The universe must be full of voices, calling from star to star in a myriad tongues. One day we shall join that cosmic conversation.

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.

There is the possibility that humankind can outgrow its infantile tendencies, as I suggested in 'Childhood's End.' But it is amazing how childishly gullible humans are.

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

The more wonderful the means of communication, the more trivial, tawdry, or depressing its contents seemed to be.

All explorers are seeking something they have lost. It is seldom that they find it, and more seldom still that the attainment brings them greater happiness than the quest.

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