UFOs: The reliable cases are uninteresting and the interesting cases are unreliable.
CARL SAGAN, Other Worlds
For me, it is far better to grasp the Universe as it really is than to persist in delusion, however satisfying and reassuring.
CARL SAGAN, The Demon-Haunted World: Science as a Candle in the Dark
The universe was made on purpose, the circle said. In whatever galaxy you happen to find yourself, you take the circumference of a circle, divide it by its diameter, measure closely enough, and uncover a miracle — another circle, drawn kilometers downstream of the decimal point. There would be richer messages farther in. It doesn't matter what you look like, or what you're made of, or where you come from. As long as you live in this universe, and have a modest talent for mathematics, sooner or later you'll find it. It's already here. It's inside everything. You don't have to leave your planet to find it. In the fabric of space and in the nature of matter, as in a great work of art, there is, written small, the artist’s signature. Standing over humans, gods, and demons, subsuming Caretakers and Tunnel builders, there is an intelligence that antedates the universe.
CARL SAGAN, Contact: A Novel
I know that science and technology are not just cornucopias pouring good deeds out into the world. Scientists not only conceived nuclear weapons; they also took political leaders by the lapels, arguing that their nation -- whichever it happened to be -- had to have one first.... There's a reason people are nervous about science and technology ... the image of the mad scientist haunts our world--from Dr. Faust to Dr. Frankenstein to Dr. Strangelove to the white-coated loonies of Saturday morning children's television. (All this doesn't inspire budding scientists.) But there's no way back. We can't just conclude that science puts too much power into the hands of morally feeble technologists or corrupt, power-crazed politicians and decide to get rid of it. Advances in medicine and agriculture have saved more lives than have been lost in all the wars in history. Advances in transportation, communication, and entertainment have transformed the world. The sword of science is double-edged. Rather, its awesome power forces on all of us, including politicians, a new responsibility -- more attention to the long-term consequences of technology, a global and transgenerational perspective, an incentive to avoid easy appeals to nationalism and chauvinism. Mistakes are becoming too expensive.
CARL SAGAN, "Why We Need to Understand Science", Skeptical Inquirer, spring 1990
The fact that some geniuses were laughed at does not imply that all who are laughed at are geniuses. They laughed at Columbus, they laughed at Fulton, they laughed at the Wright brothers. But they also laughed at Bozo the Clown.
CARL SAGAN, Broca's Brain: Reflections on the Romance of Science
Finding out the way the world really works requires a mix of hunches, intuition and brilliant creativity; it also requires skeptical scrutiny of every step.
CARL SAGAN, Broca's Brain: Reflections on the Romance of Science
We live in a society exquisitely dependent on science and technology, in which hardly anyone knows anything about science and technology.
CARL SAGAN, "Why We Need to Understand Science", Skeptical Inquirer, spring 1990
The success of science, both its intellectual excitement and its practical application, depend upon the self-correcting character of science. There must be a way of testing any valid idea. It must be possible to reproduce any valid experiment. The character or beliefs of the scientists are irrelevant; all that matters is whether the evidence supports his contention.
CARL SAGAN, Broca's Brain: Reflections on the Romance of Science
The chief deficiency I see in the skeptical movement is its polarization: Us vs. Them -- the sense that we have a monopoly on the truth; that those other people who believe in all these stupid doctrines are morons; that if you're sensible, you'll listen to us; and if not, to hell with you. This is nonconstructive. It does not get our message across. It condemns us to permanent minority status.
CARL SAGAN, The Demon-Haunted World: Science as a Candle in the Dark
In science it often happens that scientists say, 'You know that's a really good argument; my position is mistaken,' and then they would actually change their minds and you never hear that old view from them again. They really do it. It doesn't happen as often as it should, because scientists are human and change is sometimes painful. But it happens every day. I cannot recall the last time something like that happened in politics or religion.
CARL SAGAN, Keynote address to the Committee for the Scientific Investigation of Claims of the Paranormal, 1987
It seems to me 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 ideas. If you are only skeptical, then no new ideas make it through to you. You become a crotchety old person convinced that nonsense is ruling the world. (There is, of course, much data to support you.) But every now and then, a new idea turns out to be on the mark, valid and wonderful. If you are too much in the habit of being skeptical about everything, you are going to miss or resent it, and either way you will be standing in the way of understanding and progress. 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.
CARL SAGAN, "The Burden of Skepticism"
Across the sea of space, the stars are other suns.
CARL SAGAN, Cosmos
Science is not only compatible with spirituality; it is a profound source of spirituality.
CARL SAGAN, The Demon-Haunted World: Science as a Candle in the Dark
There is every reason to think that in the coming years Mars and its mysteries will become increasingly familiar to the inhabitants of the Planet Earth.
CARL SAGAN, Pale Blue Dot
It is clear from the fossil record that almost every species that has ever existed is extinct; extinction is the rule, survival is the exception. And no species is guaranteed its tenure on this planet.
CARL SAGAN, The Varieties of Scientific Experience: A Personal View of the Search for God
Now, another way of looking at this is as a conflict within the human heart, as a conflict between the bureaucratic, hierarchical, aggressive parts of our nature, which in a neurophysiological sense we share with our reptilian ancestors, and the other parts of our nature, the generalized capacity for love, for compassion, for identification with others who may superficially not look or talk or act or dress exactly like us, the ability to figure the world out that is focused and concentrated in our cerebral cortex. Our survival is (how could we have imagined it to be anything else?) a reflection of our own nature and how we manage these contending tendencies within the human heart and mind.
CARL SAGAN, The Varieties of Scientific Experience: A Personal View of the Search for God
Other things being equal, if you can figure the world out, you have a better chance of survival. At least until the invention of nuclear weapons.
CARL SAGAN, The Varieties of Scientific Experience: A Personal View of the Search for God
Once you give a charlatan power over you, you almost never get it back.
CARL SAGAN, The Demon-Haunted World
One of the saddest lessons of history is this: If we've been bamboozled long enough, we tend to reject any evidence of the bamboozle. We're no longer interested in finding out the truth. The bamboozle has captured us.
CARL SAGAN, The Demon-Haunted World
I don't know why you're on Mars. Maybe you're there because we recognize we have to carefully move small asteroids around to avert the possibility of one impacting the Earth with catastrophic consequences, and while we're up in near-Earth space, it's only a hop, skip, and a jump to Mars. Or maybe we're on Mars because we recognize that if there are human communities on many different worlds, the chances of us being rendered extinct by some catastrophe on one world is much less. Or maybe we're on Mars because of the magnificent science that can be done there, that the gates of the wonder world are opening in our time. Or maybe we're on Mars because we have to be, because there's a deep nomadic impulse built into us by the evolutionary process. We come, after all, from hunter-gatherers, and for 99.9% of our tenure on Earth we've been wanderers. And, the next place to wander to is Mars. But whatever the reason you're on Mars is, I'm glad you're there. And I wish I was with you.
CARL SAGAN, attributed, Going to Mars: The Stories Of The People Behind NASA's Mars Missions Past, Present, and Future
The Cosmos is all that is or was or ever will be. Our feeblest contemplations of the Cosmos stir us -- there is a tingling in the spine, a catch in the voice, a faint sensation, as if a distant memory, of falling from a height. We know we are approaching the greatest of mysteries.
CARL SAGAN, Cosmos
Every one of us is, in the cosmic perspective, precious. If a human disagrees with you, let him live. In a hundred billion galaxies, you will not find another.
CARL SAGAN, Cosmos