Greg Epstein is the Humanist Chaplain at Harvard University and the president of the Harvard Chaplains. He is the author of the New York Times bestselling book, Good Without God: What a Billion Nonreligious People Do Believe.
Yo-Yo Ma is widely considered one of the greatest living musicians. A graduate of Harvard College, he has been awarded the Glenn Gould Prize, the National Medal of Arts, the Presidential Medal of Freedom, and the Polar Music Prize. He has won over a dozen Emmy awards.