Carl Sagan Quotes

A new consciousness is developing which sees the earth as a single organism and recognizes that an organism at war with itself is doomed. We are one planet.

Skeptical scrutiny is the means, in both science and religion, by which deep thoughts can be winnowed from deep nonsense.

One of the great commandments of science is, 'Mistrust arguments from authority'. (Scientists, being primates, and thus given to dominance hierarchies, of course do not always follow this commandment.)

What is called for is an exquisite balance between two conflicting needs: the most skeptical scrutiny of all hypotheses that are served up to us and at the same time a great openness to new ideas. If you are only skeptical, then no new ideas make it through to you. On the other hand, if you are open to the point of gullibility and have not an ounce of skeptical sense in you, then you cannot distinguish useful ideas from the worthless ones.

But I could be wrong.

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

The surface of the Earth is the shore of the cosmic ocean. On this shore, we've learned most of what we know. Recently, we've waded a little way out, maybe ankle-deep, and the water seems inviting. Some part of our being knows this is where we came from. We long to return, and we can, because the cosmos is also within us. We're made of star stuff. We are a way for the cosmos to know itself.

People are not stupid. They believe things for reasons. The last way for skeptics to get the attention of bright, curious, intelligent people is to belittle or condescend or to show arrogance toward their beliefs.

It will not be we who reach Alpha Centauri, and the other nearby stars. It will be a species very like us - but with more of our strengths and fewer of our weaknesses.

What counts is not what sounds plausible, not what we would like to believe, not what one or two witnesses claim, but only what is supported by hard evidence rigorously and skeptically examined. Extraordinary claims require extraordinary evidence.

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.

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

When Kepler found his long-cherished belief did not agree with the most precise observation, he accepted the uncomfortable fact. He preferred the hard truth to his dearest illusions, that is the heart of science.

Any sufficiently crisp question can be answered by a single binary digit-0 or 1, yes or no.

Real patriots ask questions.

I consider it an extremely dangerous doctrine, because the more likely we are to assume that the solution comes from the outside, the less likely we are to solve our problems ourselves.

I hold that popularization of science is successful if, at first, it does no more than spark the sense of wonder.

Science is not perfect. It's often misused; it's only a tool, but it's the best tool we have. Self-correcting , ever changing, applicable to everything: with this tool, we vanquish the impossible.

Anything else you're interested in is not going to happen if you can't breathe the air and drink the water. Don't sit this one out. Do something. You are by accident of fate alive at an absolutely critical moment in the history of our planet.

We go about our daily lives understanding almost nothing of the world.

How is it that hardly any major religion has looked at science and concluded, “This is better than we thought! The Universe is much bigger than our prophets said, grander, more subtle, more elegant?

Our species needs, and deserves, a citizenry with minds wide awake and a basic understanding of how the world works.

A blade of grass is a commonplace on Earth; it would be a miracle on Mars. Our descendants on Mars will know the value of a patch of green. And if a blade of grass is priceless, what is the value of a human being?

Science is merely an extremely powerful method of winnowing what's true from what feels good.

There are in fact 100 billion galaxies, each of which contain something like a 100 billion stars. Think of how many stars, and planets, and kinds of life there may be in this vast and awesome universe.

Ours is the first generation that has grown up with science-fiction ideas.

Has there ever been a religion with the prophetic accuracy and reliability of science? . . . No other human institution comes close.

We can always take but never give.

In the middle 1970s an astronomer I admire put together a modest manifesto called "Objections to Astrology" and asked me to endorse it. I struggled with his wording, and in the end found myself unable to sign, not because I thought astrology has any validity whatever, but because I felt (and still feel) that the tone of the statement was authoritarian.

In many cultures it is customary to answer that God created the universe out of nothing. But this is mere temporizing. If we wish courageously to pursue the question, we must, of course ask next where God comes from? And if we decide this to be unanswerable, why not save a step and conclude that the universe has always existed?

When permitted to listen to alternative opinions and engage in substantive debate, people have been known to change their minds. It can happen.

If we can't think for ourselves, if we're unwilling to question authority, then we're just putty in the hands of those in power.

We are made of star-stuff. Our bodies are made of star-stuff. There are pieces of star within us all.

Better by far to embrace the hard truth than a reassuring fable. If we crave some cosmic purpose, then let us find ourselves a worthy goal.

An organism at war with itself is doomed.

My wonder button is being pushed all the time.

Maxwell's Equations have had a greater impact on human history than any ten presidents.

The cosmos is full beyond measure of elegant truths; of exquisite interrelationships; of the awesome machinery of nature.

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

A religion old or new, that stressed the magnificence of the universe as revealed by modern science, might be able to draw forth reserves of reverence and awe hardly tapped by the conventional faiths. Sooner or later such a religion will emerge.

There are wonders enough out there without our inventing any.

Science is much more than a body of knowledge. It is a way of thinking. This is central to its success. Science invites us to let the facts in, even when they don't conform to our preconceptions. It counsels us to carry alternative hypotheses in our heads and see which ones best match the facts. It urges on us a fine balance between no-holds-barred openness to new ideas, however heretical, and the most rigorous skeptical scrutiny of everything - new ideas and established wisdom.

By exploring other worlds we safeguard this one. By itself, I think this fact more than justifies the money our species has spent in sending ships to other worlds. It is our fate to live during one of the most perilous and, at the same time, one of the most hopeful chapters in human history.

The cosmic calendar compresses the local history of the universe into a single year. If the universe began on January 1st it was not until May that the Milky Way formed. Other planetary systems may have appeared in June, July and August, but our Sun and Earth not until mid-September. Life arose soon after. We humans appear on the cosmic calendar so recently that our recorded history occupies only the last few seconds of the last minute of December 31st.

It is said that men may not be the dreams of the god, but rather that the gods are the dreams of men.

we make our world significant by the courage of our questions and the depth of our answers

That we can now think of no mechanism for astrology is relevant but unconvincing. No mechanism was known, for example, for continental drift when it was proposed by Wegener. Nevertheless, we see that Wegener was right, and those who objected on the grounds of unavailable mechanism were wrong.

Extinction is the rule. Survival is the exception.