When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong. Perhaps the adjective 'elderly' requires definition. In physics, mathematics, and astronautics it means over thirty; in the other disciplines, senile decay is sometimes postponed to the forties. There are, of course, glorious exceptions; but as every researcher just out of college knows, scientists of over fifty are good for nothing but board meetings, and should at all costs be kept out of the laboratory!

Science can destroy religion by ignoring it as well as by disproving its tenets. No one ever demonstrated, so far as I am aware, the nonexistence of Zeus or Thor, but they have few followers now.

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.

The difference between machines and human beings is that human beings can be reproduced by unskilled labour.

Now times had changed, and the inherited wisdom of the past had become folly.

If man survives for as long as the least successful of the dinosaurs-those creatures whom we often deride as nature's failures-then we may be certain of this: for all but a vanishingly brief instant near the dawn of history, the word 'ship' will mean- 'spaceship.'

If man can live in Manhattan, he can live anywhere.