“Some dangers are so spectacular and so much beyond normal experience that the mind refuses to accept them as real, and watches the approach of doom without any sense of apprehension. The man who looks at the onrushing tidal wave, the descending avalanche, or the spinning funnel of the tornado, yet makes no attempt to flee, is not necessarily paralyzed with fright or resigned to an unavoidable fate. He may simply be unable to believe that the message of his eyes concerns him personally. It is all happening to somebody else.”

“So this, thought Jan, with a resignation that lay beyond all sadness, was the end of man. It was an end that no prophet had foreseen – an end that repudiated optimism and pessimism alike.Yet it was fitting: it had the sublime inevitability of a great work of art. Jan had glimpsed the universe in all its immensity, and knew now that it was no place for man. He realized at last how vain, in the ultimate analysis, had been the dream that lured him to the stars.For the road to the stars was a road that forked in two directions, and neither led to a goal that took any account of human hopes or fears.”

“As his body became more and more defenseless, so his means of offense became steadily more frightful.”

“There's no real objection to escapism, in the right places... We all want to escape occasionally. But science fiction is often very far from escapism, in fact you might say that science fiction is escape into reality... It's a fiction which does concern itself with real issues: the origin of man; our future. In fact I can't think of any form of literature which is more concerned with real issues, reality.”

“He felt like a young student again, confronted with all the art and knowledge of mankind. The experience was both exhilarating and depressing; a whole universe lay at his fingertips, but the fraction of it he could explore in an entire lifetime was so negligible that he was sometimes overwhelmed with despair.”

“He did not know that the Old One was his father, for such a relationship was utterly beyond his understanding, but as he looked at the emaciated body he felt a dim disquiet that was the ancestor of sadness.”

“Perhaps it is better to be un-sane and happy, than sane and un-happy. But it is the best of all to be sane and happy. Whether our descendants can achieve that goal will be the greatest challenge of the future. Indeed, it may well decide whether we have any future.”