What does drug withdrawal have in common with a broken heart? Why is the enemy of memory not time but other memories? How can a blind person learn to see with her tongue, or a deaf person learn to hear with his skin? Might we someday control a robot with our thoughts, just as we do our fingers and toes? Why do we dream at night, and what does that have to do with the rotation of the earth? The answers to these questions are right behind our eyes. The greatest technology we have ever discovered on our planet is the three-pound organ carried in the vault of the skull. The magic of the brain is not found in the parts it’s made of but in the way those parts unceasingly reweave themselves in an electric, living fabric.