A good engineer gets stale very fast if he doesn't keep his hands dirty.

Nature does not know extinction; all it knows is transformation. ... Everything science has taught me-and continues to teach me-strengthens my belief in the continuity of our spiritual existence after death. Nothing disappears without a trace.

All one can really leave one's children is what's inside their heads. Education, in other words, and not earthly possessions, is the ultimate legacy, the only thing that cannot be taken away.

Crash programs fail because they are based on theory that, with nine women pregnant, you can get a baby in a month.

Basic research is what I am doing when I don't know what I am doing.

There are flying grandfathers. But I intend to be an orbiting grandfather.

I'm convinced that before the year 2000 is over, the first child will have been born on the moon.