While applied ethics may appear to be a relatively recent development, serious philosophy has always had its applications. Since the time of Plato (fourth century B.C.E.), philosophers have been concerned with problems of living in the real world. Plato's Republic, for instance, concerned as it was with the nature of justice, discussed inescapable questions relevant to how one should live.

What is now known as applied ethics, however, came to prominence in the last third of the twentieth century, after a period in which the prevailing view, among Anglo-American philosophers at least, was that philosophy could not usefully be applied to practical problems. Instead, ethics had often been rejected as emotive and noncognitive in character or, in an effort to contribute to progressive clarity in moral discussions, philosophy devoted itself to metaethics or the analysis of ethical language. Applied ethics initially came to the...