"Thinking very hard about the same problem for several hours can produce a severe fatigue, close to a breakdown. I nev…"

"For many years I was the youngest among my mathematical friends. It makes me melancholy to realize that I now have be…"

"Ada came from Lwów. She was a very good looking girl who was studying mathematics at the University of Geneva. For a …"

"It was not so much that I was doing mathematics, but rather that mathematics had taken possession of me."

"It is most important in creative science not to give up. If you are an optimist you will be willing to "try" more tha…"

"The mathematicians know a great deal about very little and the physicists very little about a great deal."

"Whatever is worth saying, can be stated in fifty words or less."

"The first sign of senility is that a man forgets his theorems, the second sign is that he forgets to zip up, the thir…"

"I'm an agnostic. Sometimes I muse deeply on the forces that are for me invisible. When I am almost close to the idea …"

"I thought that the description of Don Quixote's fight with the windmills the funniest thing imaginable."