IAIN MACKENZIE is a Lecturer in Political Thought at the University of Kent, UK. He is the author of Politics: Key Concepts in Philosophy (2009), The Idea of Pure Critique (2004) and co-editor (with Robert Porter and Benoît Dillet) of The Edinburgh Companion to Poststructuralism (forthcoming).ROBERT PORTER teaches Cultural and Political Theory at University of Ulster, UK. He is the author of Ideology: Contemporary Social, Political and Cultural Theory (2006), Deleuze and Guattari: Aesthetics and Politics (2009) and co-editor (with Iain Mackenzie and Benoît Dillet) of The Edinburgh Companion to Poststructuralism (forthcoming).