The presence of schizo-affective psychosis is postulated psychopathologically, if schizophrenic as well as manic or depressive cyclothymic symptoms, respectively, are to be found in the same clinical picture. This circumstance rises the question with what legitimation do we designate a symptom as schizophrenic, etc.? Generally, we call a symptom, e.g., schizophrenic, if: (1) like with K....