Virtue signaling—the practice of highlighting what one takes to be one’s own moral superiority, often by loudly denouncing the character and comportment, including the speech, of other people—has become a dominant mode of rhetoric throughout social media and network television. Virtue theory, in contrast, is a teleological approach to normative morality concerned with how actions affect one’s soul or character. Historians of philosophy usually trace virtue theory to Aristotle’s Nicomachean Ethics, the first extant articulation of ideas such as that habits build character, and virtues...