"Some readers may realize that this story, first published in 1956, has been overtaken by events. In 1965, astronomers discovered that Mercury does not keep one side always to the Sun, but has a period of rotation of about fifty-four days, so that all parts of it are exposed to the sunlight at one time or another.Well, what can I do except say that I wish astronomers would get things right to begin with?And I certainly refuse to change the story to suit their whims."

"The saddest aspect of life right now is that science gathers knowledge faster than society gathers wisdom."

"There is a cult of ignorance in the United States, and there has always been. The strain of anti-intellectualism has been a constant thread winding its way through our political and cultural life, nurtured by the false notion that democracy means that my ignorance is just as good as your knowledge."

"He had read much, if one considers his long life; but his contemplation was much more than his reading. He was wont to say that if he had read as much as other men he should have known no more than other men."

"And now a hundred subjective years had passed in those hundred objective hours and he could no longer clearly visualize the university at all or the life of sad frustration he had been leading there toward the end."

"The human mind works at low efficiency. Twenty percent is the figure usually given. When, momentarily, there is a flash of greater power, it is termed a hunch, or insight, or intuition."

"Many years later he looked through one of my books and said, "How did you learn all this, Isaac?""From you, Pappa", I said."From me? I don't know any of this"."You didn't have to, Pappa", I said. "You valued learning and you taught me to value it. Once I learned to value it, the rest came without trouble."- Isaac Asimov (Isaak Yudovich Ozimov). It's been a good life."

"The troubles of modern life come from being divorced from nature."

"John Dalton's records, carefully preserved for a century, were destroyed during the World War II bombing of Manchester. It is not only the living who are killed in war."

"Meanwhile, fears of universal disaster sank to an all time low over the world."

"Self-education is, I firmly believe, the only kind of education there is."

"It is not only the living who are killed in war."

"I do not fear computers. I fear the lack of them."

"The action of social revolution and the reaction of guarding against such revolution or combating it once it has begun are the causes of a great deal of the human misery with which history is permeated."

"It is always useful, you see, to subject the past life of reform politicians to rather inquisitive research."

"Humanists recognize that it is only when people feel free to think for themselves, using reason as their guide, that they are best capable of developing values that succeed in satisfying human needs and serving human interests."

"If knowledge can create problems, it is not through ignorance that we can solve them."

"The Imperial forces must keep their hands off, but they find that they can do much even so. Each sector is encouraged to be suspicious of its neighbors. Within each sector, economic and social classes are encouraged to wage a kind of war with each other. The result is that all over Trantor it is impossible for the people to take united action. Everywhere, the people would rather fight each other than make a common stand against the central tyranny and the Empire rules without having to exert force."

"Whenever I have endured or accomplished some difficult task -- such as watching television, going out socially or sleeping -- I always look forward to rewarding myself with the small pleasure of getting back to my typewriter and writing something."

"I write for the same reason I breathe - because if I didn't, I would die."

"Goodbye, Hari, my love. Remember always--all you did for me. -I did nothing for you. -You loved me and your love made me--human."

"I tell you it's deadly when you start thinking your wife might be right."

"The stars, like dust, encircle meIn living mists of light;And all of space I seem to seeIn one vast burst of sight."

"The clown's eyes sidled towards her, then drew away quickly. "But they kept me away from you earlier-and, on my word, you may laugh, but I was lonely for missing friendship."

"I would argue that a truly developed country would be beyond Presidents and Kings. In a world with some semblance of equality, each liberal-minded woman, each gay person, and indeed almost every person could be their own President. In a world of equals, what real service does a ruler provide?"

"Mr Baley", said Quemot, "you can't treat human emotions as though they were built about a positronic brain"."I'm not saying you can. Robotics is a deductive science and sociology an inductive one. But mathematics can be made to apply in either case."

"I believe that only scientists can understand the universe. It is not so much that I have confidence in scientists being right, but that I have so much in nonscientists being wrong."

"People think of education as something they can finish."

"There's probably no one so easily bribed, but he lacks even the fundamental honesty of honorable corruption. He doesn't stay bribed; not for any sum."

"The Scientist - with capital letters and no smile."

"If my doctor told me I had only six minutes to live, I wouldn't brood. I'd type a little faster."

"It was obvious that bigotry was never a one-way operation, that hatred bred hatred!"

"It's the writing that teaches you."

"All normal life, Peter, consciously or otherwise, resent domination. If the domination is by an inferior, or by a supposed inferior, the resentment becomes stronger."

"In the empty expanses of space, the wandering traders need men like myself to care for the spiritual side of a life so given over to commerce, and worldly pursuits."

"Our lifetime may be the last that will be lived out in a technological society."

"I am not a speed reader. I am a speed understander."

"Despite all that education and experience can do, I retain a certain level of unsophistication that I cannot eradicate and that my friends find amusing. In fact, I think I sometimes detect conspiratorial plottings among my friends to protect me against my own lack of sophistication. I don't mind. I suspect that I am never quite as unsophisticated as they think I am, but I don't mind."

"It has been my philosophy of life that difficulties vanish when faced boldly."

"Bible: Various portions of it, when properly interpreted, contain a code of behaviour which many men consider best suited to the ultimate happiness of mankind."

"A subtle thought that is in error may yet give rise to fruitful inquiry that can establish truths of great value."

"To insult someone we call him "bestial." For deliberate cruelty and nature, "human" might be the greater insult."

"A person willing to fly in the face of reason, authority, and common sense must be a person of considerable self-assurance. Since he occurs only rarely, he must seem eccentric (in at least that respect) to the rest of us. A person eccentric in one respect is often eccentric in others."

"The first step in making rabbit stew is catching the rabbit."

"Were I to use the wits the Spirits gave me, then I would say this lady cannot exist - for what sane man would hold a dream to be reality. Yet rather would I not be sane and lend belief to charmed, enchanted eyes."

"There was no doubt about it: the City was the culmination of man's mastery over the environment. Not space travel, not the fifty colonized worlds that were now so haughtily independent, but the City."

"I made up my mind long ago to follow one cardinal rule in all my writing-to be clear. I have given up all thought of writing poetically or symbolically or experimentally, or in any of the other modes that might (if I were good enough) get me a Pulitzer prize. I would write merely clearly and in this way establish a warm relationship between myself and my readers, and the professional critics-Well, they can do whatever they wish."

"When I feel difficulty coming on I switch to another book I'm writing. When I get back to the problem my unconscious has solved it."

"Civilizations have always been pyramidal in structure. As one climbs toward the apex of the social edifice, there is increased leisure and increasing opportunity to pursue hapiness. As one climbs, one finds also fewer and fewer people to enjoy this more and more. Invariably, there is a preponderance of the dispossessed. And remember this, no matter how well off the bottom layers of the pyramid might be on an absolute scale, they are always dispossessed in comparison with the apex."

"No sensible decision can be made any longer without taking into account not only the world as it is, but the world as it will be."