Pauli comments on Heisenberg's formulation of field quantization and some questions on specified points.

Pauli replies to Heisenberg's letter of 1st January. He is not convinced that dipole-"ghosts" cannot appear in Lee's model and gives some reasons for this.

Pauli makes a few more remarks on Heisenberg's manuscript.

Pauli replies to Heisenberg's letter of 17 June, on pedagogical questions and on questions of principle.

Pauli talks about some remarks by Källén on Heisenberg's manuscript.

Pauli replies to Heisenberg's letter of the 9 December. He writes on the question of "real" and "complex" ghosts.

Detailed exposition of his suggestion about vacuum-expectation values. This nearly concludes the subject "interpretation of isospin".

Pauli writes about the possible form of publication of a joint paper.

Pauli makes additional remarks on the proposed joint paper.

Pauli replies to Heisenberg's question in his letter of 5 October.