 If the objections to intellectualism are warranted, Plato makes significant progress by having his character Socrates suppose that the soul has desires that are not always for what is good. This allows for the complexities of moral psychology to become an important issue in the account of virtue. That development is found in Plato’s mature moral theory. In the Republic, especially in its first four books, Socrates presents the most thorough and detailed account of moral psychology and virtue in the dialogues.