David C. Krakauer is the President and William H. Miller Professor of Complex Systems at the Santa Fe Institute. An evolutionary biologist by training, he served as the founding director of the Wisconsin Institute for Discovery and currently co-directs the Collective Computation Group. John Lewis Gaddis is the Robert A. Lovett Professor of Military and Naval History at Yale University. He is the author of "The Cold War: A New History," "The Landscape of History," and "George F. Kennan: An American Life," which won the Pulitzer Prize. Kenneth Pomeranz is the University Professor of History at the University of Chicago and the author of "The Great Divergence: China, Europe, and the Making of the Modern World Economy." He is a former fellow of the Institute for Advanced Studies in Princeton and former president of the American Historical Association.