Book excerpt: NATIONAL BESTSELLER • From “the poet laureate of medicine" (The New York Times) and the author of the classic The Man Who Mistook his Wife for a Hat comes a fascinating exploration of the remarkable, unpredictable ways that our brains cope with the loss of sight by finding rich new forms of perception. “Elaborate and gorgeously detailed.... Again and again, Sacks invites readers to imagine their way into minds unlike their own, encouraging a radical form of empathy.” —Los Angeles Times With compassion and insight, Dr. Oliver Sacks again illuminates the mysteries of the brain by introducing us to some remarkable characters, including Pat, who remains a vivacious communicator despite the stroke that deprives her of speech, and Howard, a novelist who loses the ability to read. Sacks investigates those who can see perfectly well but are unable to recognize faces, even those of their own children. He describes totally blind people who navigate by touch and smell; and others who, ironically, become hyper-visual. Finally, he recounts his own battle with an eye tumor and the strange visual symptoms it caused. As he has done in classics like The Man Who Mistook his Wife for a Hat and Awakenings, Dr. Sacks shows us that medicine is both an art and a science, and that our ability to imagine what it is to see with another person's mind is what makes us truly human.