When you look more generally at life on Earth, you find that it is all the same kind of life. There are not many different kinds; there's only one kind. It uses about fifty fundamental biological building blocks, organic molecules.

The immense distances to the stars and the galaxies mean that we see everything ins pace int he past, some as they were before the Earth came to be. Telescopes are time machines.

For all its material advantages, the sedentary life has left us edgy, unfulfilled, even after 400 generations in villages and cities, we haven't forgotten: The open road still softly calls like a nearly forgotten song of childhood.

That kind of skeptical, questioning, "don't accept what authority tells you" attitude of science - is also nearly identical to the attitude of mind necessary for a functioning democracy. Science and democracy have very consonant values and approaches, and I don't think you can have one without the other.

The fact that someone says something doesn't mean it's true. Doesn't mean they're lying, but it doesn't mean it's true.

If our long-term survival is at stake, we have a basic responsibility to our species to venture to other worlds. Sailors on a becalmed sea, we sense the stirring of a breeze.

The suppression of uncomfortable ideas may be common in religion or in politics, but it is not the path to knowledge; it has no in the endeavor of science. We do not know in advance who will discover fundamental insights.