David Edmonds is an award-winning documentary maker for the BBC World Service. He is the author or co-author (with John Eidinow) of several books, including Wittgenstein's Poker (short-listed for the Guardian First Book Award), Bobby Fischer Goes To War (long-listed for the Samuel Johnson prize), and Rousseau's Dog (about the relationship between Jean-Jacques Rousseau and David Hume). He is currently a Research Associate at the Uehiro Centre for Practical Ethics at Oxford University and a Contributing Editor for Prospect Magazine. Nigel Warburton is Senior Lecturer in Philosophy at the Open University and author of several introductory philosophy books, including the bestselling Philosophy: The Basics and Philosophy: The Classics. His latest book is A Little History of Philosophy. He also regularly teaches courses on aesthetics at Tate Modern, and runs several weblogs including virtualphilosopher.com and artandallusion.com.