Professor of Psychology; Director, Evolution and Human Behavior Laboratory, University of California, San Diego, whose research is concerned with the evolutionary and cognitive underpinnings of prosocial behaviors and moral sentiments such as forgiveness, revenge, gratitude, empathy, and trust; Author, The Kindness of Strangers: How a Selfish Ape Invented a New Moral Code (2020) and Beyond Revenge: The Evolution of the Forgiveness Instinct (2008); Co-Author, To Forgive is Human (2009) and The Psychology of Gratitude (2004)