I have never, in all my life, not for one moment, been tempted toward religion of any kind. The fact is that I feel no spiritual void. I have my philosophy of life, which does not include any aspect of the supernatural and which I find totally satisfying. I am, in short, a rationalist and believe only that which reason tells me is so.

There are no nations! There is only humanity. And if we don't come to understand that right soon, there will be no nations, because there will be no humanity.

Until I became a published writer, I remained completely ignorant of books on how to write and courses on the subject ... they would have spoiled my natural style; made me observe caution; would have hedged me with rules.

He had read much, if one considers his long life; but his contemplation was much more than his reading. He was wont to say that if he had read as much as other men he should have known no more than other men.

People who think they know everything are a great annoyance to those of us who do.

To test a perfect theory with imperfect instruments did not impress the Greek philosophers as a valid way to gain knowledge.

I don’t like anything that’s got to be. I want to know why.