We batter this planet as if we had someplace else to go.

The Universe revealed by science is one of far more awesome grandeur than any religion has ever posited.

This planet seems to be in such sorry shape. And I can't ever think about the rest of the universe without coming back home and thinking what the implications for life here would be if we were to really have some definitive proof of extraterrestrial life.

If you have a beating heart, that's good enough.

Ten long trips around the sun since I last saw that smile, but only joy and thankfulness that on a tiny world in the vastness, for a couple of moments in the immensity of time, we were one.

If you are searching for sacred knowledge and not just a palliative for your fears, then you will train yourself to be a good skeptic.

I remember that one time Carl Sagan was giving a talk, and he spelled out, in a kind of withering succession, these great theories of demotion that science has dealt us, all of the ways in which science is telling us we are not who we would like to believe we are. At the end of it, a young man came up to him and he said: "What do you give us in return? Now that you've taken everything from us? What meaning is left, if everything that I've been taught since I was a child turns out to be untrue?" Carl looked at him and said, Do something meaningful.