Kraepelinian dichotomy

The Kraepelinian dichotomy is the division of the major endogenous psychoses into the disease concepts of dementia praecox, which was reformulated as schizophrenia by Eugen Bleuler by 1908,[1][2] and manic-depressive psychosis, which has now been reconceived as bipolar disorder.

[3] It has been highly influential on modern psychiatric classification systems, the DSM and ICD, and is reflected in the taxonomic separation of schizophrenia from affective psychosis.

[6] In this text he reviewed the then heterogeneous state of medical taxonomies of mental illness and enumerated the existence of some thirty such nosologies from the early seventeenth-century until the mid-nineteenth-century.

[7] The major contribution of his published dissertation, which is still the foundation of modern psychiatric nosology,[7] was to first formulate the clinical method for the classification of psychosis by symptom, course and outcome.

[7] Emil Kraepelin first introduced his proposed dichotomy between the endogenous psychoses of manic-depressive illness and dementia praecox during a public lecture in Heidelberg, Germany on 27 November 1898.

Emil Kraepelin (1856–1926)