Pauli replies to Heisenberg's letter of the 30 October, on $\gamma$-invariance and conservation of electric charge: which group corresponds to this? He talks about mirror-invariance in isotopic spin space.

Pauli replies to Heisenberg's letter of the 16 December and discusses the formalism and correction of a mistake Pauli made. He writes on group theoretical considerations.

This is the continuation of the letter of the 16 January 1958. Pauli gives a new idea of indefinite metric.

Pauli continues his last letter.

Pauli gives some more suggestions for formulation of their results.

Pauli writes to Heisenberg about a letter from Laue who thinks that at the "memorial meeting" for Planck one should talk about Planck and not about one's own work.

Pauli writes to Heisenberg of his decision to withdraw from the publication of the pre print, as no longer agrees with essential parts of its contents.

Pauli writes of his definite decision not to publish together with Heisenberg paper "On the isospin group in the theory of elementary particles", because essential parts of the pre print cannot be backed by him. He says that free to publish the paper alone. He summarizes his own views: 1)out of the degeneracy of the vacuum the possibility of a half-integer difference between ordinary spin and isospin cannot be concluded. 2)The idea of unification of field for strange particles has failed. 3)The eigenvalue problem has not been solved. 4)The physical meaning of the indefinite metric has not been clarified.

Pauli acknowledges receipt of Heisenberg's manuscript and makes a few comments.

Pauli writes a letter of condolence to Mrs Hecke some time after the death of E Hecke in 1947 tracing some of Hecke's characteristic attitudes in life.