Broad–narrow–broad: the circuitry of certainties and uncertainties

In the centuries between the great Greek founders of medicine and psychiatry, Hippocrates, Aretaeus of Cappadocia, Galenos of Pergamon or Soranos of Ephesos (see Longrigg, 1993; Marneros and Angst, 2000; Angst and Marneros, 2001) and the father of the modern psychiatric systematics, Emil Kraepelin, at the end of the nineteenth and the beginning of the twentieth century, physicians and psychiatrists described and allocated mental disorders according to broad criteria. Symptoms, which today in modern nomenclature are called “schizophrenic,” “affective,” “mood congruent” or “mood-incongruent,” were described as characteristics of the same disorder. Therefore, case reports published during this long historic period of more than 2400 years could, with the same strong arguments, be interpreted by modern psychiatrics as “pure schizophrenia,” or “pure affective disorder” or “typical schizoaffective.” At the end of the nineteenth century, Emil Kraepelin tried to clean the field, dichotomizing the so-called functional psychotic disorders into dementia praecox and manic-depressive illness (Kraepelin, 1896; 1899). The Kraepelinian dichotomy, which really was not very dichotomous, as Emil Kraepelin himself pointed out in 1920, received an epigonal strength by Kurt Schneider (1959) through the definition of “first-rank schizophrenic symptoms”: their existence confirms the diagnosis “schizophrenia” (provided that organic causal conditions can be ruled out). Kurt Schneider's ascetic strength completed in some way Karl Jaspers' hierarchical principle (1913).