This book is about the brain, but I will not say much about neurons, hormones, and neurotransmitters. That is because the mind is not the brain but what the brain does, and not even everything it does, such as metabolizing fat and giving off heat. The 1990s have been named the Decade of the Brain, but there will never be a Decade of the Pancreas. The brain’s special status comes from a special thing the brain does, which makes us see, think, feel, choose, and act. That special thing is information processing, or computation.