D O C U M E N T 3 3 1 D E C E M B E R 1 9 2 8 3 1 7 331. From Pascual Jordan Hamburg 36, 11 December 1928 Dear Professor Einstein, Many hearty thanks for your detailed letter! I indeed knew that a priori statistics had always seemed rather uncanny to you, but it was new to me and very instruc- tive to hear your opinions in such a detailed and precise formulation. As for myself, I must certainly admit that I would not want to give up my belief in a priori statis- tics for which I will no doubt find, if not your physical approval, at least your hu- man understanding.[1] If I should indicate my opinion of the innermost sense of the matter, (then I would certainly not choose to say that God throws dice for the electrons [2] rather, I would say that: He allows the electrons to decide themselves in each case.) Thus, in my opinion, our dear God provides the electrons directly only with their created characteristics and from these, the statistical laws emerge precisely because each individual electron is completely free and independent of the others in making its decisions. This manner of imagining the situation would seem to be particularly manifest in regard to biological systems I believe that in organisms, genuinely lawful devi- ations from the inorganic processes of the physical reactions can occur, which one could roughly characterize in a quite primitive manner as that the atoms or elec- trons belonging to a living individual to a certain extent adjust their otherwise sta- tistically disordered decisions to each other.— As far as the fundamentals regarding the theory of knowledge are concerned, there I am indeed likewise inclined to be very radical and revolutionary. There seems to me to be no logical escape from considering—in a consistent application of Mach’s ideas—the totality of the immediately perceived and experienced as the actual, certain “reality,” and everything else as a symbolic construction that allows its logically simple description.[3] I have in fact thought more about these questions than about all of physics, and I believe that the well-known, apparent impossibili- ties of such a radical viewpoint will vanish of themselves through a truly consistent application.— I hope to come once to Berlin in February or March, and I look forward to being able to introduce myself personally to you on that occasion. With many friendly greetings, sincerely yours, P. Jordan