Classification of Endogenous Psychoses and their Differentiated Etiology

Always using his own life-long case studies, Leonhard divided the endogenous psychoses into five main nosological groups: on the one hand, the prognostically favourable unipolar affective psychoses, bipolar affective psychoses and cycloid psychoses, and, on the other hand, the prognostically unfavourable unsystematic and systematic schizophrenia.