but has for many years impeded the appreciation and acceptance of an "organic basis" of mental disease. The major obstacle was the emergence of psychoanalysis as a self-contained intellectual system instead of as a companion of the "organic approach". Once the basic ideas had been accepted, psychoanalysis appeared to offer the psychiatrist and medical scientist an integrated interpretation of normal and abnormal functioning of the brain. It should be mentioned that thc "organic approach" does not hold out hope for an early understanding of organically anchored psychodynamics. Neurochemistry, in relation to function, will become increasingly productive after the functional correlatives of cerebral metabolism have been found in behavioral phenomena. This study is in its infancy and the underlying ideas are at present no more than working hypotheses, but they represent a new approach to problems of the function of the central nervous system in health and disease. During the last few years support for this approach has gained ground. Before that, the probable hereditary basis of schizophrenia appeared to many psychiatrists as the only indication of an organic basis of mental disease, although it did not seriously shake their belief in the environmental origin of the major psychoses.