To obtain a mental picture of the distance to the nearest star, compared to the nearest planet, you must imagine a world in which the closest object … - Arthur C. Clarke

One of the biggest roles of science fiction is to prepare people to accept the future without pain and to encourage a flexibility of mind. Politicians should read science fiction, not westerns and detective stories. Two-thirds of 2001 is realistic — hardware and technology — to establish background for the metaphysical, philosophical, and religious meanings later.

"Any sufficiently advanced technology is indistinguishable from magic."

"Two possibilities exist: Either we are alone in the Universe or we are not. Both are equally terrifying."

. . . 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.