Michael Ruse is an anti-realist, in some ways like Mackie, but in other ways different. He thinks ethics is an illusion put in place by natural selection to make us good cooperators. Ruse is a moral skeptic. He does not think the sense of right and wrong has a justification at all. It’s an illusion foisted on us by our genes, like a mirage in the desert.

Yet Ruse is quite optimistic that our moral lives will not be affected by the kind of skepticism he endorses. Hare is skeptical of this, thinking we surely need some kind of justification for morality to answer the “normative question” of the first chapter. Not everybody is consistently moved by the forces of natural selection to cooperate in the way morality requires. Moral obedience is fragile. We do find precursors of the moral sentiments in our non-human ancestors, but we also find defection, and we have inherited both of these tendencies. We are by nature, in this sense, a mixture. But this means we need support from our cultural sources not only for our beliefs about what morality requires, but for our beliefs about why we should comply with it, or endorse it, why it’s valid as a demand on us. There’s evidence in the psychological literature that the force of the moral demand can be undermined by teaching, as Ruse does, that objective morality is an illusion. Saying that ethics is an illusion put in place by natural selection to make us good cooperators is likely to have the same undercutting effect as an egoist ethical theory has on economics students, particularly when morality might call for a sacrifice.

But is it just an unfortunate truth that morality is an illusion? What arguments does Ruse have for his skepticism? He has basically two, and they are versions of the same arguments we saw in Mackie. But here is the irony. Ruse ought not to accept either of them any longer because of differences from his mentor that he has come to have in other parts of his theory.

First, the argument from relativity. Ruse’s form of the argument makes a significant shift from the factual to the counterfactual. Ruse embodies a pendulum swing away from Mackie back to human universals, encoded in our genes (with environmental triggers). He appeals to what he calls “our shared psychological nature,” which includes a sense of right and wrong. So his argument from relativity is counterfactual. We could have had a quite different morality if our evolutionary history had been different. Since evolution could have taken a different path, there can’t be an objective set of values that lies behind our moral practice.

But for a divine command theorist this is not a successful objection. God could use evolution to produce the kind of creatures God wants to have, and this does not deny “random” mutation of the kind that Darwinian evolution proposes. Ruse concedes this, and agrees that a Christian can, consistently with science, “be committed to a form of what is known as the ‘divine command theory’ of metaethics.” But then the fact that humans could have evolved differently does not give us reason to think there is no objective value. Perhaps God willed us to evolve to recognize the values there actually are, and gave us commands to supplement the limits of this evolutionary history.

Ruse’s version of the argument from queerness is similarly undercut by his later concessions. He doesn’t use the term ‘queer’ but he does insist that it’s biological theory that requires us to take the skeptical position about justification. At the causal level, he thinks what’s going on is probably individual selection maximizing our own reproductive ends, and there’s no room here for objective rightness and wrongness. But Mackie was an atheist who thought theism was a “miracle.” Ruse, on the other hand, aims to expose the over-reaching character of some contemporary militant Darwinism that wants to turn science into metaphysics and to make science the arbiter of all truth. Darwinism, he holds, should not try to say everything. Whether there is or is not a God Ruse says he does not know, and science doesn’t tell him. Such claims go beyond science. He says in light of modern science someone can be a Christian and that he sees no arguments to the contrary.

To be consistent, though, Ruse should say the same of objective morality. Mackie’s argument from queerness required the premise that anything that has causal relations with the world must be accessible to science. Ruse at least sometimes now wants to deny this, and if he denies it then the foundation of the argument from queerness disappears. There’s a tension in Ruse’s thought that can be resolved by rejecting the skeptical hold-over from the less generous views of his mentor.

Here is a general principle worth emphasizing. Antagonism to realist claims in ethics or theology that made sense against the background of a thoroughgoing reductive empiricism makes no sense once that kind of empiricism is rejected.

Image: "Australopithecus sediba" by B. Eloff. Courtesy Profberger and Wits University who release it under the terms below. - Own work, GFDL, https://commons.wikimedia.org/w/index.php?curid=10094681