"I would like to add a third possibility, that it might be that, when we die, we just die, and that's the end of it."

"I'm not a serious fellow."

"The highest forms of understanding we can achieve are laughter and human compassion."

"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…"

"I would often go to these conferences where they would talk about the ultimate theory, and I would always say, 'What's the ultimate experiment?'"