 Reichenbach continued to revise and elaborate his ideas about probability in a series of papers in the early  1930s[3]  until, in 1935, his The Theory of Probability provided a fuller statement of his developed view. Surprisingly, Reichenbach does not acknowledge help from Richard von Mises, his colleague in Berlin and Istanbul in the period and the mathematician whose views on the foundations of probability were closest to his own and are often discussed in the book. He does attribute part of the mathematical work in the book to Valentine Bargmann, who after finishing his doctorate in physics in Berlin fled to Switzerland in 1933 and later became an assistant to von Neumann and to Einstein at the Institute for Advanced Study, from where in the 1940s he also assisted Reichenbach’s work on quantum theory. 