Scientific knowledge is a body of statements of varying degrees of certainty -- some most unsure, some nearly sure, none absolutely certain.

If I could explain it to the average person, I wouldn't have been worth the Nobel Prize.

When you're thinking about something that you don't understand, you have a terrible, uncomfortable feeling called confusion... Now, is the confusion's because we're all some kind of apes that are kind of stupid working against this, trying to figure out [how] to put the two sticks together to reach the banana and we can't quite make it... So I always feel stupid. Once in a while, though, the sticks go together on me and I reach the banana.

To test whether you have learned an idea or a definition, rephrase what you just learned without using the new word.

Nature does not care what we call it, she just keeps on doing it.

The basis of action on love, the brotherhood of all men, the value of the individual... the humility of the spirit.

Start out understanding religion by saying everything is possibly wrong... As soon as you do that, you start sliding down an edge which is hard to recover from.