Moral Realism vs. Evolutionary Biology?
To review Thomas Nagel's new book for the Mises Daily seems at first sight a misplaced endeavor. The book has nothing to say about libertarianism or Austrian economics; moreover, Nagel's own political views are decidedly non-libertarian. He wrote the most influential critical review of Nozick's Anarchy, State, and Utopia, and he rejects Lockean theories of property ownership, instead viewing property rights as conventional.1 Nevertheless, one chapter in the book raises issues of profound concern to anyone interested in political philosophy, and it is for this reason that I wish to comment on it here.
Suppose one says that it is wrong to initiate force against other people. What does it mean to say that this claim is true? Are moral judgments just personal preferences, or are they more than this? Mises favored the former alternative. We can judge objectively that certain actions are suitable means to achieve a goal, but ultimate value judgments cannot be assessed as rational or irrational.
To apply the concept rational or irrational to the ultimate end chosen is nonsensical. We may call irrational the ultimate given, viz., those things that our thinking can neither analyze nor reduce to other ultimately given things. Then every ultimate end chosen by any man is irrational. It is neither more nor less rational to aim at riches like Croesus than to aim at poverty like a Buddhist monk. (Human Action, p. 880)
To many, though, this seems inadequate. It's isn't only that we prefer not to murder innocent children, for example: it really is wrong to do so, in a sense not reducible to people's choices or anything else. (Mises would I think say that the rule against murder, combined with other moral rules, is a means by which we can achieve a society of peace and prosperity, which nearly everyone wants; but that this latter preference is an ultimate judgment of value that is neither true nor false.)
As Nagel says,
Instead of explaining the truth or falsity of value judgments in terms of their conformity to our considered motivational dispositions or moral sense, as the subjectivist does, the [moral] realist explains our moral sense as a faculty that aims to identify those facts in our circumstances that count for and against certain courses of action, and to discover how they combine to determine what course would be the right one, or what set of alternatives would be permissible or advisable and what others ruled out. (p. 102)
In brief, morality is a matter of finding out, not choosing or feeling.
Nagel thinks it is coherent to reject moral realism, but nevertheless he finds the view more compelling than its subjectivist competitors:
To be sure, there are competing subjectivist explanations of the appearance of mind-independence in the truth of moral and other value judgments.… There is no crucial experiment that will establish or refute realism about value … the realist interpretation of what we are doing in thinking about these things can carry conviction only if it is a better account than the subjectivist or social-constructivist alternative, and that is always going to be a comparative question and a matter of judgment, as it is about any other domain, whether it be mathematics or science or history or aesthetics. (pp. 104–5)
But is not moral realism exposed to a decisive objection, famously pressed by John L. Mackie? In suggesting that values are "out there" in the world, rather than human preferences or sentiments, does not the moral realist postulate "ontologically queer" abstract objects, unlike anything else in the universe?
Nagel convincingly shows that this objection rests on a misunderstanding. Moral realism does not hold that there is, in addition to ordinary objects, a special class of metaphysical objects called "values." Rather, its contention is that moral reasons do not require reduction to something else in order to count as legitimate.
The dispute between realism and subjectivism is not about the contents of the universe. It is a dispute about the order of normative explanation. Realists believe that moral and other evaluative judgments can often be explained by more general or basic evaluative truths, together with the facts that bring them into play.… But they do not believe that the evaluative element in such a judgment can be explained by anything else. That there is a reason to do what will avoid grievous harm to a sentient creature is, in a realist view, one of the kinds of things that can be true in itself, and not because something else is true. (p. 102)
If Nagel spurns metaphysical objects, does this suffice to vindicate moral realism? A common objection holds that even if objective reasons of the sort Nagel favors are not metaphysical in a dubious sense, they remain inconsistent with the naturalistic outlook on the world required by evolutionary biology. Allan Gibbard has presented an influential account of this contention:
How could we be in any position to intuit moral truths, or normative truths in general? No answer is apparent in the biological picture I sketched. Non-natural facts are absent from the picture, and so are any powers to get at non-natural truths by intuition. Interpreting the natural goings-on as thoughts and judgments doesn't change this. If moral knowledge must depend on intuition, we seem driven to moral skepticism.2
The objection, in brief, is this: Evolution can account for our attraction to pleasure or aversion to pain. But it knows nothing of objective reasons: how could a faculty for grasping them have evolved? Unless, then, we abandon science, we must give up moral realism. Nagel considers a paper by Sharon Street, arguing to this effect, and he is much impressed by it. But he takes the argument in a different direction from that taken by Street and her fellow naturalists. If moral objectivity is inconsistent with our current picture of evolution, that is a reason to think that this picture gives us an incomplete and inadequate understanding of the world:
I agree with Sharon Street's position that moral realism is incompatible with a Darwinian account of the evolutionary influence on our faculties of moral and evaluative judgment. Street holds that a Darwinian account is strongly supported by contemporary science, so she concludes that moral realism is false. I follow the same inference in the opposite direction: since moral realism is true, a Darwinian account of the motives underlying moral judgment must be false, in spite of the scientific consensus in its favor. (p. 105)
If Nagel is right, it makes sense to speak of objective moral reasons; but what must the universe be like for this to be true? The question must not be misunderstood. It is not, what in the universe makes moral reasons objectively true? To ask this would be precisely to reject Nagel's chief contention, that nothing makes moral reasons true: they require no justification from something else. Rather, the question to be addressed is, what must the universe be like if there are free-standing moral reasons of the kind Nagel accepts?
One alternative to the Darwinian view Nagel finds untrue to the moral facts is theism, but to this he is temperamentally averse. He prefers what he calls a teleological view.
According to the hypothesis of natural teleology, the natural world would have a propensity to give rise to beings of the kind that have a good — beings for which things can be good or bad. (p. 121)
Nagel's teleological view is by no means confined to value, and other chapters of the book apply the teleological approach to subjective consciousness and cognition as well.
But even though natural selection partly determines the details of the forms of life and consciousness that exist, and the relations among them, the existence of the genetic material and the possible forms it makes available for selection have to be explained in some other way. The teleological hypothesis is that these things may be determined not merely by value-free chemistry and physics but also by something else, namely a cosmic predisposition to the formation of life, consciousness, and the value that is inseparable from them. (p. 123)
Nagel's argument is frankly speculative, but in the best sense; it opens to our consideration new possibilities, developed in an imaginative and deep way. Nagel is a great philosopher, and he could with justice say to his naturalist adversaries,
There are more things in heaven and earth …
Than are dreamt of in your philosophy.