It is the tension between creativity and skepticism that has produced the stunning and unexpected findings of science.

Science is a way of thinking much more than it is a body of knowledge.

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.

Across the sea of space, the stars are other suns.

You mustn't think of the Universe as a wilderness. It hasn't been that for billions of years," he said. "Think of it more as... ..cultivated.

What is called for is an exquisite balance between two conflicting needs: the most skeptical scrutiny of all hypotheses that are served up to us and at the same time a great openness to new ideas. If you are only skeptical, then no new ideas make it through to you. On the other hand, if you are open to the point of gullibility and have not an ounce of skeptical sense in you, then you cannot distinguish useful ideas from the worthless ones.

By exploring other worlds we safeguard this one. By itself, I think this fact more than justifies the money our species has spent in sending ships to other worlds. It is our fate to live during one of the most perilous and, at the same time, one of the most hopeful chapters in human history.