Before anything else I must record my gratitude to you for inviting and publishing Matthew O’Brien’s review of my new book, Constitutional Illusions & Anchoring Truths: The Touchstone of the Natural Law. I can’t imagine a better review being written anywhere. Apart from the praise (for which I’m quite grateful) the review gives the most precise account I’ve yet seen of what exactly is in the book; and the criticism is concentrated on the heart of the matter: on the understanding of natural law that runs through the book.

This was also the kind of review from which people on all sides could learn as one sees the fuller argument unfold. And in that spirit—with that purpose in mind—I’d like to raise some questions in turn for Matt O’Brien, if I can turn back on him some of the serious questions he raised about my argument. The most serious criticism he offered dealt with what he called, fairly enough, my “eclectic” blending or what he described as my “fusionist account” of the natural law, one which draws upon Aristotle, Aquinas, Kant and, yes, Lincoln. He is quite dubious about what he sees as a Kantian strain seeking to find the ground of our moral judgments in “the laws of reason.” The anchoring proposition in the laws of reason is of course the law of contradiction, and the test then of any proposition claiming the standing of a necessary truth, a first principle, is that it cannot be contradicted.

O’Brien regards that as altogether too confining, though it would seem to come along with the whole package if we understand the logic that has ever attached to “axioms” and “first principles.” John Finnis, a close student of Aquinas, remarked on the good of knowledge, as a good known per se nota, a truth to be grasped as true of necessity: that it is “presupposed in all demonstrations … and has as much title to be called ‘objective’ as any other proposition whose contradictory is inevitably falsified by the act of asserting it.” I don’t think Finnis would strike O’Brien as dangerously “Kantian” because he too seeks the grounds of our moral judgment in axioms that cannot be rejected without falling into incoherence.

But O’Brien is dubious about notions of seeking “maxims” fit to be installed as universal rules. He points out that in the play of normal life people have many reasons for doing what they do. And so, as he says, “the imperative to universalize ‘one’s maxim’ is forceless without substantive criteria to determine which maxims”:

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To have substance, morality needs to go beyond mere rational consistency and find its grounds in the form of “rational animality,” as Aristotle and Aquinas saw … [And earlier:] The Kantian aspiration to squeeze morality out of rational consistency is unworkable because the categorical imperative to “universalize” the maxim of one’s action is an empty formalism, as critics from Hegel to Anscombe have shown.

Of course the construction is formal; but when we apply the principles to practical cases we can draw propositions that are concrete, precise, quite freighted with substance, and not the least hazy. I should point out that nothing in this apparatus of reasoning could tell us what counts as hurt or harm among human beings. For that we need to be aware of life as lived. But once we are aware of a harm that calls out for justification, the principles of justification kick in with their real force. As Daniel Robinson has remarked in this vein, “Merely empirical content has no permanent address. It gains residence in the epistemic court by way of general concepts—code for ‘form.'” On the matter of “maxims”: Yes, people have many reasons for what they do, but when they are set upon, they will demand from their tormentor the justification for what was done to them, and I don’t think we will find people settling in so affably with the explanation, “Well I had many motives, high and low, serious and fleeting.” We would want to know the reason, or the maxim, that the actor regarded as decisive, when he acted upon us.

I do confess that I have drawn from Aristotle what I think has been most enduringly true in his writing, and so I have not followed Aristotle on biology or his conclusions about slavery. In the same way I’ve drawn what has struck me as resoundingly right in Kant, persuaded that I could do that without annexing for myself the parts of Kant that don’t strike me as especially illuminating or apt. The test will come in the application. And that is the point at which I would do the pivot and put the question back to Matt O’Brien. He and Robert George have been kind enough to point out, as a defining mark in my own work, the tendency to be rich in the furnishing of examples: the examples that illustrate, and the examples that test the argument. In a contrast, Matt thinks that, with my invocation at times of Kant, I run the risk of falling into abstraction and empty formalism. And yet the irony is that his own commentary, with its references to Kant, had itself a certain airy quality of abstractness. I would propose, then, this gentle exercise to test the matter at issue here.

Let us take up as an active possibility what O’Brien merely suggests: that accomplished philosophers such as MacIntyre and Anscombe, freed from my perspective, may offer in any practical case a sounder version of natural law, with a sounder judgment on the things that are just or unjust, right or wrong. Let’s try that. Let us take two of the critical problems I dealt with in the book, and I’d invite Matt to show how any of these writers—or any theory he would propose—would offer a sounder judgment, with a more satisfying set of reasons than the judgments I had brought forth, with the reasons that produced them.

The first case could be that argument in principle against racial discrimination as I have cast it in my writings going back to First Things (1986) and The Philosopher in the City (1981). I have argued that the wrong here is to be found in a notion of racial “determinism”—the claim that we are controlled or “determined” in our conduct by “race.” It assumes that, if we know the race of any person, we can draw then some telling inferences about their goodness or badness as persons—whether their presence in the neighborhood or the firm will improve the place or degrade it, whether they deserve rewards or disabilities. But every one of us could be said to be a member of a race. And if race exerts a deterministic control over our acts, then none of us would be responsible for his own acts. None of us could plausibly be punished then for the wrongs we do—or properly receive credit for our accomplishments. Indeed, as I’ve said, if these acts of racial discrimination are not wrong, nothing literally could be right or wrong, for the language and logic of moral judgment would dissolve. Moral words would lose their meaning.

The second case involved those matters recognized instantly by ordinary folks as facts wholly wanting in moral significance, facts that can supply no ground of moral judgment. We do not draw moral inferences about the goodness or badness of people, their worthiness or want of merit, on the basis of things like their height and weight, their color—or their affliction with disabilities such as Down’s syndrome or deafness. As I sought to show in the chapter on natural law, this argument, too, can find its ground as well in “the laws of reason,” for we simply reject the notion that any of these attributes—height, weight, disability—can exert a deterministic force over the moral character of any person. Wherever we are in the world, I submit that it would be wrong to let the withdrawal of medical care hinge on the moral conclusion that a life afflicted with deafness or Down’s syndrome is a “life not worth living.”

Any move to assert “determinism” in either case falls into the same incoherence: Either one would deny the essential freedom of the moral actor to choose his own path of action. That claim encounters its denial at every turn because it keeps falling into self-contradiction—the contradiction touched on by Robinson when he raised the question of whether we are “free to reject the determinist thesis.” And we remind ourselves that, if we have in hand propositions that cannot be denied without falling into contradiction, they will be true, perforce, in all places. And so, as Kant says, they will hold true for “all rational creatures” wherever they are found. Hence the claim that it would be wrong in all places to withdraw medical treatment from the deaf, or from those afflicted with Down’s syndrome, on the claim that people afflicted with these conditions have lives “not worth living.”

And that brings us to the threshold of what might be an interesting experiment. We could take from either one of these arguments—the argument in principle against racial discrimination, or the argument in principle about those facts “wholly wanting in moral significance”—the wrongness of withholding care from a patient on the basis of his deafness or Down’s syndrome. Here is the problem: Could O’Brien offer a better, or more compelling account of the wrong in these cases if he drew on any of the writers he offers as a corrective to the brand of natural law I’ve set forth in the book? Might MacIntyre or Anscombe, or any of these other writers we both esteem, offer a more satisfying account of natural law—and a sounder judgment in rendering a just decision in these cases? Let’s make sure that this account, or judgment, is not dependent on claims that are merely probabilistic and which may not hold true from one case or place to another. And let’s make sure that it doesn’t depend merely on generalizations about our fellow humans, which may not hold true all the time. With those concerns in mind, I wonder if we can pursue the conversation launched nicely by Matt O’Brien’s review.