As a term of diagnosis "insanity" has become almost as meaningless as "paralysis," "apoplexy," "chorea" and "water on the brain." Even "mania," "melancholia," "paranoia" and "dementia" are fast losing their scientific significance, if indeed they ever had any. The word "psychosis," borrowed from psychology and applied scientifically, in modern psychiatry, to all states of unwonted mentalization, is coming more and more to stand for a particular class of phenomena, namely, individual psychophysiologic reaction to environment.
In consonance with the newer teachings of psychology it is beginning to be recognized that there are no mental diseases in the old sense, capable of classification as distinct and separate entities, but that there are merely broad and general groups of symptoms and strange mental exhibitions, each group indicating in a gross way the individual's bias or personal idiosyncrasy. Personality is a functional synthesis evolved under the influence of heredity and environment, a fact