Jacques Solomon (1908-1942) was a theoretical physicist whose career was short and hectic. He was Paul Langevin’s son-in-law and took part with him in the sudden surge of rationalism during the 30s. He was a Marxist activist, interested in dialectical materialism and its application in scientific research. He took part in the debate over the interpretation of quantum mechanics, whose assimilation in France was slow and difficult. He was trained at the Copenhagen school, but was nevertheless an uncompromising materialist who tried to conciliate several schools of thought, in order to give an answer to the difficult problem of indeterminism