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.

Pauli talks about the isotopic spin problem for charged particles.

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 reports from Milan that the paper could be published in 14 days in Nuovo Cimento. He has a few doubts about the latest test results.

Pauli acknowledges receipt of 10 copies of the pre print and letters of 13, 14 and 15 February. He finds that progress has been made, but is against early publication. He writes about a paper by Schiwinger where the mirror-particles have real existence. There are several points with which Pauli is not yet satisfied.