Steven Pinker is a cognitive psychologist at Harvard. His best-selling books include "The Stuff of Thought" and "How the Mind Works." His wife, Rebecca Goldstein, is a philosopher and novelist who is particularly drawn to the great 17th century philosopher, Spinoza. Goldstein's latest book is "36 Arguments for the Existence of God." Both Goldstein and Pinker are atheists, and they talk with Steve Paulson about the debates pitting reason against faith.