Pauli comments a letter from Fierz regarding the unitary representations of the Lorentz group.

Pauli makes some critical remarks on a letter by Fierz about the entropy change during a measurement. He adds a short reference to Bohr's view on this problem.

Pauli refers to some points for a future discussion with Fierz: 1) on the problem of divergencies in quantum electrodynamics 2) on the relation between concepts and sense perception. He also writes on the laws of nature as physical manifestation of archetypes and he refers to Kepler and his polemic with Fludd.

Pauli sends Fierz some critical remarks on an article written by Schrödinger who is not ready to accept the epistemological consequences of quantum mechanics. He also comments on Fierz's statement by an "arbitrary decision of the observer".

Pauli asks Fierz some personal questions regarding the chairs for theoretical physics in Zürich and Basel.

Pauli comments on an essay by Erich Neumann in the Eranos-Yearbook of 1948.

In this letter, Pauli gives further remarks on Weyl's parallel between Leibniz's principle and the exclusion principle. He also writes on Jung's synchronicity and its relation to causal events. It's said that the "elimination of all uncontrolable factors necessarily leads to destruction of the significance of synchronicity".

Pauli comments on a paper by Fierz. He makes comments on a book recommended to him by Fierz and he also writes on the imaginary antagonism between nations.

Pauli writes on the symbolic significance of trinity and quaternity, with reference to the polemic between Kepler and Fludd. He also writes on the problem of opposites: compensatory opposites and complementary opposites. He also develops the subject of the conceptual shortcoming of the field concepts.

Pauli writes on Schopenhauer's philosophy in the light of modern physics and psychology. For Pauli Eros and Logos are complementary opposites.