We live in an age of deep ideological and moral conflict, not only in politics but in social and political theory. Whatever might be one’s own convictions about the ultimate truth of the matter, it is not one on which all reasonable citizens will converge: as far as public moral reasoning goes, there are a number of reasonable ways of ordering social and political institutions. Each is convinced that his political views represent the truth, but to your neighbor they are errors. In the midst of this, mainstream political philosophy continues to spin out endless rationalizations of the theorist’s ideological convictions. What truly flummoxes contemporary political philosophy is how to seriously and productively theorize about a deeply morally diverse society. Given that this is a defining feature of our time, it is hard to overestimate how devastating a failure this is. --Gerald Gaus