Stephen Cole Kleene

I had some hesitations about philosophy because, if you worked out a philosophical theory, it was hard to know whether you were going to be able to prove it or whether other theories had just as good a claim on belief.

I am so tired of ruggedly handsome heroes. I don't know too many ruggedly handsome people who are necessarily nice people. In fact, the beautiful people have a big handicap because they rely too much on their appearance and don't bother to become interesting.

To those who ask what the infinitely small quantity in mathematics is, we answer that it is actually zero. Hence there are not so many mysteries hidden in this concept as they are usually believed to be.