Carl Sagan - Human Quotes

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Thus the recent rapid evolution of human intelligence is not only the cause of but also the only conceivable solution to the many serious problems that beset us.

Carl Sagan
Virtually every major technological advance in the history of the human species - back to the invention of stone tools and the domestication of fire - has been ethically ambiguous.

Carl Sagan
Relativity does set limits on what humans can ultimately do. But the universe is not required to be in perfect harmony with human aspirations.

Carl Sagan
I think the most significant creative activities of our or any other human culture — legal and ethical systems, art and music, science and technology — were made possible only through the collaborative work of the left and right cerebral hemispheres...We might say that human culture is the function of corpus callosum.

Carl Sagan
Instead of wanting everyone to share and know of their discoveries the Pythagoreans suppressed the square root of two and the dodecahedron. The outside world was not to know. The Pythagoreans had discovered, in the mathematical underpinnings of nature, one of the two most powerful scientific tools, the other of course is experiment, but instead of using their insight to advance the collective voyage of human discovery they made of it little more than the hocus-pocus of a mystery cult. Science and mathematics were to be removed from the hands of the merchants and the artisans.

Carl Sagan
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
The size and age of the Cosmos are beyond ordinary human understanding. Lost somewhere between immensity and eternity is our tiny planetary home. In a cosmic perspective, most human concerns seem insignificant, even petty. And yet our species is young and curious and brave and shows much promise. In the last few millennia we have made the most astonishing and unexpected discoveries about the Cosmos and our place within it, explorations that are exhilarating to consider. They remind us that humans have evolved to wonder, that understanding is a joy, that knowledge is prerequisite to survival. I believe our future depends powerfully on how well we understand this Cosmos in which we float like a mote of dust in the morning sky.

Carl Sagan
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
The so-called generation gap is a consequence of the rate of social and technological change. Even within a human lifetime, the change is so great that many people are alienated from their own society. Margaret Mead had described older people as involuntary immigrants from the past to the present.

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
[Science is not popular] is... the fault of the educational system. We do not teach how to think. This is a very serious failure that may even, in a world rigged with 60,000 nuclear weapons, compromise the human future.

Carl Sagan
Science is a way of thinking much more than it is a body of knowledge. Its goal is to find out how the world works, to seek what regularities there may be, to penetrate to the connections of things-from subatomic particles, which may be the constituents of all matter, to living organisms, the human social community, and thence to the cosmos as a whole.

Carl Sagan
Some racists still reject the plain testimony written in the DNA that all the races are not only human but nearly indistinguishable....

Carl Sagan
Suppose your father... walked into this room at the ordinary human pace of walking. And suppose just behind him was his father. How long would we have to wait before the ancestor who enters the now-open door is a creature who normally walked on all fours? The answer is a week.

Carl Sagan
The Apollo pictures of the whole Earth conveyed to multitudes something well known to astronomers: On the scale of the worlds - to say nothing of stars or galaxies - humans are inconsequential, a thin film of life on an obscure and solitary lump of rock and metal

Carl Sagan
Our intelligence and our technology have given us the power to affect the climate. How will we use this power? Are we willing to tolerate ignorance and complacency in matters that affect the entire human family? Do we value short-term advantages above the welfare of the Earth? Or will we think on longer time scales, with concern for our children and our grandchildren, to understand and protect the complex life-support systems of our planet? The Earth is a tiny and fragile world. It needs to be cherished.

Carl Sagan
Human history can be viewed as a slowly dawning awareness that we are members of a larger group.

Carl Sagan
Writing is perhaps the greatest of human inventions, binding together people, citizens of distant epochs, who never knew one another. Books break the shackles of time, proof that humans can work magic.

Carl Sagan
Football is a thinly disguised re-enactment of hunting; we played it before we were human.

Carl Sagan
Your religion assumes that people are children and need a boogeyman so they'll behave. You want people to believe in God so they'll obey the law. That's the only means that occurs to you: a strict secular police force, and the threat of punishment by an all-seeing God for whatever the police overlook. You sell human beings short.

Carl Sagan
Books permit us to voyage through time, to tap the wisdom of our ancestors. The library connects us with the insights and knowledge, painfully extracted from Nature, of the greatest minds that ever were, with the best teachers, drawn from the entire planet and from all of our history, to instruct us without tiring, and to inspire us to make our own contribution to the collective knowledge of the human species. Public libraries depend on voluntary contributions. I think the health of our civilization, the depth of our awareness about the underpinnings of our culture and our concern for the future can all be tested by how well we support our libraries.

Carl Sagan
For a long time the human instinct to understand was thwarted by facile religious explanations.

Carl Sagan
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.

Carl Sagan
Avoidable human misery is more often caused not so much by stupidity as by ignorance, particularly our ignorance about ourselves.

Carl Sagan
Think of how many religions attempt to validate themselves with prophecy. Think of how many people rely on these prophecies, however vague, however unfulfilled, to support or prop up their beliefs. Yet has there ever been a religion with the prophetic accuracy and reliability of science? … No other human institution comes close.

Carl Sagan
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.

Carl Sagan
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.

Carl Sagan
For as long as there been humans we have searched for our place in the cosmos. Where are we? Who are we? We find that we live on an insignificant planet of a hum-drum star lost in a galaxy tucked away in some forgotten corner of a universe in which there are far more galaxies than people. This perspective is a courageous continuation of our penchant for constructing and testing mental models of the skies; the Sun as a red-hot stone, the stars as a celestial flame, the Galaxy as the backbone of night.

Carl Sagan
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?

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

Carl Sagan