Subjectivist theories such as expressivism can explain why humans make the ethical judgments they do, but only by emptying morality of objective authority
There is a kind of argument from moral knowledge also implicit in Angus Ritchie’s book From Morality to Metaphysics: The Theistic Implications of our Ethical Commitments (2012). Ritchie presses a kind of dilemma on non-theistic accounts of morality. Subjectivist theories such as expressivism can certainly make sense of the fact that we make the ethical judgments we do, but they empty morality of its objective authority. Objectivist theories that take morality seriously, however, have difficulty