Nietzsche had the insight that those, like George Eliot (Mary Anne Evans), who think they can have morality and moral duty without a religious foundation are deluded. “They are rid of the Christian God and now believe all the more firmly that they must cling to Christian morality.” Nietzsche thought there are no moral facts, precisely because there are no theological ones. The moral argument takes Nietzsche’s assertion as one of its premises: if there is no God, then there are altogether no moral facts. But contra Nietzsche it also urges that we have, in our moral experience, good reason to suppose that there are indeed moral facts.

Such arguments come in numerous forms—without a lawgiver there’s no moral law, prudential considerations, requirements of moral knowledge—but Kant’s is one of the more sophisticated: If there’s no God, then the moral law makes objective demands that are not possibly met, namely, that the moral good of virtue and the natural good of happiness embrace and become perfect in a “highest good.” But then the demands appear to be empty, and in the face of such an antinomy, we might come to think of moral requirements as null and void. For Kant, though God is not the author of the moral law, he is required as a sort of Director of the screenplay. If death is the end, he also argued morality wouldn’t seem to matter as much as it should.

Linville’s argument will instead focus on this: theists can, where naturalists can’t, offer a framework on which our moral beliefs may be presumed to be warranted. In particular, the naturalist’s commitment to a Darwinian explanation of certain salient features of human psychology presents an undercutting defeater for our moral beliefs taken as a whole. This argument is thus chiefly epistemological in nature, and seldom strays from the discipline of metaethics.

Wilson and Ruse have suggested ethics to be an illusion fobbed off on us by our genes in order to get us to cooperate. The pressures of natural selection, on their view, have had an enormous influence on human psychology, including the hardwiring of epigenetic rules, widely distributed propensities to believe and behave in certain ways, which have developed through the interaction of human genetics and human culture. Such rules give us a sense of obligation because of their adaptive value, not because they detect any actual moral obligations. Objectivity in morality is illusory, a useful fiction. Ruse thinks Darwin’s theory complements Hume’s subjectivism.

On Hume’s view, belief in objective moral properties is at best unwarranted, and talk of them is in fact meaningless. The only fact of the matter we find in moral judgments is an object of feeling, not of reason. It lies in ourselves. The mind, as Hume put it, has “a great propensity to spread itself on external objects,” so that the subjective feelings that, given our constitution, result from such contemplation of some act, are mistaken for perceptions of objective properties of the act itself.

Let’s call the combination of naturalism and an overall Darwinian account of the origin of the species evolutionary naturalism (EN); according, then, to one like C. S. Lewis, on EN, the dictates of conscience are little more than an aggregate of subjective impulses which, although distributed widely throughout the species, are no more capable of being true or false than a vomit or a yawn.

An argument—call it the argument from evolutionary naturalism (AEN)—thus emerges from such considerations:

1. If EN is true, then human morality is a by-product of natural selection.
2. If human morality is a by-product of natural selection, then there are no objective moral facts.
3. There are objective moral facts.
4. So, EN is false.

This isn’t an argument for God, but for the falsity of EN. Also, naturalism doesn’t entail Darwinism, but Darwinism seems to be the only game in town. Linville’s primary focus will be to consider objections to the first two premises. He realizes there are plenty of anti-realists out there, but wishes to focus on realists who try to ground their realism in EN. One might object to the first premise by denying that natural selection is solely or even partly responsible for the emergence of human morality. And the second premise might be accused of a common fallacy by moving so quickly from an account of the origins of human morality to the assertion that its claims to objectivity are false. What might the evolutionary naturalist say about the possible connections between the workings of natural selection and the truth of our moral beliefs?

AEN and the genetic fallacy

The second premise initially appears to be guilty of the genetic fallacy; identifying the source of a belief is generally not evidence of its falsity. But sometimes identifying the origins of a belief is relevant to a consideration of its truth, as in cases where it can be shown that the explanation of someone’s belief is epistemically independent of whatever would make the belief true. (Like forming a belief about the number of people in a room by a random drawing.)

Might we offer a similar evolutionary argument for moral skepticism? Sober suggests it’s a tall order because we’d have to identify the processes of moral belief formation and the would-be truth-makers for moral beliefs, and then show such processes and truth-makers to be independent. Call this the Independence Thesis.

Of course the Independence Thesis doesn’t entail that morality is an illusion, but merely that our moral beliefs are probably false. But we need not argue for the falseness or probable falseness of our moral beliefs. Nor is it necessary to argue for the truth of the Independence Thesis. It is one thing to suggest that there are positive reasons for asserting epistemic independence, and quite another to say we lack any reason for thinking that a relevant dependence relation obtains. We would have a reason for thinking there is such a relation just in case the best explanation for a person’s having a given belief essentially involves the truth of that belief. It seems that a plausible Darwinian yarn may be spun in such a way as to offer a complete and exhaustive explanation of our various moral beliefs without ever supposing that any of them are true.

It was no background assumption of the evolutionary explanation of our moral beliefs that any actual moral rightness or wrongness existed in the ancestral environment. When we look at the animals, we explain their behavior and the impulse toward their behavior by appeal to adaptiveness. Moral properties are not included in the cast of characters. On a Darwinian story, conscience is what arises in a social creature once the social instincts are overlain with a sufficient degree of rationality.

Arguably, given an evolutionary account of human moral beliefs, there is no reason for thinking that a relation of epistemic dependence obtains, and so, given an evolutionary account, belief in moral facts is unwarranted. If our moral beliefs are without warrant, then they do not amount to moral knowledge. Linville thus modifies (2) in AEN to

(2*): If human morality is a by-product of natural selection, then there is no moral knowledge.

An evolutionary account serves to undercut whatever warrant we might have had for our moral beliefs, and if they lack warrant, they are not items of knowledge.

Wilson and Ruse think Darwinism poses a rebutting defeater for our moral beliefs, as well as for moral realism itself. Linville instead thinks the proponent of AEN might back off from the stronger claim that Darwinism entails that there are no moral facts, speaking instead of whether we are warranted in our ordinary moral beliefs. In this way AEN becomes an epistemological argument for moral skepticism. As Richard Joyce observes, the conclusion that our moral beliefs are “unjustified” is “almost as disturbing a result” as an argument for the actual falseness of those beliefs.

On the suggestion that Darwinism presents us with an undercutting defeater for moral beliefs, (3) becomes

(3*): There is moral knowledge,

and this takes us to the conclusion that

(4) EN is false.

What we lack is some reason for thinking that the adaptiveness of a moral belief depends in any way on its being true. Linville turns the tables on Sober. Instead of Sober’s suggestion that the AEN defender must show that moral beliefs are independent of any truth-makers, perhaps the onus is on those who assert dependence. Why, given EN, should we suppose the world to include anything more than natural facts and properties and our subjective reactions to those properties?

Photo: "Charles Darwin" by PhOtOnQuAnTiQuE. CC License.