Solomon Feferman has been a Professor of Mathematics and Philosophy at Stanford University since 1956, from which he retired in 2004. He is a Fellow of the American Academy of Arts and Sciences, was President of the Association for Symbolic Logic in 1980–2, and was the recipient of the Rolf Schock Prize for Logic and Philosophy in 2003. Feferman was editor-in-chief of the Collected Works of Kurt Gödel (1986–2003). Charles Parsons holds an AB (mathematics) and PhD (philosophy) from Harvard University and studied for a year at King's College, Cambridge. He was on the faculty at Harvard University from 1962–65 and 1989–2005 and at Columbia University from 1965–89. His publications are mainly in logic, philosophy of mathematics, and Kant. He was an editor of the posthumous works of Kurt Gödel (Collected Works, Volumes III–V). Stephen G. Simpson is a mathematics professor at the Pennsylvania State University. He has lectured and published widely in mathematical logic and the foundations of mathematics. Simpson is the developer of the foundational program known as Reverse Mathematics and the author of Subsystems of Second Order Arithmetic, 2nd Edition.