Moral theory is no substitute for virtue, but virtue is no substitute for moral theory. Many critics of moral theory, with Richard Posner being one prominent recent example, complain that moral theory is too abstract, that it cannot generally be used to derive particular rights and wrongs, and that it does not improve people’s characters. Posner complains that it is thus of no use to legal theorists. This article defends moral theory, and to some degree, philosophical inquiry in general, against such pragmatic complaints. I argue that the primary goal of moral theorizing is not pragmatic, but theoretical. Moral theory aims at explanation, at answering certain kinds of questions about morality. Moral theory is meant to deepen our insight into morality but, to count as deepening our insight, it need not provide a formula for calculating what to do in a particular circumstance, nor must it make us more virtuous. I provide an account of the scope and nature of explanation provided by moral theory as well as an account of why such explanations can be worth having, even if they were to have few pragmatic consequences.