U.C. Philosophy Department
Association for Symbolic Logic
Gottlob Frege
Bertrand Russell, Russell Archives
David Hilbert, Foundations of Math, 23 Unsolved Problems
Kurt Gödel Gödel Society
Rudolf Carnap
Alan Turing Home Page, Turing Machines
Emil Post
Alonzo Church
Jon Barwise
Aristotelian Logic
Stoic Logic
Porphyry
Mediaeval Logic and Philosophy
Mediaeval Source Book
Peter of Spain
William of Ockham
John Buridan
Antoine Arnauld
Boolean Logic
The journal
Books
Sierra Club