. . . Moon-Watcher felt the first faint twinges of a new and potent emotion. It was a vague and diffuse sense of envy--of dissatisfaction with his life. He had no idea of its cause, still less of its cure; but discontent had come into his soul, and he had taken one small step toward humanity.

Mars is the next frontier, what the Wild West was, what America was 500 years ago. It's time to strike out anew....Mars is where the action is for the next thousand years....The characteristic of human nature, and perhaps our simian branch of the family, is curiosity and exploration. When we stop doing that, we won't be humans anymore. I've seen far more in my lifetime than I ever dreamed. Many of our problems on Earth can only be solved by space technology....The next step is in space. It's inevitable.

As three laws were good enough for Newton, I have modestly decided to stop there.

If I didn't exist, I would have invented myself.

Even if we never reach the stars by our own efforts, in the millions of years that lie ahead it is almost certain that the stars will come to us. Isolationism is neither a practical policy on the national or cosmic scale. And when the first contact with the outer universe is made, one would like to think that Mankind played an active and not merely a passive role-that we were the discoverers, not the discovered.

When the Sun shrinks to a dull red dwarf, it will not be dying. It will just be starting to live and everything that has gone before will merely be a prelude to its real history.

That's one of those meaningless and unanswerable questions the mind keeps returning to endlessly, like the tongue exploring a broken tooth.