If you were to lose the tip of your little finger in an accident, you’d be saddened, but your conscious experience would be no different. By contrast, if you were to damage an equivalently sized piece of brain tissue, this can change your capacity to understand music, name animals, see colors, judge risk, make decisions, send signals to your muscles, use verbs or perform any of the other hidden, daily feats that we pull off seemingly without effort.
Thousands of natural experiments with brain tumors, degenerative disorders, genetic mutations, drug addictions and traumatic brain injury have taught a simple lesson: our hopes, ideas, desires and behaviors depend directly on the state of the enigmatic lump of thinking stuff.
