You don't believe in organized religion, yet a major theme in so many of your works seems to be a quest for God.

Deep beneath the surface of the Sun, enormous forces were gathering. At any moment, the energies of a million hydrogen bombs might burst forth in the awesome explosion.... Climbing at millions of miles per hour, an invisible fireball many times the size of Earth would leap from the Sun and head out across space.

I'm sure we would not have had men on the Moon if it had not been for Wells and Verne and the people who write about this and made people think about it. I'm rather proud of the fact that I know several astronauts who became astronauts through reading my books.

A wise man once said that all human activity is a form of play. And the highest form of play is the search for Truth, Beauty and Love. What more is needed? Should there be a ‘meaning’ as well, that will be a bonus? If we waste time looking for life’s meaning, we may have no time to live — or to play.

Open the pod bay doors, Hal.

Sometimes a decision has to be made by a single individual, who has the authority to enforce it. That's why you need a captain. You can't run a ship by a committee-at least not all the time.

Now, before you make a movie, you have to have a script, and before you have a script, you have to have a story; though some avant-garde directors have tried to dispense with the latter item, you'll find their work only at art theaters.