Quotes from Carl Sagan

An organism at war with itself is doomed.

There are no forbidden questions in science, no matters too sensitive or delicate to be probed, no sacred truths.

Knowing a great deal is not the same as being smart; intelligence is not information alone but also judgement, the manner in which information is coordinated and used.

The Cosmos is all that is or ever was or ever will be.

Think of the rivers of blood spilled by all those generals and emperors so that in glory and in triumph they could become the 'Momentary' masters of a 'Fraction' of a 'Dot'

One of the reasons for its success is that science has a built-in, error-correcting machinery at its very heart. Some may consider this an overbroad characterization, but to me every time we exercise self-criticism, every time we test our ideas against the outside world, we are doing science. When we are self-indulgent and uncritical, when we confuse hopes and facts, we slide into pseudoscience and superstition.

Science is based on experiment, on a willingness to challenge old dogma, on an openness to see the universe as it really is. Accordingly, science sometimes requires courage - at the very least the courage to question the conventional wisdom.

To live in the hearts we leave behind is to live forever.

If God is omnipotent and omniscient, why didn't he start the universe out in the first place so it would come out the way he wants? Why's he constantly repairing and complaining? No, there's one thing the Bible makes clear: The biblical God is a sloppy manufacturer. He's not good at design, he's not good at execution. He'd be out of business, if there was any competition.

We live on a hunk of rock and metal that circles a humdrum star that is one of 400 billion other stars that make up the Milky Way Galaxy which is one of billions of other galaxies which make up a universe which may be one of a very large number, perhaps an infinite number, of other universes. That is a perspective on human life and our culture that is well worth pondering.

The visions we offer our children shape the future. It _matters_ what those visions are. Often they become self-fulfilling prophecies. Dreams are maps.

What a marvelous cooperative arrangement - plants and animals each inhaling each other's exhalations, a kind of planet-wide mutual mouth-to-stoma resuscitation, the entire elegant cycle powered by a star 150 million kilometers away.

Any faith that admires truth, that strives to know God, must be brave enough to accommodate the universe.

If we continue to accumulate only power and not wisdom, we will surely destroy ourselves. Our very existence in that distant time requires that we will have changed our institutions and ourselves. How can I dare to guess about humans in the far future? It is, I think, only a matter of natural selection. If we become even slightly more violent, shortsighted, ignorant, and selfish than we are now, almost certainly we will have no future.

The visions we offer our children shape the future.

We have begun to contemplate our origins: starstuff pondering the stars; organized assemblages of ten billion billion billion atoms considering the evolution of atoms; tracing the long journey by which, here at least, consciousness arose.

When we look up at night and view the stars, everything we see is shinning because of distant nuclear fusion.

The lifetime of a human being is measured by decades, the lifetime of the Sun is a hundred million times longer. Compared to a star, we are like mayflies, fleeting ephemeral creatures who live out their lives in the course of a single day.

We can't help it. Life looks for life.

At the heart of science is an essential balance between two seemingly contradictory attitudes--an openness to new ideas, no matter how bizarre or counterintuitive they may be, and the most ruthless skeptical scrutiny of all ideas, old and new. This is how deep truths are winnowed from deep nonsense.

Those at too great a distance may, I am well are, mistake ignorance for perspective.

But I try not to think with my gut. If I'm serious about understanding the world, thinking with anything besides my brain, as tempting as that might be, is likely to get me into trouble.

We are the local embodiment of a Cosmos grown to self-awareness. We have begun to contemplate our origins: starstuff pondering the stars; organized assemblages of ten billion billion billion atoms considering the evolution of atoms; tracing the long journey by which, here at least, consciousness arose. 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 humans look rather different from a tree. Without a doubt we perceive the world differently than a tree does. But down deep, at the molecular heart of life, the trees and we are essentially identical.