[Nosology of schizophrenia (author's transl)].

Schizophrenia and its variations, the different concepts and criteria for the diagnosis of schizophrenia and the possibilities of "prognostic diagnosis" at the beginning of the disease are discussed. There is only a differential typology between schizophrenia and cyclothymia and no sharp differential diagnosis. The numerous attempts to separate the two large groups of disease types are critically reported. Uncharacteristically pure residual states which leave the center of personality intact are more frequent than typical schizophrenic personality changes; the majority of schizophrenic patients are socially cured after more than two decades. More recent investigations on the course lead to an approximation to the concept of the "homogenous psychosis" and compel a greater observation of the "stratification rule" in the diagnosis.