Wilhelm Fliess

Wilhelm Fliess (German: Fließ [fliːs]; 24 October 1858 – 13 October 1928) was a German otolaryngologist who practised in Berlin. He developed the pseudoscientific theory of human biorhythms and a possible nasogenital connection that have not been accepted by modern scientists. He is today best remembered for his close friendship and theoretical collaboration with Sigmund Freud, a controversial chapter in the history of psychoanalysis.