Close your eyes and touch your nose. You can do it because of proprioception—the body's internal sense of position. But at age 19, Ian Waterman lost this sense completely due to a rare viral infection. He became a "rag doll," unable to stand, sit, or even hold a cup, despite having healthy muscles. He had lost his body. In the tradition of Oliver Sacks, this book tells the inspiring story of how Ian taught himself to move again by using his eyes to replace his nerves. He has to consciously watch every limb to move it. It is a profound exploration of the "sixth sense" that grounds us in reality, and what happens when the connection between mind and flesh is severed.