" It is conceivable, of course, that significant physicochemical disturbances will be found in some “mental patients” and in some “conditions” now labeled “mental illnesses.” But this does not mean that all so-called mental diseases have biological “causes,” for the simple reason that it has become customary to use the term “mental illness” to stigmatize, and thus control, those persons whose behavior offends society—or the psychiatrist making the “diagnosis. "

― Thomas Szasz , The Myth of Mental Illness: Foundations of a Theory of Personal Conduct