Pauli agrees to Bergmann's comments on Misner's argument concerning the vanishing of the Hamilton function.

Letter amplifying his cable from the boat to the USA, urging Heisenberg not to publish now and not to send anything off before giving Pauli an opportunity to express his view. He wants Heisenberg's clear reply on the degeneration of the vacuum, mirror states, the metric in Hilbert space and the eigenvalue problem. He gives more details about the last point. He writes about reactions of colleagues (also Bohr) in New York to their ideas. The scepticism of Yang and Lee and of Heisenberg's pupils, has made Pauli feel that publication should be deferred.

Pauli writes that the crucial question for the spinor model is whether a reasonable formulation of an eigenvalue problem can be found for the masses of the particles. He talks about a special question concerning interaction in quantum mechanics: do products of field operators for the same point have a well defined meaning? He does not accept Källén's arguments against the spinor model.

He agrees with Keller's paper on "Hidden variables" in quantum theory (P.R.89, 1040) as regards the role of probability in Bohm's interpretation and refers to his own paper in the anniversary volume (60th birthday) for L. the Broglie same subject.

Letter from Dover Publications (H. Cirker) to Pergamon Press (P. Rosbaud).

Letter from Dover Publications (H. Cirker) to W. Pauli. Related to the republication of "The theory of relativity".