Moral philosophy seems well placed to claim the key role in theorizing about moral education. Indeed, moral philosophers have from antiquity had much to say about psychological and other processes of moral formation. Given this history, it may seem ironic that much systematic latter-day theorizing about moral education has been social scientific, and that some of the major trends in the field have been led by empirical or other psychologists. Moreover, while acknowledging the influence of such major past philosophers as Plato, Aristotle, and Kant on the primary modern movements of cognitive developmentalism, care ethics, and character education, some recent social scientists have called for the development of a "psychologized morality" in the interests of an even more leading role for psychological research in the theory of moral formation. In this essay, David Carr surveys and critically evaluates these trends in theorizing moral education.