Pauli and nuclear spin

There seems to be an increasing interest in the history of physics, especially of the physics of the roaring twenties when modern atomic structure and quantum mechanics were born. Writing about so recent a period, with most of the participants still alive, can lead to numerous unpleasant disagreements. It would be most valuable if the principal actors would each tell their own story, just as generals are now writing about their own world war. It must be understood that such stories relate only subjective experiences mixed with uncertain inferences. These accounts can be extremely interesting, but they should not be considered as an objective history of the new physics and should be written in the first person singular. An objective history of science is perhaps only possible in very broad outlines and in its relation to the rest of history. When we try to look at a recent event with a microscope, the resolving power may often be insufficient. We would like to see clearly the lines of thought followed by the participants, but even they themselves may not be aware of why and how they arrived at their important results, and they may tell us instead what are merely rationalizations after the fact. It is rather easy to construct a history which gives a very plausible account of how new ideas and experiments could or should have developed, but it seems impossible to know how they actually arose, particularly when we ask about details.