Pauli offers detailed comments on Jauch's calculations.

Pauli expresses his interest in the work of Hu and Lopes and gives advice on how to treat the problem in the case that a strict solution of the equations should be impossible. He comments on offprints he got from Switzerland.

Pauli comments on Jauch's calculations and gives advice as to the preferable alternatives. He thinks that Jauch's method is important and urges him not to give it up in spite of Jauch's doubts.

Pauli expresses his doubts about Lopes last results, because of the inconsistency of the pertubation method used by him. He mentions similar difficulties in previous work by other authors.

Pauli is glad that the difficulties in Lopes' work have been overcome. He adds some more remarks about the regularity of integral operators.

Pauli comments on calculations made by Jauch. He writes of a letter from Bhabha (Bangalore) about the spin of the mesons. He comments on rumours about Heisenberg's idea of a fundamental length. Pauli is sceptical because he sees no connection with the atomicity of the electric charge.

Pauli discusses the problem of the singularity of the V-operator. His criticism applies also to the case of strong coupling in pair-theory.