Cognitivism, A Priori Deduction, and Moore

Abstract

By “cognitivism,” I mean the view that ethical sentences make claims about how things are and that what allows ethical sentences to play this role is that they contain ethical predicates which apply to X—be X an action, a situation, a person, a possible world, or . . . —in virtue of how X is. Cognitivism, on this understanding, implies that there are ethical properties in the sense of ways things might be in virtue of which one or another ethical predicate applies. In consequence, cognitivists take at face value our natural expression of the supervenience of the ethical on the nonmoral or natural in terms of situations, actions, people, worlds, and so on, that are exactly alike in nonmoral terms having to be exactly alike ethically. The talk of ethical likeness is taken literally—to be alike ethically or morally is to share an ethical property—and not reworked as some kind of constraint on prescriptions or on the expression of attitudes, or some such, that must be met if the prescriptions or attitudes are to count as ethical. Many years ago, Simon Blackburn pointed out that supervenience so understood means that cognitivists are committed to a necessitation doctrine: the nonmoral or natural way things are necessitates the ethical way things are. He argues that this is bad news for cognitivists because it goes against powerful considerations that go under the title of the open question argument in one or another of its guises to the effect that no matter how much information you have bearing on, say, a contemplated course of action, framed without the use of moral terms, it