The term virtue is often used equivocally in both scholarly and ordinary discourse. The term is sometimes employed to mean whatever is morally good or appropriate. However, it has traditionally been used more precisely to mean certain qualities of character, or dispositions to choose actions, that are essential to living the right kind of life. As Aristotle defined it in the Nicomachean Ethics, virtue “is a settled disposition toward actions by deliberate choice.” According to Aristotle and those who have followed him, one acquires virtues by engaging in virtuous acts: “A man becomes just by doing just actions and temperate by doing temperate actions; and no one can have the remotest chance of becoming good without doing them.” He ridicules those who, “instead of doing ...