Darwinian ethics and error

Suppose that the human tendency to think of certain actions and omissions a s morally required - a notion that surely lies at the heart of moral discou rse - is a trait that has been naturally selected for. Many have thought th at from this premise we can justify or vindicate moral concepts. I argue th at this is mistaken, and defend Michael Ruse's view that the more plausible implication is an error theory - the idea that morality is an illusion foi sted upon us by evolution. The naturalistic fallacy is a red herring in thi s debate, since there is really nothing that counts as a `fallacy' at all. If morality is an illusion, it appears to follow that we should, upon disco vering this, abolish moral discourse on pain of irrationality. I argue that this conclusion is too hasty, and that we may be able usefully to employ a moral discourse, warts and all, without believing in it.