On behalf of the moral realist

The overarching thesis of Clark-Doane's gripping book (Clarke-Doane, 2020) is that despite the many deep similarities between the views, realism about mathematics is a tenable position whereas moral realism is not. The closing chapters develop two main arguments for this thesis. The Argument from Safety (as I'll call it) wields a general epistemological principle to argue that moral realism leads to moral skepticism and is thus untenable, whereas mathematical realism has no such consequence. The New Open Question Argument (as Clarke-Doane calls it) argues in the alternative that even if we could know all the moral facts as the realist conceives them, the most important moral questions would still be open, and hence that these moral questions are not questions about the facts at all.

In what follows I respond on behalf of the moral realist. For definiteness I focus on the sort of full-strength realism that takes moral questions to concern a domain of fact that is not only mind-independent but irreducibly normative and therefore sharply distinct from the facts with which the positive sciences are concerned (Enoch, 2011). My moral realism endorses what Clarke-Doane calls objectivity — the idea that every non-vague moral claim is determinately true or false in the one true moral universe — and so rejects most forms of relativism. It also includes the antiskeptical thesis that the moral facts are often knowable, not just in principle but in ordinary ways. If Clarke-Doane's arguments make trouble anywhere, they should make trouble here. I'm going to argue that no trouble has been made.