On Writing a Book
If you are going to write a non-fiction book about some events in the past, you had better choose carefully a story that you are really interested in with characters that you want to get to know better because you are probably going to be spending a lot of time with them. It is likely to be at least two years and if you are not deeply interested in what they were doing and the times they were living in, you will not be able to convince anybody else to read the book you intend to write.
At best, the story has a curious way of telling itself, so there is a certain thrill in going to your word processor in the morning, collecting the facts and finding out what is going to happen next. My last book was about what a group of physicists said to another in the late 1920s and early 1930s. Since the letters of Bohr, Heisenberg, Pauli and others have been assembled and preserved, I often had the feeling of eavesdropping on their conversations with the bonus of knowing how it was all going to work out.
Another added benefit was that they were developing quantum mechanics, the most radical set of scientific ideas of the 20th century. I learned the subject in school, taught as if it had been handed down from on high inscribed on stone tablets so it was especially exciting to see these extraordinary individuals struggling to understand all the puzzles they were facing, while knowing that in the end, they were going to come out with something great.
On the other hand, I felt powerless to warn them that Hitler was about to take power and their lives would be shattered.