Top 610 Quotes & Sayings by Carl Sagan - Page 10

The secrets of evolution are death and time-the deaths of enormous numbers of lifeforms that were imperfectly adapted to the environment; and time for a long succession of small mutations.

Eratosthenes was the director of the great library of Alexandria, the Centre of science and learning in the ancient world. Aristotle had argued that humanity was divided into Greeks and everybody else, whom he called barbarians and that the Greeks should keep themselves racially pure. He thought it was fitting for the Greeks to enslave other peoples. But Erathosthenes criticized Aristotle for his blind chauvinism, he believed there was good and bad in every nation.

What an astonishing thing a book is.

You mustn't think of the Universe as a wilderness. It hasn't been that for billions of years," he said. "Think of it more as... ..cultivated.

When a honeybee dies it releases a death pheromone, a characteristic odour that signals the survivors to remove it from the hive. The corpse is promptly pushed and tugged out of the hive. The death pheromone is oleic acid. What happens if a live bee is dabbed with a drop of oleic acid? Then no matter how strapping and vigourous it might be, it is carried kicking and screaming out of the hive.

Teller contended, not implausibly, that hydrogen bombs keep the peace, or at least prevent thermonuclear war, because the consequences of warfare between nuclear powers are now too dangerous. We haven't had a nuclear war yet, have we? But all such arguments assume that the nuclear-armed nations are and always will be, without exception, rational actors, and that bouts of anger and revenge and madness will never overtake their leaders (or military and secret police officers in charge of nuclear weapons). In the century of Hitler and Stalin, this seems ingenuous.

For myself, I like a universe that, includes much that is unknown and, at the same time, much that is knowable. A universe in which everything is known would be static and dull, as boring as the heaven of some weak-minded theologians. A universe that is unknowable is no fit place for a thinking being. The ideal universe for us is one very much like the universe we inhabit. And I would guess that this is not really much of a coincidence.

Books permit us to voyage through time, to tap the wisdom of our ancestors.

In the long run, the aggressive civilizations destroy themselves, almost always. It's their nature. They can't help it.

(When asked merely if they accept evolution, 45 percent of Americans say yes. The figure is 70 percent in China.) When the movie Jurassic Park was shown in Israel, it was condemned by some Orthodox rabbis because it accepted evolution and because it taught that dinosaurs lived a hundred million years ago-when, as is plainly stated at every Rosh Hashonhan and every Jewish wedding ceremony, the Universe is less than 6,000 years old.

Humans are very good at dreaming, although you'd never know it from your television.

In more than one respect, the exploring of the Solar System and homesteading other worlds constitutes the beginning, much more than the end, of history.

We need to reduce military budgets; raise living standards; engender respect for learning; support science, scholarship, invention, and industry; promote free inquiry; reduce domestic coercion; involve the workers more in managerial decisions; and promote genuine respect and understanding derived from an acknowledgement of our common humanity and our common jeopardy.

If we teach only the findings and products of science - no matter how useful and even inspiring they may be - without communicating its critical method, how can the average person possibly distinguish science from pseudoscience?

A single message from space will show that it is possible to live through technological adolescence. . . . It is possible that the future of human civilization depends on the receipt of interstellar messages.

We can make a similar examination, but with greater uncertainty, of the extraterrestrial hypothesis that holds that a wide range of UFOs viewed on the planet Earth are space vehicles from planets of other stars.

...the idea of a spiritual part of our nature that survives death, the notion of an afterlife, ought to be easy for religions and nations to sell. This is not an issue of which we might anticipate widespread skepticism. People will want to believe it, even if the evidence is meager to nil... compelling testimony ... provides that our personality, character, memory ... resides in the matter of the brain, it is easy not to focus on it, to find ways to evade the weight of the evidence.

For years I've been stressing with regard to UFOs that extraordinary claims require extraordinary evidence.

We are the children equally of the Sky and the Earth.

He sought a way to preserve the past. John Hershel was one of the founders of a new form of time travel.... a means to capture light and memories. He actually coined a word for it... photography. When you think about it, photography is a form of time travel. This man is staring at us from across the centuries, a ghost preserved by light.

I went to the librarian and asked for a book about stars.... And the answer was stunning. It was that the Sun was a star but really close. The stars were suns, but so far away they were just little points of light.... The scale of the universe suddenly opened up to me. It was a kind of religious experience. There was a magnificence to it, a grandeur, a scale which has never left me. Never ever left me.

What does it mean for a civilisation to be a million years old? We have had radio telescopes and spaceships for a few decades; our technical civilisation is a few hundred years old ... an advanced civilisation millions of years old is as much beyond us as we are beyond a bushbaby or a macaque

One trend that bothers me is the glorification of stupidity, that the media is reassuring people it's alright not to know anything. That to me is far more dangerous than a little pornography on the Internet.

Those with the courage to explore the weave and structure of the Cosmos, even where it differs profoundly from their wishes and prejudices, will penetrate its deepest mysteries.

But amid much elegance and precision, the details of life and the Universe also exhibit haphazard, jury-rigged arrangements and much poor planning. What shall we make of this: an edifice abandoned early in construction by the architect?

Societies will, of course, wish to exercise prudence in deciding which technologies that is, which applications of science are to be pursued and which not. But without funding basic research, without supporting the acquisition of knowledge for its own sake, our options become dangerously limited.

Our loyalties are to the species and the planet. We speak for Earth.

[S]cience has itself become a kind of religion.

I don?t feel rejected by the sky. I?m a part of it- tiny, to be sure, but everything is tiny compared to that overwhelming immensity.

If you want to make a [rhubarb] pie from scratch, first you have to create the universe.

Discussing the possibilities of extraterrestrial life: I would love it even if they were short, sullen, grumpy and sexually obsessed. But there just isn't any good evidence.

Maybe it's a little early. Maybe the time is not quite yet. But those other worlds - promising untold opportunities - beckon. Silently, they orbit the Sun, waiting.

The cannabis experience has greatly improved my appreciation for art, a subject which I had never much appreciated before.

The reappearance of the crescent moon after the new moon; the return of the Sun after a total eclipse, the rising of the Sun in the morning after its troublesome absence at night were noted by people around the world; these phenomena spoke to our ancestors of the possibility of surviving death. Up there in the skies was also a metaphor of immortality.

In our time, we have sifted the sands of Mars, we have established a presence there, we have fulfilled a century of dreams!

In exchange for freedom of inquiry, scientists are obliged to explain their work.

[N]o scientist likes to be criticized. ... But you don't reply to critics: "Wait a minute, wait a minute; this is a really good idea. I'm very fond of it. It's done you no harm. Please don't attack it." That's not the way it goes. The hard but just rule is that if the ideas don't work, you must throw them away. Don't waste any neurons on what doesn't work. Devote those neurons to new ideas that better explain the data. Valid criticism is doing you a favor.

If the greenhouse effect is a blanket in which we wrap ourselves to keep warm, nuclear winter kicks the blanket off.

Every thinking person fears nuclear war, and every technological state plans for it. Everyone knows it is madness, and every nation has an excuse

And after we returned to the savannahs and abandoned the trees, did we long for those great graceful leaps and ecstatic moments of weightlessness in the shafts of sunlight of the forest roof?

Human beings grew up in forests; we have a natural affinity for them. How lovely a tree is, straining toward the sky.

A tiny blue dot set in a sunbeam. Here it is. That's where we live. That's home. We humans are one species and this is our world. It is our responsibility to cherish it. Of all the worlds in our solar system, the only one so far as we know, graced by life.

Nobody listens to mathematicians.

Centuries hence, when current social and political problems may seem as remote as the problems of the Thirty Years' War are to us, our age may be remembered chiefly for one fact: It was the time when the inhabitants of the earth first made contact with the vast cosmos in which their small planet is embedded.

Time spent with children is time well spent. Their little minds are not constrained by 'reality' or focused upon goals. Anything and everything is possible. Imagination will often carry us to worlds that never were. But without it we go nowhere.

It means nothing to be open to a proposition we don't understand.

[One's] inability to invalidate your hypothesis is not at all the same thing as proving it true.

In a lot of scientists, the ratio of wonder to skepticism declines in time. That may be connected with the fact that in some fields-mathematics, physics, some others-the great discoveries are almost entirely made by youngsters.

This oak tree and me, we're made of the same stuff.

Who will speak for Planet Earth?

Billions and billions.

Probably a dozen times since their death I've heard my mother or father, in an ordinary conversational tone of voice, call my name. They had called my name often during my life with them ... It doesn't seem strange to me.

I don't know the answer. Maybe no one knows. Maybe when you grow up, you'll be the first to find out.

We are, in a way, temporary ambulatory repositories for our nucleic acids. This does not deny our humanity; it does not prevent us from pursuing the good, the true and the beautiful. But it would be a great mistake to ignore where we have come from in our attempt to determine where we are going.

We are an intelligent species and the use of our intelligence quite properly gives us pleasure. In this respect the brain is like a muscle. When we think well, we feel good. Understanding is a kind of ecstasy.

There is a lurking fear that some things are not “meant" to be known, that some inquiries are too dangerous for human beings to make.

The universe forces those who live in it to understand it.

Our loyalties are to the species and the planet. We speak for Earth. Our obligation to survive is owed not just to ourselves but also to that Cosmos, ancient and vast, from which we spring.

We are at a crossroads in human history. Never before has there been a moment so simultaneously perilous and promising. We are the first species to have taken evolution into our own hands.

The desire to be connected with the cosmos reflects a profound reality, but we are connected; not in the trivial ways that astrology promises, but in the deepest ways.