Quotes by Carl Sagan

The vast distances that separate the stars are providential. Beings and worlds are quarantined from one another. The quarantine is lifted only for those with sufficient self-knowledge and judgment to have safely traveled from star to star.

In all our searching, the only thing weve found that makes the emptiness bearable is each other.

Since, in the long run, every planetary civilization will be endangered by impacts from space, every surviving civilization is obliged to become spacefaring--not because of exploratory or romantic zeal, but for the most practical reason imaginable: staying alive... If our long-term survival is at stake, we have a basic responsibility to our species to venture to other worlds.

While ritual, emotion and reasoning are all significant aspects of human nature, the most nearly unique human characteristic is the ability to associate abstractly and to reason. Curiosity and the urge to solve problems are the emotional hallmarks of our species; and the most characteristically human activities are mathematics, science, technology, music and the arts--a somewhat broader range of subjects than is usually included under the humanities. Indeed, in its common usage this very word seems to reflect a peculiar narrowness of vision about what is human. Mathematics is as much a humanity as poetry.

There is no other species on Earth that does science. It is, so far, entirely a human invention, evolved by natural selection in the cerebral cortex for one simple reason: it works. It is not perfect. It can be misused. It is only a tool. But it is by far the best tool we have, self-correcting, ongoing, applicable to everything.

It has been said that astronomy is a humbling and character-building experience. There is perhaps no better demonstration of the folly of human conceits than this distant image of our tiny world. To me, it underscores our responsibility to deal more kindly with one another and to preserve and cherish the pale blue dot, the only home weve ever known.

Fireflies out on a warm summers night, seeing the urgent, flashing, yellow-white phosphorescence below them, go crazy with desire; moths cast to the winds an enchantment potion that draws the opposite sex, wings beating hurriedly, from kilometers away; peacocks display a devastating corona of blue and green and the peahens are all aflutter; competing pollen grains extrude tiny tubes that race each other down the female flowers orifice to the waiting egg below; luminescent squid present rhapsodic light shows, altering the pattern, brightness and color radiated from their heads, tentacles, and eyeballs; a tapeworm diligently lays a hundred thousand fertilized eggs in a single day; a great whale rumbles through the ocean depths uttering plaintive cries that are understood hundreds of thousands of kilometers away, where another lonely behemoth is attentively listening; bacteria sidle up to one another and merge; cicadas chorus in a collective serenade of love; honeybee couples soar on matrimonial flights from which only one partner returns; male fish spray their spunk over a slimy clutch of eggs laid by God-knows-who; dogs, out cruising, sniff each others nether parts, seeking erotic stimuli; flowers exude sultry perfumes and decorate their petals with garish ultraviolet advertisements for passing insects, birds, and bats; and men and women sing, dance, dress, adorn, paint, posture, self-mutilate, demand, coerce, dissemble, plead, succumb, and risk their lives. To say that love makes the world go around is to go too far. The Earth spins because it did so as it was formed and there has been nothing to stop it since. But the nearly maniacal devotion to sex and love by most of the plants, animals, and microbes with which we are familiar is a pervasive and striking aspect of life on Earth. It cries out for explanation. What is all this in aid of? What is the torrent of passion and obsession about? Why will organisms go without sleep, without food, gladly put themselves in mortal danger for sex? ... For more than half the history of life on Earth organisms seem to have done perfectly well without it. What good is sex?... Through 4 billion years of natural selection, instructions have been honed and fine-tuned...sequences of As, Cs, Gs, and Ts, manuals written out in the alphabet of life in competition with other similar manuals published by other firms. The organisms become the means through which the instructions flow and copy themselves, by which new instructions are tried out, on which selection operates. The hen, said Samuel Butler, is the eggs way of making another egg. It is on this level that we must understand what sex is for. ... The sockeye salmon exhaust themselves swimming up the mighty Columbia River to spawn, heroically hurdling cataracts, in a single-minded effort that works to propagate their DNA sequences into future generation. The moment their work is done, they fall to pieces. Scales flake off, fins drop, and soon--often within hours of spawning--they are dead and becoming distinctly aromatic. Theyve served their purpose. Nature is unsentimental. Death is built in.

The brain is like a muscle. When it is in use we feel very good. Understanding is joyous.

She had to fight against developing too combative a personality or becoming altogether a misanthrope. She suddenly caught herself. Misanthrope is someone who dislikes everybody, not just men.And they certainly had a word for someone who hates women: misogynist. But the male lexicographers had somehow neglected to coin a word for the dislike of men. They were almost entirely men themselves, she thought, and had been unable to imagine a market for such a word.

Might it be possible at some future time, when neurophysiology has advanced substantially, to reconstruct the memories or insight of someone long dead?...It would be the ultimate breach of privacy.

The price we pay for the anticipation of our future is anxiety about it.

As a consequence of the enormous social and technological changes of the last few centuries, the world is not working well. We do not live in traditional and static societies. But our government, in resisting change, act as if we did. Unless we destroy ourselves utterly, the future belongs to those societies that, while not ignoring the reptilian and mammalian parts of our being, enable the characteristically human components of our nature to flourish; to those societies that encourage diversity rather than conformity; to those societies willing to invest resources in a variety of social, political, economic and cultural experiments, and prepared to sacrifice short-term advantage for long-term benefit; to those societies that treat new ideas as delicate, fragile and immensely valuable pathways to the future.

I worry that, especially as the Millennium edges nearer, pseudoscience and superstition will seem year by year more tempting, the siren song of unreason more sonorous and attractive. Where have we heard it before? Whenever our ethnic or national prejudices are aroused, in times of scarcity, during challenges to national self-esteem or nerve, when we agonize about our diminished cosmic place and purpose, or when fanaticism is bubbling up around us - then, habits of thought familiar from ages past reach for the controls.The candle flame gutters. Its little pool of light trembles. Darkness gathers. The demons begin to stir.

When I wake up I go through an abbreviated process of mourning all over again. Plainly, there’s something within me that’s ready to believe in life after death. And it’s not the least bit interested in whether there’s any sober evidence for it.

Their position seems to be that their God is so great he doesnt even have to exist.

Sometimes she would be engaged in a laboratory exercise or a seminar when the instructor would say, Gentlemen, lets proceed, and sensing Ellies frown would add, Sorry, Miss Arroway, but I think of you as one of the boys. The highest compliment they were capable of paying was that in their minds she was not overtly female.

If you want to save your child from polio, you can pray or you can inoculate. ... Choose science.

For thousands of years humans were oppressed— as some of us still are— by the notion that the universe is a marionette whose strings are pulled by a god or gods, unseen and inscrutable. Then, 2,500 years ago, there was a glorious awakening in Ionia: on Samos and the other nearby Greek colonies that grew up among the islands and inlets of the busy eastern Aegean Sea. Suddenly there were people who believed that everything was made of atoms; that human beings and other animals had sprung from simpler forms; that diseases were not caused by demons or the gods; that the Earth was only a planet going around the Sun. And that the stars were very far away.

There is a wide yawning black infinity. In every direction the extension is endless, the sensation of depth is overwhelming. And the darkness is immortal. Where light exists, it is pure, blazing, fierce; but light exists almost nowhere, and the blackness itself is also pure and blazing and fierce. But most of all, there is very nearly nothing in the dark; except for little bits here and there, often associated with the light, this infinite receptacle is empty.This picture is strangely frightening. It should be familiar. It is our universe.Even these stars, which seem so numerous, are, as sand, as dust, or less than dust, in the enormity of the space in which there is nothing. Nothing! We are not without empathetic terror when we open Pascal’s Pensées and read, I am the great silent spaces between wo

Imagination will often carry us to worlds that never were, but without it we go nowhere.