But take another set of individuals, a more distant tribe, and among these the brains differ from those of the first set in some chemically and physiologically significant way. These are the mentally ill. The mad, the crazy: people who are schizophrenic, obsessive, paranoid, compulsive, sociopathic, bipolar, depressed, or some grim combination of two or more of these: these people all belong together, they ought to be classed with each other. Or so we think—and this is the rationale for the medical practice of psychiatry.
