Pauli comments on Heisenberg's letter and his introduction of the square of fluctuation in zero approximation.

Pauli indicates a weakness in Dirac's theory.

Pauli replies to Heisenberg's letter of the 1st February.

Pauli writes about Uhlenbeck's appointment in Utrecht. Pauli is glad that Kronig has written to him, in spite of Pauli's remark regarding the spin problem (in Tübingen). Pauli makes some remarks about him and Uhlenbeck. He thinks that Kronig should go to America, in spite of his doubts. He makes remarks on Jordan's and de Broglie's paper on the neutrino.

Pauli has received from Rosental a copy of Bohr's article for "Dialectica" and Bohr's letter. This article will be of great help to him to clarify the contents of other articles in the issue, particularly Bohr's definition of "phenomenon". It would be a great help for the general editorial comment on the whole issue, if Bohr could return to Pauli the proofs of Einstein's article and also drop him a line on his opinion about the remarks which Pauli made himself in his letter to Einstein (of which Bohr has a copy). Every criticism is welcome.

Pauli makes further remarks about the H-theorem.

Pauli writes more about form-factors. The analogon of the arbitrary cut between observed system and means of observation in field theory has yet to be found. Pauli thinks of some group-theoretical formulation by which the same physical object is either seen as source of the field or as produced field. He talks on ideas about the origin of life and its connection with the realization of low probabilities.

Pauli replies to Göhring's letter of the 6 May 1954. He suggests "Science and Western Thought" as title for his lecture. He explains his meaning of "western".

Pauli writes about the topic of his lecture to be given in Lund. He makes some remarks about scientists mixing in politics because he is against it.

Pauli sends Bohr a copy of his article for the Sommerfeld-Festschrift with a few comments. He writes about Kronig's work on band-spectra. He also talks about his good cooperation with Scherrer and about his plans for the vacation.