Jordan replies to Pauli's questions as regards Jordan's cosmology with a changing gravitational constant. He believes that it is difficult to separate macro-physical and micro-physical considerations in his theory.

Jordan replies to Pauli's two letters. He agrees about the necessity for clarification of the physical significance of his formulae but he has some reservations as regards Pauli's criticism.

Jordan replies to a letter by Pauli. He discusses the problem of probability of mutations and of the statistical independence of successive mutations and the necessity for distinguishing between micro- and macro-evolution. He agrees with Pauli that nothing can be said at present about the time scale of evolutionary processes.

Jordan writes about a forthcoming talk by Pauli in Hamburg.

Jordan replies to Pauli's letter of the 1 October 1952 about the relation of Jordan's "projective" cosmology to that of Kaluza. He writes about possible empirical confirmations of the hypothesis of a changing gravitational constant.