Hilary Putnam is Pearson Professor of Modern Mathematics and Mathametical Logic in the Department of Philosophy at Harvard University. Putnam has written extensively on the philosophy of mathematics, philosophy of natureal science, philosophy of language, and the philosophy of mind. The most recent publications is Pragmatism: An Open Question (Blackwell Publishers, 1995).
Peter Clark is Senior Lecturer in Philosophy at the University of St Andrews, Scotland. He co-edited Mind, Psychoanalysis and Science.
Bob Hale is Professor of Logic and Metaphysics at Glasgow University, Scotland. He is the author of Abstract Objects.