Robert Wright, an award-winning author and journalist, writes for such magazines as The New Republic, The Atlantic, and The New Yorker. His new book, "Nonzero: The Logic of Human Destiny," examines biological and cultural evolution for evidence of higher purpose. His most recent book, "The Moral Animal: Evolutionary Psychology and Everyday Life," has been published in nine languages and was named one of the 12 best books of 1994 by The New York Times Book Review.