How we achieve a good life and what it entails are the questions of ethics that have existed since the beginning of time. But what if these questions are unnecessary? Today, psychology, brain research, and evolutionary biology can explain more accurately than ever what determines our behavior and guides our moral judgments. Through his thought experiments, Kwame Anthony Appiah familiarizes us with the idea that philosophical ethics and empirical science can only explore the right way of living together. Accessible, clear, and striking in its sparkling sharpness, he makes it evident where the boundaries of both lie: the new empirical moral research can only tell us what we actually do and feel through its experiments, but not what we ought to do or feel. Ethics—and every person seeking a virtuous life—goes astray when it ignores human behavior as it truly is.