You either care or you don’t.

The most terrifying fact about the universe not that it is hostile but that it is indifferent

I, uh, don't think it's quite fair to condemn a whole program because of a single slip-up, sir.

If you can talk brilliantly about a problem

How could we possibly appreciate the Mona Lisa if Leonardo had written at the bottom of the canvas: 'The lady is smiling because she is hiding a secret from her lover.' This would shackle the viewer to reality, and I don't want this to happen to 2001.

Never say no to an idea - you never know how that idea will ignite another idea.

The hardest thing in making a movie is to keep in the front of your consciousness your original response to the material. Because that's going to be the thing that will make the movie. And the loss of that will break the movie.