Our day-to-day beliefs often come from established theories, but what about beliefs based on theories in progress? A new book asks literary and scientific thinkers about what they believe but cannot prove.

Guests:

John Brockman, editor, What We Believe But Cannot Prove: Today's Leading Thinkers in Science in the Age of Certainty; author and literary agent; publisher and editor of Edge.org

Richard Dawkins, evolutionary biologist; professor of the public understanding of science at Oxford University; author of many books about science and evolution, including The Selfish Gene and most recently, The Ancestor's Tale: A Pilgrimage to the Dawn of Evolution

Alison Gopnik, professor of psychology at the University of California, Berkeley; her books include The Scientist in the Crib

Paul Steinhardt, theoretical physicist; Albert Einstein professor of science at Princeton University