Pauli makes a short remark on the application of quantum-mechanical formalism to classical theories.

Pauli thanks for a paper sent in honour of Bohr's 60th birthday. He cannot accept Dirac's theory from the standpoint of physics because it leads to results contradicting the required correspondence to the classical theory.

Pauli expresses his dissatisfaction over Dorac's remarks in the Proc. R. S. on Heisenberg's and pauli's papers on quantum electrodynamics. He particularly argues against Dirac's doubts as to the relativistic and the invariance of quan tum electrodynamics.

Pauli thanks Dirac for his readiness to help Pauli's jewish cousin in getting a British visa.

Pauli gives further details concerning his jewish cousin.

Pauli's letter concerns his paper with Fierz on particles with arbitrary spin. He asks Dirac to communicate it to the Royal Society. the paper shows that a consistent theory of such particles in an electromagnetic field is possible.

Pauli's letter deals with Dirac's new formulation of quantum electrodynamics. He objects to the fact that Einstein's radiation laws are not derived but introduced as additional assumptions and refers to

Pauli makes some new remarks on Dirac's theory on the occasion of sending him a copy of Pauli's paper on Dirac's method of field-quantization.

Pauli expresses his interest in some results of Dirac's pupil Eliezer and he makes some critical comments on his paper.

After receiving another letter by Eliezer, Pauli is satisfied that Dirac's "hypothetical world" is mathematically self-consistent, but its physical meaning, i.e. its commection with the actual world,