Sam Harris speaks with A.J. Jacobs about religion, gossip, polyamory, health advice, our past and future selves, “radical honesty,” human genealogy, tribalism, and other topics.

A.J. Jacobs is the author of the New York Times bestsellers The Know-It-All, The Year of Living Biblically, and The Guinea Pig Diaries. He is the editor at large of Esquire magazine, a contributor to NPR, and has written for The New York Times, The Washington Post, and Entertainment Weekly. His most recent book is It’s All Relative: Adventures Up and Down the World’s Family Tree. He lives in New York City with his wife and kids. Visit him at AJJacobs.com.