A. JOHN SIMMONS is Commonwealth Professor of Philosophy and Professor of Law at the University of Virginia. He has been an editor of the journal Philosophy & Public Affairs since 1982. He is the author of Moral Principles and Political Obligations (1979), The Lockean Theory of Rights (1992), On the Edge of Anarchy: Locke, Consent, and the Limits of Society (1993), Justification and Legitimacy: Essays on Rights and Obligations (2000), Is There a Duty to Obey the Law? For and Against (with C.H. Wellman) (2005), Political Philosophy (OUP, 2008), and many other publications on topics in moral, political, and legal philosophy. He has edited the books International Ethics (1985) and Punishment (1995) and has chaired the University of Virginia's Philosophy Department and its Program on Political and Social Thought.