Pauli invites Yang to a lecture in Zürich. He comments on an interpretation of a recent experiment by Garvin and Ledermann and by Deutsch and Frauenfelder on parity violation. He critizices two-component theory. He writes of his own views on T-invariance and conservation of Lepton-Charge. Only the development of quantized field theories will provide answers to the deeper questions.

This is a supplement to the letter of the 26th May 1957. Pauli comments on a theoretical paper by Preston (Birmingham) which fits well with Pauli's critical attitude towards the two-component theory. He writes about Preston's proposal to give up the conservation of leptons. Pauli thinks that T-invariance seems still to be possible.

Pauli comments on a paper by Salam and his B-field. He writes about the open question whether the rest mass of the B-particles is zero. He writes about the conservation of lepton charge, two-component theory and CP or T symmetry. He writes about Lüders' and Pauli's theorem, and Schwinger's previous theorem. He makes remarks on his calculations last autumn, connected with the "Pruett-factor".

Pauli writes about his impending trip to the USA. He writes about his work with Heisenberg.