What causes addiction? Johann Hari, author of Chasing the Scream, travelled some 30,000 miles in search of an answer. He met with researchers and lawmakers, drug dealers and drug makers, those who were struggling with substance abuse and those who had recovered from it, and he came to the conclusion that our whole narrative about addiction is broken.  "The opposite of addiction is not sobriety," he argues. "The opposite of addiction is connection." But first, we have to figure out what it really means to connect.