[On President Bush's plan to get to Mars in 10 years] Stupid. Robots would do a better job and be much cheaper because you don't have to bring them back.

You cannot understand the glories of the universe without believing there is some Supreme Power behind it.

I believe in the possible. I believe, small though we are, insignificant though we may be, we can reach a full understanding of the universe. You were right when you said you felt small, looking up at all that up there. We are very, very small, but we are profoundly capable of very, very big things.

It is said that there's no such thing as a free lunch. But the universe is the ultimate free lunch.

Save water. Shower with your girlfriend.

We only have to look at ourselves to see how intelligent life might develop into something we wouldn't want to meet.

I think computer viruses should count as life.