Cosmos by Carl Sagan (Quotes and Excerpts)

Thought-provoking quotes and excerpts from the highly influential non-fiction science book/tv-series Cosmos by Carl Sagan.

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Carl Sagan Quote: The beauty of a living thing is not the atoms that go into it, but the way those atoms are put together.
The beauty of a living thing is not the atoms that go into it, but the way those atoms are put together.
Carl Sagan
Atoms are mainly empty space. Matter is composed chiefly of nothing.
Carl Sagan
If you wish to make an apple pie from scratch, you must first invent the universe.
Carl Sagan
Carl Sagan Quote: We are like butterflies who flutter for a day and think it is forever.
We are like butterflies who flutter for a day and think it is forever.
Carl Sagan
We are a way for the cosmos to know itself.
Carl Sagan
If we ruin the earth, there is no place else to go.
Carl Sagan
Carl Sagan Quote: Books are like seeds. They can lie dormant for centuries and then flower in the most unpromising soil.
Books are like seeds. They can lie dormant for centuries and then flower in the most unpromising soil.
Carl Sagan
Books permit us to voyage through time, to tap the wisdom of our ancestors.
Carl Sagan
If I finish a book a week, I will read only a few thousand books in my lifetime, about a tenth of a percent of the contents of the greatest libraries of our time. The trick is to know which books to read.
Carl Sagan
Carl Sagan Quote: We must understand the Cosmos as it is and not confuse how it is with how we wish it to be.
We must understand the Cosmos as it is and not confuse how it is with how we wish it to be.
Carl Sagan
Meanwhile the Cosmos is rich beyond measure: the total number of stars in the universe is greater than all the grains of sand on all the beaches of the planet Earth.
Carl Sagan
Carl Sagan Quote: Cosmos is a Greek word for the order of the universe. It is, in a way, the opposite of Chaos. It implies the deep interconnectedness of all things. It conveys awe for the intricate and subtle way in which the universe is put together.
Cosmos is a Greek word for the order of the universe. It is, in a way, the opposite of Chaos. It implies the deep interconnectedness of all things. It conveys awe for the intricate and subtle way in which the universe is put together.
Carl Sagan
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 Quote: Science is an ongoing process. It never ends. There is no single ultimate truth to be achieved, after which all the scientists can retire.
Science is an ongoing process. It never ends. There is no single ultimate truth to be achieved, after which all the scientists can retire.
Carl Sagan
Science needs the light of free expression to flourish. It depends on the fearless questioning of authority, and the open exchange of ideas.
Carl Sagan
There are many hypotheses in science that are wrong. That's perfectly alright; it's the aperture to finding out what's right. Science is a self-correcting process. To be accepted, new ideas must survive the most rigorous standards of evidence and scrutiny.
Carl Sagan
Carl Sagan Quote: Exploration is in our nature. We began as wanderers, and we are wanderers still. We have lingered long enough on the shores of the cosmic ocean. We are ready at last to set sail for the stars.
Exploration is in our nature. We began as wanderers, and we are wanderers still. We have lingered long enough on the shores of the cosmic ocean. We are ready at last to set sail for the stars.
Carl Sagan
Civilization is a product of the cerebral cortex.
Carl Sagan
If we long for our planet to be important, there is something we can do about it. We make our world significant by the courage of our questions and by the depth of our answers.
Carl Sagan
The nitrogen in our DNA, the calcium in our teeth, the iron in our blood, the carbon in our apple pies were made in the interiors of collapsing stars. We are made of starstuff.
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
A galaxy is composed of gas and dust and stars - billions upon billions of stars. Every star may be a sun to someone.
Carl Sagan
By looking far out into space we are also looking far back into time, back toward the horizon of the universe, back toward the epoch of the Big Bang.
Carl Sagan
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.
Carl Sagan
For the first time, we have the power to decide the fate of our planet and ourselves. This is a time of great danger, but our species is young, and curious, and brave. It shows much promise.
Carl Sagan
The Greek religion explained that diffuse band of light in the night sky as the milk of Hera, squirted from her breast across the heavens, a legend that is the origin of the phrase Westerners still use—the Milky Way.
Carl Sagan
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.
Carl Sagan
National boundaries are not evident when we view the Earth from space. Fanatical ethnic or religious or national chauvinisms are a little difficult to maintain when we see our planet as a fragile blue crescent fading to become an inconspicuous point of light against the bastion and citadel of the stars.
Carl Sagan
The study of the galaxies reveals a universal order and beauty. It also shows us chaotic violence on a scale hitherto undreamed of. That we live in a universe which permits life is remarkable. That we live in one which destroys galaxies and stars and worlds is also remarkable. The universe seems neither benign nor hostile, merely indifferent to the concerns of such puny creatures as we.
Carl Sagan
We on Earth have just awakened to the great oceans of space and time from which we have emerged. We are the legacy of 15 billion years of cosmic evolution. We have a choice: We can enhance life and come to know the universe that made us, or we can squander our 15 billion-year heritage in meaningless self-destruction. What happens in the first second of the next cosmic year depends on what we do, here and now, with our intelligence and our knowledge of the cosmos.
Carl Sagan
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.
Carl Sagan
Every aspect of Nature reveals a deep mystery and touches our sense of wonder and awe. Those afraid of the universe as it really is, those who pretend to nonexistent knowledge and envision a Cosmos centered on human beings will prefer the fleeting comforts of superstition. They avoid rather than confront the world. But those with the courage to explore the weave and structure of the Cosmos, even where it differs profoundly from their wishes and prejudices, will penetrate its deepest mysteries.
Carl Sagan
What an astonishing thing a book is. It's a flat object made from a tree with flexible parts on which are imprinted lots of funny dark squiggles. But one glance at it and you're inside the mind of another person, maybe somebody dead for thousands of years. Across the millennia, an author is speaking clearly and silently inside your head, directly to you. Writing is perhaps the greatest of human inventions, binding together people who never knew each other, citizens of distant epochs. Books break the shackles of time. A book is proof that humans are capable of working magic.
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 on how well we know this Cosmos in which we float like a mote of dust in the morning sky.
Carl Sagan
All my life I have wondered about the possibility of life elsewhere. What would it be like? Of what would it be made? All living things on our planet are constructed of organic molecules—complex microscopic architectures in which the carbon atom plays a central role. There was once a time before life, when the Earth was barren and utterly desolate. Our world is now overflowing with life. How did it come about? How, in the absence of life, were carbon-based organic molecules made? How did the first living things arise? How did life evolve to produce beings as elaborate and complex as we, able to explore the mystery of our own origins? And on the countless other planets that may circle other suns, is there life also? Is extraterrestrial life, if it exists, based on the same organic molecules as life on Earth? Do the beings of other worlds look much like life on Earth? Or are they stunningly different—other adaptations to other environments? What else is possible? The nature of life on Earth and the search for life elsewhere are two sides of the same question—the search for who we are. In the great dark between the stars there are clouds of gas and dust and organic matter. Dozens of different kinds of organic molecules have been found there by radio telescopes. The abundance of these molecules suggests that the stuff of life is everywhere. Perhaps the origin and evolution of life is, given enough time, a cosmic inevitability. On some of the billions of planets in the Milky Way Galaxy, life may never arise. On others, it may arise and die out, or never evolve beyond its simplest forms. And on some small fraction of worlds there may develop intelligences and civilizations more advanced than our own. Occasionally someone remarks on what a lucky coincidence it is that the Earth is perfectly suitable for life—moderate temperatures, liquid water, oxygen atmosphere, and so on. But this is, at least in part, a confusion of cause and effect. We earthlings are supremely well adapted to the environment of the Earth because we grew up here. Those earlier forms of life that were not well adapted died. We are descended from the organisms that did well. Organisms that evolve on a quite different world will doubtless sing its praises too. All life on Earth is closely related. We have a common organic chemistry and a common evolutionary heritage. As a result, our biologists are profoundly limited. They study only a single kind of biology, one lonely theme in the music of life. Is this faint and reedy tune the only voice for thousands of light-years? Or is there a kind of cosmic fugue, with themes and counterpoints, dissonances and harmonies, a billion different voices playing the life music of the Galaxy?
Carl Sagan

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Cosmos Info

Published: 1980

Cosmos is a popular science book written by the astrophysicist and author Carl Sagan.

The book dives deep into the history and nature of the universe that we're living in.

Read the whole book