Ethics is the branch of philosophy that tries to understand a familiar type of evaluation: the moral evaluation of people's character traits, their conduct, and their institutions. We speak of good and bad people, the morally right or wrong thing to do, just or unjust regimes or laws, how things ought and ought not to be, and how we should live. One part of the subject, metaethics, is concerned with what such judgments mean, what, if anything, they are about, whether they can be true or false, and if so what makes them true or false. The other part of the subject, normative ethics, is concerned with the content of those judgments: What features make an action right or wrong; what is a good life; and what are the characteristics of a just society? This entry will concentrate on normative ethics, though some comments on metaethics will be...