It's my belief that the Universe possesses, in its essence, fractal properties of a very complex sort and that the pursuit of science shares those properties. It follows that any part of the Universe that remains un-understood, and any part of scientific investigation that remains unresolved, however small that might be in comparison to what is understood and resolved, contains within it all the complexity of the original. Therefore, we'll never finish. No matter how far we go, the road ahead will be as long as it was at the start, and that's the secret of the Universe.

Miniaturization doesn't actually make sense unless you miniaturize the very atoms of which matter is composed. Otherwise a tiny brain in a man the size of an insect, composed of normal atoms, is composed of too few atoms for the miniaturized man to be any more intelligent than the ant. Also, miniaturizing atoms is impossible according to the rules of quantum mechanics.

Modesty is an unnatural attitude, and one which is only with difficulty taught to children.

I am not a visual person. I have spent so many bounded years in my childhood that I have grown used to having books as my window on reality.

Writing is an addiction more powerful than alcohol, than nicotine, than crack. I could not conceive of not writing.

I am an atheist, out and out. It took me a long time to say it. I've been an atheist for years and years, but somehow I felt it was intellectually unrespectable to say one was an atheist, because it assumed knowledge that one didn't have. Somehow, it was better to say one was a humanist or an agnostic. I finally decided that I'm a creature of emotion as well as of reason. Emotionally, I am an atheist. I don't have the evidence to prove that God doesn't exist, but I so strongly suspect he doesn't that I don't want to waste my time.

I don't believe in an afterlife, so I don't have to spend my whole life fearing hell, or fearing heaven even more. For whatever the tortures of hell, I think the boredom of heaven would be even worse.

The most exciting phrase to hear in science, the one that heralds new discoveries, is not 'Eureka!', but 'That's funny ...'

People don't stop things they enjoy doing just because they reach a certain age. They don't stop playing tennis just because they turn 40, they don't stop with sex just because they turn 40; they keep it up as long as they can if they enjoy it, and learning will be the same thing.

The job of science will never be done, it will just sink deeper and deeper into never-ending complexity.

Titles are an important part of a story and I take considerable care in choosing one. In fact, I cannot start a story until I have chosen a title.

Self-preservation has frequently knuckled under to that tremendous yearning to get even.

Writing is hard work. The fact that I love doing it doesn't make it less hard work. People who love tennis will sweat themselves to exhaustion playing it, and the love of the game doesn't stop the sweating. The casual assumption that writers are unemployed bums because they don't go to the office and don't have a boss is something every writer has to live with. I have never known a writer who hasn't suffered as a result of this, hasn't resented it, and hasn't dreamed of murdering the next person who says "Boy, you've sure got it made. You just sit there and toss off a story or something whenever you feel like it."

Radiation, unlike smoking, drinking, and overeating, gives no pleasure, so the possible victims object.

Earth is a ball that is over 12,000 kilometres in diameter, and if it were modelled into an object the size of a billiard ball, with all its surface unevenness reproduced exactly to scale, the model would be smoother than an ordinary billiard ball and the ocean would be an all but unnoticeable mist of dampness over 70 percent of its surface.

A robot may not injure a human being, or, through inaction, allow a human being to come to harm.

Of all the cultural aspects of humanity, the only one which is not broken up into national or regional splinters is science. Different nations have different languages, they may have different religions, may have different dietaries, may have different holidays, different ways of thinking, but here's only one science. 

There are many aspects of the universe that still cannot be explained satisfactorily by science; but ignorance only implies ignorance that may someday be conquered. To surrender to ignorance and call it God has always been premature, and it remains premature today.

Ideas are cheap. It's only what you do with them that counts.

Once you've dissected a joke, you're about where you are when you've dissected a frog. It's dead. Banquets of the Black Widowers (1984), p. 49; comparable to "Humor can be dissected, as a frog can, but the thing dies in the process and the innards are discouraging to any but the pure scientific mind."

What a human being believes, however, no matter with what ardor, is not necessarily objective truth.

The fact is that I've never called myself a genius, and I think the term has been cheapened by overuse into meaninglessness. If other people want to call me that, that's their problem.

Books ... hold within them the gathered wisdom of humanity, the collected knowledge of the world's thinkers, the amusement and excitement built up by the imaginations of brilliant people. Books contain humor, beauty, wit, emotion, thought, and, indeed, all of life. Life without books is empty.

An optimistic view of the future would indicate that before long, the clear necessity of expanding humanity's horizons would cause ... space settlements to be built. The construction would also serve as a great project that not only would be clearly of great benefit, but might induce human cooperation in something large enough to fire the heart and mind, and make people forget the petty quarrels that have engaged them for thousands of years in wars over insignificant scraps of earthly territory.

A robot must obey the orders given it by human beings except where such orders would conflict with the First Law.

Science doesn't purvey absolute truth. Science is a mechanism. It's a way of trying to improve your knowledge of nature. It's a system for testing your thoughts against the universe and seeing whether they match. And this works, not just for the ordinary aspects of science, but for all of life. I should think people would want to know that what they know is truly what the universe is like, or at least as close as they can get to it.

There is no version of primeval history, preceding the discoveries of modern science, that is as rational and as inspiring as that of the first eleven chapters of the Book of Genesis.

Someone once asked me, "If you had your choice, Dr. Asimov, would it be women or writing?" My answer was, "Well, I can write for twelve hours at a time without getting tired."

In my fiction I am careful to make everything probable and to tie up all loose ends. Real life is not hampered by such considerations.

He could almost wish he were superstitious. He could then console himself with the thought that the casual meaningless meeting had really been directed by a knowing and purposeful Fate.

I joke sometimes to the effect that when I approach a part of a book where I must explain something I don't understand, I just type faster and faster and faster. Then, when I get to the part I don't understand, sheer inertia pushes me through. That's not literally true, of course, but there's something to it psychologically.

The foundation of all technology is fire.

Scientists have pushed back the horizon of time from the biblical 6,000 years to 4,600,000,000 years for the age of Earth a 760,000-fold increase.

A robot must protect its own existence as long as such protection does not conflict with the First or Second Laws.

The Law of conservation of energy tells us we can't get something for nothing, but we refuse to believe it.

The Bible and science agree in being unable to say anything certainly about what happened before the beginning. There is this difference. The Bible will never be able to tell us. It has reached its final form, and it simply doesn't say. Science, on the other hand, is still developing, and the time may come when it can answer questions that, at present, it cannot.

In the course of my fight with the school, I couldn't help but notice that I became a pariah. [...] Once, however, a fellow faculty member, making sure we were unobserved, said to me, "Isaac, the faculty is proud of you for your courage in fighting the administration for academic freedom."I said, "There's no courage involved in it. Don't you know my definition of academic freedom?""No. What's your definition of academic freedom?"I said, "Independent income."

Science fiction offers its writers chances of embarrassment that no other form of fiction does.

We face eternity now. We have no universe left, no outside phenomena, no emotions, no passions. Nothing but ourselves and thought. We face an eternity of introspection, when all through history we have never known what to do with ourselves on a rainy Sunday.

No matter how various the subject matter I write on, I was a science-fiction writer first and it is as a science-fiction writer that I want to be identified.

If anyone can be considered the greatest writer who ever lived, it is Shakespeare.

I get a certain pleasure in knowing that I live not merely in a city but in Manhattan, the center of New York City, a region so unique in many ways that I honestly believe that Earth is divided into halves: Manhattan and non-Manhattan.

If the love of money is the root of all evil, the need of money is most certainly the root of all despair.

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

If one thing goes without saying, almost anything can.

I was once being interviewed by Barbara Walters [...] In between two of the segments she asked me [...] "But what would you do if the doctor gave you only six months to live?" I said, "Type faster." This was widely quoted, but the "six months" was changed to "six minutes," which bothered me. It's "six months."

There is more to a science fiction story than the science it contains.

The Dantean conceptions of Inferno were childish and unworthy of the Divine imagination: fire and torture. Boredom is much more subtle. The inner torture of a mind unable to escape itself in any way, condemned to fester in its own exuding mental pus for all time, is much more fitting. Oh, yes, my friend, we have been judged, and condemned, too, and this is not Heaven, but hell.

Of all the books I have ever worked on, I think Asimov's Guide to Shakespeare gave me the most pleasure, day in, day out. For months and months I lived and thought Shakespeare, and I don't see how there can be any greater pleasure in the world, any pleasure, that is, that one can indulge in for as much as ten hours without pause, day after day indefinitely.

Scientific theories can always be improved and are improved. That is one of the glories of science. It is the authoritarian view of the Universe that is frozen in stone and cannot be changed, so that once it is wrong, it is wrong forever.