The return to the biopsychosocial model of illness and health is the main motive of psychoso- matic thinking, which was formed at the turn of the 20th century in Europe. Various represen- tatives of psychoanalysis contributed to this process.
Sigmund Freud, Alfred Adler and Georg Groddeck, whose life and peculiar thinking are the main focus of this paper, were the most important contributors. The rejection of dualism of body and soul in the treatment of somatic and mental illnesses is Groddeck's main mission.
His fundamental concept is the mysterious "It", which unites both body and soul in one entity. Even Freud was fond of him, on top of that he adopted, revised and incorporated Groddeck's fundamental concept into the structural mo- del of the mind.
However, with his relentless struggle for psychosomatic unity and the use of psychoanalysis in the treatment of somatic diseases, Groddeck loses Freud's favor and his work falls into oblivion. It was in the second half of the 20th century when Groddeck was rediscove- red in Germany and later on valued as the key thinker for the formation of psychosomatic me- dicine.
This paper presents Groddeck's life and his thinking and evaluates his influence on well- known representatives of the psychoanalytic movement in the first half of the 20th century and his impact on today's psychosomatic thinking.