What, if anything, do dreams tell us about ourselves? What is the relationship between types of sleep and types of dreams? Does dreaming serve any purpose? Or are dreams simply meaningless mental noise—"unmusical fingers wandering over the piano keys"?

With expertise in philosophy, psychology, and neuroscience, Owen Flanagan is uniquely qualified to answer these questions. In this groundbreaking work, he provides both an accessible survey of the latest research on sleep and dreams and a compelling new theory about the nature and function of dreaming. Flanagan argues that while sleep has a clear biological function and adaptive value, dreams are merely side effects, "free riders," irrelevant from an evolutionary point of view. But dreams are hardly unimportant. Flanagan argues that dreams are self-expressive, the result of our need to find or to create meaning, even when we're sleeping. Written with remarkable insight, Dreaming Souls offers a fascinating new way of apprehending one of the oldest mysteries of mental life.