Michael McCullough is a professor of psychology at University of California, San Diego, where he runs the Evolution and Human Behavior Lab. Mike and I had a chat about his new book, "The Kindness of Strangers." The title for that book as originally conceived was "Why We Give a Damn" -- and even prior to that "Why We Don't Give a Damn." I happen to like those titles, though I can understand why the publisher didn't, and so I thought I'd trot them out to have a modest life of their own. In this conversation, we talk about Mike's first inspiration to study psychology, the influence of Christianity on his personal development and later his study of religion, his approach to mentorship, where he thought the conversation surrounding the biological basis of altruism went wrong, and rethinking the parable of the Good Samaritan.