the will to power. To many this seems like liberation from the tyranny of the absolute, and so the very form of freedom. To others, more traditionally inclined, it seems like cruel exile from participation in creation as a natural and supernatural order, and so slavery to nothingness.

All that can mediate between these two views of reality is the rhetoric of conversion—in all its philosophical, cultural, empirical, religious, and affective registers—but I know of no school of “purely natural” moral reasoning that can convince anyone but the already converted. Again, though, I am more than willing to be proved wrong.

David Bentley Hart is a contributing editor of First Things. His most recent book is Atheist Delusions: The Christian Revolution and Its Fashionable Enemies (Yale University Press).