 One obvious strategy to adopt in defence of morality is to claim that a person’s well-being is in some sense constituted by their virtue, or the exercise of virtue, and this strategy was adopted in subtly different ways by the three greatest ancient philosophers, Socrates, Plato, and Aristotle (for a modern defence of the view, see Bloomfield (2014)). At one point in his writings, Plato appears to allow for the rationality of moral self-sacrifice: the philosophers in his famous ‘cave’ analogy in the Republic (519–20) are required by morality to desist from contemplation of the sun outside the cave, and to descend once again into the cave to govern their fellow citizens. In the voluminous works of Aristotle, however, there is no recommendation of sacrifice. Aristotle believed that he could defend the virtuous choice as always being in the interest of the individual. Note, however, that he need not be described as an egoist in a strong sense—as someone who believes that our only reasons for action are grounded in our own well-being. For him, virtue both tends to advance the good of others, and (at least when acted on) advances our own good. So Aristotle might well have allowed that the well-being of others grounds reasons for me to act. But these reasons will never come into conflict with reasons grounded in my own individual well-being.