You sell 2,000 pounds, you're going to make $700 while you're spending $250 to $300 every trip out. It's not worth it.

It [science fiction] really is the only genre that lets you use your imagination without limitations,

Put off your imagination, as you put off your overcoat, when you enter the laboratory. Put it on again, as you put on your overcoat, when you leave.

Science is vastly more stimulating to the imagination than are the classics.

Nature, to be commanded, must be obeyed. The imagination must be given not wings but weights.

Keats mourned that the rainbow, which as a boy had been for him a magic thing, had lost its glory because the physicists had found it resulted merely from the refraction of the sunlight by the raindrops. Yet knowledge of its causation could not spoil the rainbow for me. I am sure that it is not given to man to be omniscient. There will always be something left to know, something to excite the imagination of the poet and those attuned to the great world in which they live (p. 64)