Today's guest is Jonathan Haidt, whose new book is The Anxious Generation: How the Great Rewiring of Childhood Is Causing an Epidemic of Mental Illness. The New York University psychologist and Heterodox Academy cofounder argues that what he calls a play-based childhood has been replaced with a phone-based one over the past 50 years, leading to skyrocketing rates of depression, anxiety, and suicide among younger Americans.