This is a book written with a depth of literature review that should appeal to neurologists interested in the application of basic science to their profession. In addition, the text tries for a clarity that should invite a look by educated non-scientists. To reverse engineer brain arousal mechanisms, I reframe a vital question with a formulation not previously used: “Why does any animal or human do anything at all”? Beyond citing facts, I propose theoretical ideas about how brain arousal systems are organized. They must be reliable and they are. First, the nerve...