The late Bertrand Russell, English philosopher and mathematician, was a Fellow of Trinity College, Cambridge University, where he taught for many years. He also lectured widely in the United States. Winner of the 1950 Nobel Prize for Literature, he is the author of many books including the influential Principia Mathematica, with Alfred North Whitehead, and The Autobiography of Bertrand Russell 1872-1967, published in three volumes. John Perry is H.W. Stuart Professor of Philosophy at Stanford University and co-editor of Oxford's Introduction to Philosophy, Second Edition.