If an elderly but distinguished scientist says that something is possible, he is almost certainly right; but if he says that it is impossible, he is very probably wrong.

There's a passage about 'rivers of molten rock that wound their way... until they cooled and lay like twisted dragon-shapes vomited from the tormented earth.' That's a perfect description: how did Tolkien know, a quarter century before anyone ever saw a picture of Io? Talk about Nature imitating Art.

At the present rate of progress, it is almost impossible to imagine any technical feat that cannot be achieved - if it can be achieved at all - within the next few hundred years.

I also believe - and hope - that politics and economics will cease to be as important in the future as they have been in the past; the time will come when most of our present controversies on these matters will seem as trivial, or as meaningless, as the theological debates in which the keenest minds of the Middle Ages dissipated their energies. Politics and economics are concerned with power and wealth, neither of which should be the primary, still less the exclusive, concern of full-grown men.

In this single galaxy of ours there are eighty-seven thousand million suns. [...] In challenging it, you would be like ants attempting to label and classify all the grains of sand in all the deserts of the world. [...] It is a bitter thought, but you must face it. The planets you may one day possess. But the stars are not for man.

Using material ferried up by rockets, it would be possible to construct a "space station" in ... orbit. The station could be provided with living quarters, laboratories and everything needed for the comfort of its crew, who would be relieved and provisioned by a regular rocket service. (1945)

Across the gulf of centuries, the blind smile of Homer is turned upon our age. Along the echoing corridors of time, the roar of the rockets merges now with the creak of the wind-taut rigging. For somewhere in the world today, still unconscious of his destiny, walks the boy who will be the first Odysseus of the Age of Space.