Steven D. Levitt, a professor of economics at the University of Chicago, was awarded the John Bates Clark medal, given to the most influential American economist under the age of forty. He is also a founder of The Greatest Good, which applies Freakonomics-style thinking to business and philanthropy. Stephen J. Dubner is an award-winning author, journalist, and radio and TV personality. He quit his first career-as an almost-rock-star-to become a writer. He has worked for The New York Times and published three non-Freakonomics books. He lives with his family in New York City.