Kraepelin is the founder of modern scientific psychiatry, psychopharmacology and psychiatric genetics, according to [[the eminent psychologist H. J. Eysenck]]. He postulated that psychiatric disorders are principally caused by biological and genetic disorders. His psychiatric theories dominated the field of psychiatry at the turn of the century. He vigorously opposed the approach of [[Freud]] who regarded and treated psychiatric disorders as caused by mysterious psychological forces. Though his contribution was largely ignored through most of the twentieth century in favor of an uncritical adoption of the Freudian etiological theories, Kraepelin's basic concepts now dominate research and academic psychiatry, and today the published literature in the field of psychiatry is overwhelmingly biological and genetic in its orientation. Largely for political reasons, Kraepelin's great contribution in discovering schizophrenia and manic-depression remains relatively unknown to the general public and his work is little read, despite the widespread adoption of his fundamental theories on the etiology and diagnosis of psychiatric disorders.
