Never judge your own writing. You're not fit to do so.

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

I even got a letter from a young woman in British Columbia that began as follows: 'Today I am eighteen. I am sitting at the window, looking out at the rain, and thinking how much I love you.'

If I had felt then as I feel now, or as I felt a few years after I had married her, nothing could possibly have persuaded me to marry a woman who smoked. Dates, yes. Sexual adventures, yes. But to pin myself permanently inside closed quarters with a smoker? Never. Never. Never. Beauty wouldn't count, sweetness wouldn't count, suitability in every other respect wouldn't count.

Science is a set of rules to keep us from telling lies to each other. All scientists really have is a reputation for telling the truth.

Happiness is doing it rotten your own way.

Science is uncertain. Theories are subject to revision; observations are open to a variety of interpretations, and scientists quarrel amongst themselves. This is disillusioning for those untrained in the scientific method, who thus turn to the rigid certainty of the Bible instead. There is something comfortable about a view that allows for no deviation and that spares you the painful necessity of having to think.