What can the wisdom of virtue teach us about imperfection, mediocrity, and the pursuit of happiness? Aristotle says that the virtues are the character traits needed for happiness. Rosalind Hursthouse’s analysis of this premise, called Plato’s requirement on the virtues, is made up of three theses, the first of which is the claim that the virtues benefit their possessor from within an ethical outlook. In this paper, I defend the neo-Aristotelian version of the view that morality is a form of enlightened self-interest. In the first section, I offer an analysis of Plato’s requirement on the virtues. In the second section, I respond to David Copp and David Sobel’s objection that the less-than-full virtues sometimes benefit their possessor more than the full virtues. In the third section, I respond to Nomy Arpaly’s objection that moral mediocrity benefits its possessor more than moral excellence. In the fourth section, I develop Aristotle’s argument that the full virtues benefit their possessor. My conclusion is that truly comprehending Plato’s first requirement can clear out of the way some misconceived criticisms of it, making room for a genuinely promising track to the rationality of morality.
