Heredity and Constitution in Aetiology of Psychic Disorders

The significance of heredity and constitution in psychic diseases is not limited to those groups of mental disorders which, in the narrower sense, are usually termed " hereditary diseases," but reaches far beyond them.Con- versely, the diversity of causes in hereditary diseases is by no means exhausted by what we call heredity and con- stitution.The Three Main Groups of Psychoses Let us, to begin with, concentrate on these hereditary diseases in the narrower sense of the term-that is to say, mainly on the three main groups of the manic-depressive, the schizophrenic, and the epileptic diseases.If in these