ZIEHEN

ZIEHEN Theodor (Theodor Ziehen; born 1862), German psychiatrist and psychologist, who successively held the chair of psychiatry in Utrecht, Halle, and from 1904 in Berlin, author of a course in psychiatry, a textbook of physiological psychology, and a treatise on the theory of knowledge (1898). Highly educated, Z. in his philosophical outlook adhered to the empiriocritical wing of positivism, while in psychiatry he followed the symptomatic direction. As a psychiatrist, Z. was not very popular, although, holding the chair in Berlin and being editor of the journal 'Monatsschrift fur Psychiatrie und Neurologie', he had the opportunity to exert significant influence on the development of German psychiatry at the turn of the 19th and 20th centuries. Z. was one of the pioneers in the study of 'borderline states' and abnormal childhood. He created one of the first practical schemes for psychological research of mental development. From 1912, Ziehen abandoned psychiatry and began to lecture on philosophy.