For nearly two centuries, “liberalism” has designated a variety of ideas and institutional arrangements, sharing at least a family resemblance and perhaps also an essential core. In advanced capitalist countries, the dominant theory and practice of politics nowadays generally are liberal. In some capitalist societies, like the United States, liberalism has been a dominant ideology from the beginning. Among political philosophers and moral theorists in the English-speaking world, liberalism has never been more ascendant than it now is. Part of the explanation for this phenomenon must lie with the enormous impression made by the work of some contemporary liberal philosophers. But their influence is itself explained, in part, by the undeniable appeal of liberal tolerance. Historically, liberals have sought to ensure tolerance by arguing for principled limitations on the state's – and also society's – power over individuals' lives and behaviors. In contemporary accounts, liberal philosophers have propounded the idea of neutrality with respect to “conceptions of the good.” On this understanding of the core liberal idea, the state – and, more generally, society through what Mill called “the moral coercion of public opinion” – should not seek to implement particular conceptions but should only guarantee that competing views, or at least those that are in any way controversial, be treated fairly. This contention is ostensibly at odds with Marxist accounts of the last state.