In this startling study of human emotion, Dacher Keltner investigates an unanswered question of human evolution: If humans are hardwired to lead lives that are “nasty, brutish, and short,” why have we evolved with positive emotions like gratitude, amusement, awe, and compassion that promote ethical action and cooperative societies? Illustrated with more than fifty photographs of human emotions, takes us on a journey through scientific discovery, personal narrative, and Eastern philosophy. Positive emotions, Keltner finds, lie at the core of human nature and shape our everyday behavior—and they just may be the key to understanding how we can live our lives better.