Fierz speculates about the roots of Jung's synchronicity. He agrees with Pauli about the connection with Leibniz's principle of sufficient reason, which cannot be reduced to logic, and his principle of contradiction which is a logical one. Both principles complement and exclude each other. There are possible relations between human consciousness and the idea of law.

Fierz elaborates on physical grounds, for proposed changes in their work, on the H-theorem. He focuses on entropy.

Fierz questions Szilard's assertion on reversibility of mixture of systems. He considers how measurement might be seen as turning pure state into a mixture.

Fierz sends a short addition to his letter of the 1st June 1954, fierz_0016-142r.

Fierz makes comments on a paper by Salam which was sent to Fierz by Pauli.

Fierz comments on van Hove's theory.

Fierz makes some critical remarks on a paper sent to him by Pauli written by Heisenberg, in particular on a discussion of the S-matrix.

Fierz replies to a question put by Pauli in his letter, about causality and quantum electrodynamics.

Fierz gives some additions to his previous letter and makes some connections with Kant's categories.

In this letter, Fierz makes a reference to a passage in Molière's "Les Femmes savantes".