I learned very early the difference between knowing the name of something and knowing something.

Religion is a culture of faith; science is a culture of doubt.

If you thought that science was certain - well, that is just an error on your part.

You can know the name of a bird in all the languages of the world, but when you're finished, you'll know absolutely nothing whatever about the bird... So let's look at the bird and see what it's doing -- that's what counts.

Physics is like sex: sure, it may give some practical results, but that's not why we do it.

What I am going to tell you about is what we teach our physics students in the third or fourth year of graduate school... It is my task to convince you not to turn away because you don't understand it. You see my physics students don't understand it... That is because I don't understand it. Nobody does.