Sam Harris speaks with Jared Diamond about the rise and fall of civilizations. They discuss political polarization, disparities in civilizational progress, the prospect that there may be biological differences between populations, the precariousness of democracy in the US, the lack of a strong political center, immigration policy, and other topics. Jared Diamond is Professor of Geography at the University of California, Los Angeles. Among his many awards are the U.S. National Medal of Science, Japan’s Cosmos Prize, a MacArthur Foundation Fellowship, a Pulitzer Prize for General Nonfiction, and election to the U.S. National Academy of Sciences. He is the author of the international best-selling books Guns, Germs, and Steel; Collapse; Why Is Sex Fun?; The World until Yesterday, and The Third Chimpanzee. He is also the presenter of a TV documentary series based on three of those books. His newest book is Upheaval: Turning Points for Nations in Crisis. Website: jareddiamond.org