Pauli makes a short remark on the H-theorem.

Pauli replies to Heisenberg's letter of 27 February. He thinks that understanding between him and Heisenberg may be impossible, because he regards Heisenberg's calculations and interpretation as "wishful thinking". There is a discussion of the parity problem.

Pauli makes remarks about a paper by Lüders on the TCP-theorem and about the formulation of the parity condition.

Pauli reports on Jost's results concerning the TCP-theorem.

Pauli replies to Lüders' comments on Pauli's last paper.

Pauli writes about a problem which has still to be solved: the application of the theory of invariants to the decay of My-mesons. He writes of his discussions with Heisenberg on a special case of the Lee-model.

Pauli sends a circular letter concerning Heisenberg's paper on isospin. He explains why he withdrew his participation in Heisenberg's publication.

Pauli thanks Elsasser for his book "The Physical Foundation of Biology" and he discusses a few of its topics.

Pauli mentions his recent experiments in Heidelberg von Stek about polarization of Beta-electrons of RaE.