Steven Pinker: 'The Better Angels of our Nature: Why Violence Has Declined.'

Steven Pinker, author of "The Better Angels of our Nature: Why Violence Has Declined." He says we may be living in the most peaceful era in our species existence, and we should show gratitude for the institutions of civilization and enlightenment that have made it possible. Harvard University psychology professor Steven Pinker spoke in Minneapolis March 7, 2015 at the Nobel Peace Prize Forum sponsored by Augsburg College. The moderator was MPR's Tom Crann and St. Olaf College graduate Katie Lovrien introduced Steven Pinker.