Tom Ricketts is Professor of Philosophy at Pittsburgh University. He is the author of numerous articles on the development of analytic philosophy, especially Frege, Wittgenstein and Carnap.
Michael Potter is a Reader in the Philosophy of Mathematics at Cambridge University and a Fellow of Fitzwilliam College. He is the author of Wittgenstein's Notes on Logic (2009), Set Theory and its Philosophy (2004) and Reason's Nearest Kin (2000).