Carl Sagan - Earth Quotes

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

Carl Sagan
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.

Carl Sagan
When you make the finding yourself - even if you're the last person on Earth to see the light - you'll never forget it.

Carl Sagan
Let's go back to the solar nebula... with the temperature declining the farther we get from the Sun.... at different distances from the Sun, different materials will condense out, because they have different vapor pressures or different melting points.... water condenses out roughly at the vicinity of the Earth, whereas silicates condense out closer to the Sun... you have to go out to somewhere near the present distance of Saturn before methane condenses.

Carl Sagan
There is no other species on the 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 two rules. First: there are no sacred truths; all assumptions must be critically examined; arguments from authority are worthless. Second: whatever is inconsistent with the facts must be discarded or revised. We must understand the Cosmos as it is and not confuse how it is with how we wish it to be.

Carl Sagan
The beauty of a living thing is not the atoms that go into it, but the way those atoms are put together. Information distilled over 4 billion years of biological evolution. Incidentally, all the organisms on the Earth are made essentially of that stuff. An eyedropper full of that liquid could be used to make a caterpillar or a petunia if only we knew how to put the components together.

Carl Sagan
We are the local embodiment of a Cosmos grown to selfawareness. 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.

Carl Sagan
Philosophers and scientists confidently offer up traits said to be uniquely human, and the monkeys and apes casually knock them down — toppling the pretension that humans constitute some sort of biological aristocracy among the beings on Earth.

Carl Sagan
The major religions on the Earth contradict each other left and right. You can't all be correct. And what if all of you are wrong? It's a possibility, you know. You must care about the truth, right? Well, the way to winnow through all the differing contentions is to be skeptical. I'm not any more skeptical about your religious beliefs than I am about every new scientific idea I hear about. But in my line of work, they're called hypotheses, not inspiration and not revelation.

Carl Sagan
When you look more generally at life on Earth, you find that it is all the same kind of life.... It uses about fifty fundamental biological building blocks, organic molecules.... with trivial exceptions, all organisms on Earth use... an enzyme, to control the rate and direction of the chemistry of life.... a nucleic acid to encode the hereditary information... the identical code book for translating nucleic acid language into protein language.... At the molecular level, we are all virtually identical.

Carl Sagan
Appeal to ignorance — the claim that whatever has not been proved false must be true, and vice versa (e. g. There is no compelling evidence that UFOs are not visiting the Earth; therefore UFOs exist — and there is intelligent life elsewhere in the universe. Or: There may be seventy kazillion other worlds, but not one is known to have the moral advancement of the Earth, so we're still central to the Universe.) This impatience with ambiguity can be criticized in the phrase: absence of evidence is not evidence of absence.

Carl Sagan
The Earth is a very small stage in a vast cosmic arena.

Carl Sagan
If we are to survive, our loyalties must be broadened further, to include the whole human community, the entire planet Earth. Many of those who run the nations will find this idea unpleasant.

Carl Sagan
The Platonists and their Christian successors held the peculiar notion that the Earth was tainted and somehow nasty, while the heavens were perfect and divine. The fundamental idea that the Earth is a planet, that we are citizens of the Universe, was rejected and forgotten.

Carl Sagan
The amount of organic matter that could have been produced in the first few hundred million years of Earth history was sufficient to have produced in the present ocean a several-percent solution of organic matter. This is just about the dilution of Knorr's chicken soup, and not that different from the composition either. And chicken soup is widely known to be good for life.

Carl Sagan
If we keep on with business as usual, the Earth will be warmed more every year; drought and floods will be endemic; many more cities, provinces, and whole nations will be submerged beneath the waves — unless heroic worldwide engineering countermeasures are taken. In the longer run, still more dire consequences may follow, including the collapse of the West Antarctic ice sheet, and the inundation of almost all the coastal cities on the planet.

Carl Sagan
The Earth is the only world known so far to harbor life. There is nowhere else, at least in the near future, to which our species could migrate. Visit, yes. Settle, not yet. Like it or not, for the moment the Earth is where we make our stand.

Carl Sagan