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Carl Sagan

Scientist

Carl Sagan was a renowned astrophysicist, cosmologist, and science communicator whose work sparked curiosity and wonder about the universe. Known for his ability to make complex scientific ideas accessible, his words often reflect a deep sense of awe for the cosmos and the importance of critical thinking and exploration. The following quotes capture his vision of science, humanity’s place in the universe, and the endless possibilities for discovery.

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Science is not only compatible with spirituality; it is a profound source of spirituality.
From The Demon-Haunted World: Science as a Candle in the Dark
NOT YET RATING
I don't want to believe. I want to know.
NOT YET RATING
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.
From Contact
NOT YET RATING
Topic: Religion
If we are merely matter intricately assembled, is this really demeaning? If there's nothing here but atoms, does that make us less or does that make matter more?
From The Varieties of Scientific Experience: A Personal View of the Search for God
NOT YET RATING
The visions we offer our children shape the future. It _matters_ what those visions are. Often they become self-fulfilling prophecies. Dreams are maps.
From Pale Blue Dot: A Vision of the Human Future in Space
NOT YET RATING
Topic: Hope
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.
From Cosmos
NOT YET RATING
Topic: Life
But, Jefferson worried that the people - and the argument goes back to Thucydides and Aristotle - are easily misled. He also stressed, passionately and repeatedly, that it was essential for the people to understand the risks and benefits of government, to educate themselves, and to involve themselves in the political process.

Without that, he said, the wolves will take over.
From The Demon-Haunted World: Science as a Candle in the Dark
NOT YET RATING
Topic: Education
The significance of our lives and our fragile planet is then determined only by our own wisdom and courage. We are the custodians of life's meaning. We long for a Parent to care for us, to forgive us our errors, to save us from our childish mistakes. But knowledge is preferable to ignorance. Better by far to embrace the hard truth than a reassuring fable. If we crave some cosmic purpose, then let us find ourselves a worthy goal.
From Pale Blue Dot: A Vision of the Human Future in Space
NOT YET RATING
Topic: Religion
But 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.
From Broca's Brain: Reflections on the Romance of Science
NOT YET RATING
I do not think it irresponsible to portray even the direst futures if we are to avoid them we must understand that they are possible. But where are the alternatives Where are the dreams that motivate and inspire We long for realistic maps of a world we can be proud to give to our children. Where are the cartographers of human purpose Where are the visions of hopeful futures of technology as a tool for human betterment and not a gun on hair trigger pointed at our heads
From Pale Blue Dot: A Vision of the Human Future in Space
NOT YET RATING
Topic: Hope
When I wake up I go through an abbreviated process of mourning all over again. Plainly, there’s something within me that’s ready to believe in life after death. And it’s not the least bit interested in whether there’s any sober evidence for it.
From The Demon-Haunted World: Science as a Candle in the Dark
NOT YET RATING
Topic: Death, Religion
Books permit us to voyage through time, to tap the wisdom of our ancestors. The library connects us with the insight 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 our history, to instruct us without tiring, and to inspire us to make our own contribution to the collective knowledge of the human species. 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.
From Cosmos
NOT YET RATING
Topic: Education
The world is so exquisite with so much love and moral depth, that there is no reason to deceive ourselves with pretty stories for which there's little good evidence. Far better it seems to me, in our vulnerability, is to look death in the eye and to be grateful every day for the brief but magnificent opportunity that life provides.
NOT YET RATING
Topic: Religion
The fossil record implies trial and error, the inability to anticipate the future, features inconsistent with a Great Designer (though not a Designer of a more remote and indirect temperament.)
From Cosmos
NOT YET RATING
Nevertheless, (Jefferson) believed that the habit of skepticism is an essential prerequisite for responsible citizenship. He argued that the cost of education is trivial compared to the cost of ignorance, of leaving government to the wolves. He taught that the country is safe only when the people rule.
From The Demon-Haunted World: Science as a Candle in the Dark
NOT YET RATING
Topic: Education
Their position seems to be that their God is so great he doesn't even have to exist.
From Contact
NOT YET RATING
Topic: Religion
A new concept of god: “something not very different from the sum total of the physical laws of the universe; that is, gravitation plus quantum mechanics plus grand unified field theories plus a few other things equaled god. And by that all they meant was that here were a set of exquisitely powerful physical principles that seemed to explain a great deal that was otherwise inexplicable about the universe. Laws of nature…that apply not just locally, not just in Glasgow, but far beyond: Edinburgh, Moscow…Mars…the center of the Milky Way, and out by the most distant quarters known. That the same laws of physics apply everywhere is quite remarkable. Certainly that represents a power greater than any of us.
From The Varieties of Scientific Experience: A Personal View of the Search for God
NOT YET RATING
Topic: Religion
The beauty of a living thing is not the atoms that go into it, but the way those atoms are put together.
From Cosmos
NOT YET RATING
For small creatures such as we the vastness is bearable only through love.
NOT YET RATING
Topic: Life
All over the world there are enormous numbers of smart, even gifted, people who harbor a passion for science. But that passion is unrequited. Surveys suggest that some 95 percent of Americans are “scientifically illiterate.” That’s just the same fraction as those African Americans, almost all of them slaves, who were illiterate just before the Civil War—when severe penalties were in force for anyone who taught a slave to read. Of course there’s a degree of arbitrariness about any determination of illiteracy, whether it applies to language or to science. But anything like 95 percent illiteracy is extremely serious.
From The Demon-Haunted World: Science as a Candle in the Dark
NOT YET RATING
Topic: Education
Those at too great a distance may, I am well are, mistake ignorance for perspective.
From The Dragons of Eden: Speculations on the Evolution of Human Intelligence
NOT YET RATING
Topic: Education
There is much that science doesn't understand, many mysteries still to be resolved. In a Universe tens of billions of light-years across and some ten or fifteen billion years old, this may be the case forever. We are constantly stumbling on new surprises
From The Demon-Haunted World: Science as a Candle in the Dark
NOT YET RATING
Topic: Education
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.
NOT YET RATING
Topic: Religion
Science is not only compatible with spirituality; it is a profound source of spirituality. When we recognize our place in an immensity of light‐years and in the passage of ages, when we grasp the intricacy, beauty, and subtlety of life, then that soaring feeling, that sense of elation and humility combined, is surely spiritual. So are our emotions in the presence of great art or music or literature, or acts of exemplary selfless courage such as those of Mohandas Gandhi or Martin Luther King, Jr. The notion that science and spirituality are somehow mutually exclusive does a disservice to both.
From The Demon-Haunted World: Science as a Candle in the Dark
NOT YET RATING
Topic: Religion
Science is not only compatible with spirituality; it is a profound source of spirituality.
From The Demon-Haunted World: Science as a Candle in the Dark
NOT YET RATING
I don't want to believe. I want to know.
NOT YET RATING
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.
From Contact
NOT YET RATING
Topic: Religion
If we are merely matter intricately assembled, is this really demeaning? If there's nothing here but atoms, does that make us less or does that make matter more?
From The Varieties of Scientific Experience: A Personal View of the Search for God
NOT YET RATING
The visions we offer our children shape the future. It _matters_ what those visions are. Often they become self-fulfilling prophecies. Dreams are maps.
From Pale Blue Dot: A Vision of the Human Future in Space
NOT YET RATING
Topic: Hope
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.
From Cosmos
NOT YET RATING
Topic: Life
But, Jefferson worried that the people - and the argument goes back to Thucydides and Aristotle - are easily misled. He also stressed, passionately and repeatedly, that it was essential for the people to understand the risks and benefits of government, to educate themselves, and to involve themselves in the political process.

Without that, he said, the wolves will take over.
From The Demon-Haunted World: Science as a Candle in the Dark
NOT YET RATING
Topic: Education
The significance of our lives and our fragile planet is then determined only by our own wisdom and courage. We are the custodians of life's meaning. We long for a Parent to care for us, to forgive us our errors, to save us from our childish mistakes. But knowledge is preferable to ignorance. Better by far to embrace the hard truth than a reassuring fable. If we crave some cosmic purpose, then let us find ourselves a worthy goal.
From Pale Blue Dot: A Vision of the Human Future in Space
NOT YET RATING
Topic: Religion
But 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.
From Broca's Brain: Reflections on the Romance of Science
NOT YET RATING
I do not think it irresponsible to portray even the direst futures if we are to avoid them we must understand that they are possible. But where are the alternatives Where are the dreams that motivate and inspire We long for realistic maps of a world we can be proud to give to our children. Where are the cartographers of human purpose Where are the visions of hopeful futures of technology as a tool for human betterment and not a gun on hair trigger pointed at our heads
From Pale Blue Dot: A Vision of the Human Future in Space
NOT YET RATING
Topic: Hope
When I wake up I go through an abbreviated process of mourning all over again. Plainly, there’s something within me that’s ready to believe in life after death. And it’s not the least bit interested in whether there’s any sober evidence for it.
From The Demon-Haunted World: Science as a Candle in the Dark
NOT YET RATING
Topic: Death, Religion
Books permit us to voyage through time, to tap the wisdom of our ancestors. The library connects us with the insight 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 our history, to instruct us without tiring, and to inspire us to make our own contribution to the collective knowledge of the human species. 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.
From Cosmos
NOT YET RATING
Topic: Education
The world is so exquisite with so much love and moral depth, that there is no reason to deceive ourselves with pretty stories for which there's little good evidence. Far better it seems to me, in our vulnerability, is to look death in the eye and to be grateful every day for the brief but magnificent opportunity that life provides.
NOT YET RATING
Topic: Religion
The fossil record implies trial and error, the inability to anticipate the future, features inconsistent with a Great Designer (though not a Designer of a more remote and indirect temperament.)
From Cosmos
NOT YET RATING
Nevertheless, (Jefferson) believed that the habit of skepticism is an essential prerequisite for responsible citizenship. He argued that the cost of education is trivial compared to the cost of ignorance, of leaving government to the wolves. He taught that the country is safe only when the people rule.
From The Demon-Haunted World: Science as a Candle in the Dark
NOT YET RATING
Topic: Education
Their position seems to be that their God is so great he doesn't even have to exist.
From Contact
NOT YET RATING
Topic: Religion
A new concept of god: “something not very different from the sum total of the physical laws of the universe; that is, gravitation plus quantum mechanics plus grand unified field theories plus a few other things equaled god. And by that all they meant was that here were a set of exquisitely powerful physical principles that seemed to explain a great deal that was otherwise inexplicable about the universe. Laws of nature…that apply not just locally, not just in Glasgow, but far beyond: Edinburgh, Moscow…Mars…the center of the Milky Way, and out by the most distant quarters known. That the same laws of physics apply everywhere is quite remarkable. Certainly that represents a power greater than any of us.
From The Varieties of Scientific Experience: A Personal View of the Search for God
NOT YET RATING
Topic: Religion
The beauty of a living thing is not the atoms that go into it, but the way those atoms are put together.
From Cosmos
NOT YET RATING
For small creatures such as we the vastness is bearable only through love.
NOT YET RATING
Topic: Life
All over the world there are enormous numbers of smart, even gifted, people who harbor a passion for science. But that passion is unrequited. Surveys suggest that some 95 percent of Americans are “scientifically illiterate.” That’s just the same fraction as those African Americans, almost all of them slaves, who were illiterate just before the Civil War—when severe penalties were in force for anyone who taught a slave to read. Of course there’s a degree of arbitrariness about any determination of illiteracy, whether it applies to language or to science. But anything like 95 percent illiteracy is extremely serious.
From The Demon-Haunted World: Science as a Candle in the Dark
NOT YET RATING
Topic: Education
Those at too great a distance may, I am well are, mistake ignorance for perspective.
From The Dragons of Eden: Speculations on the Evolution of Human Intelligence
NOT YET RATING
Topic: Education
There is much that science doesn't understand, many mysteries still to be resolved. In a Universe tens of billions of light-years across and some ten or fifteen billion years old, this may be the case forever. We are constantly stumbling on new surprises
From The Demon-Haunted World: Science as a Candle in the Dark
NOT YET RATING
Topic: Education
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.
NOT YET RATING
Topic: Religion
Science is not only compatible with spirituality; it is a profound source of spirituality. When we recognize our place in an immensity of light‐years and in the passage of ages, when we grasp the intricacy, beauty, and subtlety of life, then that soaring feeling, that sense of elation and humility combined, is surely spiritual. So are our emotions in the presence of great art or music or literature, or acts of exemplary selfless courage such as those of Mohandas Gandhi or Martin Luther King, Jr. The notion that science and spirituality are somehow mutually exclusive does a disservice to both.
From The Demon-Haunted World: Science as a Candle in the Dark
NOT YET RATING
Topic: Religion
Science is not only compatible with spirituality; it is a profound source of spirituality.
From The Demon-Haunted World: Science as a Candle in the Dark
NOT YET RATING
I don't want to believe. I want to know.
NOT YET RATING
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.
From Contact
NOT YET RATING
Topic: Religion
If we are merely matter intricately assembled, is this really demeaning? If there's nothing here but atoms, does that make us less or does that make matter more?
From The Varieties of Scientific Experience: A Personal View of the Search for God
NOT YET RATING
The visions we offer our children shape the future. It _matters_ what those visions are. Often they become self-fulfilling prophecies. Dreams are maps.
From Pale Blue Dot: A Vision of the Human Future in Space
NOT YET RATING
Topic: Hope
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.
From Cosmos
NOT YET RATING
Topic: Life
But, Jefferson worried that the people - and the argument goes back to Thucydides and Aristotle - are easily misled. He also stressed, passionately and repeatedly, that it was essential for the people to understand the risks and benefits of government, to educate themselves, and to involve themselves in the political process.

Without that, he said, the wolves will take over.
From The Demon-Haunted World: Science as a Candle in the Dark
NOT YET RATING
Topic: Education
The significance of our lives and our fragile planet is then determined only by our own wisdom and courage. We are the custodians of life's meaning. We long for a Parent to care for us, to forgive us our errors, to save us from our childish mistakes. But knowledge is preferable to ignorance. Better by far to embrace the hard truth than a reassuring fable. If we crave some cosmic purpose, then let us find ourselves a worthy goal.
From Pale Blue Dot: A Vision of the Human Future in Space
NOT YET RATING
Topic: Religion
But 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.
From Broca's Brain: Reflections on the Romance of Science
NOT YET RATING
I do not think it irresponsible to portray even the direst futures if we are to avoid them we must understand that they are possible. But where are the alternatives Where are the dreams that motivate and inspire We long for realistic maps of a world we can be proud to give to our children. Where are the cartographers of human purpose Where are the visions of hopeful futures of technology as a tool for human betterment and not a gun on hair trigger pointed at our heads
From Pale Blue Dot: A Vision of the Human Future in Space
NOT YET RATING
Topic: Hope
When I wake up I go through an abbreviated process of mourning all over again. Plainly, there’s something within me that’s ready to believe in life after death. And it’s not the least bit interested in whether there’s any sober evidence for it.
From The Demon-Haunted World: Science as a Candle in the Dark
NOT YET RATING
Topic: Death, Religion
Books permit us to voyage through time, to tap the wisdom of our ancestors. The library connects us with the insight 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 our history, to instruct us without tiring, and to inspire us to make our own contribution to the collective knowledge of the human species. 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.
From Cosmos
NOT YET RATING
Topic: Education
The world is so exquisite with so much love and moral depth, that there is no reason to deceive ourselves with pretty stories for which there's little good evidence. Far better it seems to me, in our vulnerability, is to look death in the eye and to be grateful every day for the brief but magnificent opportunity that life provides.
NOT YET RATING
Topic: Religion
The fossil record implies trial and error, the inability to anticipate the future, features inconsistent with a Great Designer (though not a Designer of a more remote and indirect temperament.)
From Cosmos
NOT YET RATING
Nevertheless, (Jefferson) believed that the habit of skepticism is an essential prerequisite for responsible citizenship. He argued that the cost of education is trivial compared to the cost of ignorance, of leaving government to the wolves. He taught that the country is safe only when the people rule.
From The Demon-Haunted World: Science as a Candle in the Dark
NOT YET RATING
Topic: Education
Their position seems to be that their God is so great he doesn't even have to exist.
From Contact
NOT YET RATING
Topic: Religion
A new concept of god: “something not very different from the sum total of the physical laws of the universe; that is, gravitation plus quantum mechanics plus grand unified field theories plus a few other things equaled god. And by that all they meant was that here were a set of exquisitely powerful physical principles that seemed to explain a great deal that was otherwise inexplicable about the universe. Laws of nature…that apply not just locally, not just in Glasgow, but far beyond: Edinburgh, Moscow…Mars…the center of the Milky Way, and out by the most distant quarters known. That the same laws of physics apply everywhere is quite remarkable. Certainly that represents a power greater than any of us.
From The Varieties of Scientific Experience: A Personal View of the Search for God
NOT YET RATING
Topic: Religion
The beauty of a living thing is not the atoms that go into it, but the way those atoms are put together.
From Cosmos
NOT YET RATING
For small creatures such as we the vastness is bearable only through love.
NOT YET RATING
Topic: Life
All over the world there are enormous numbers of smart, even gifted, people who harbor a passion for science. But that passion is unrequited. Surveys suggest that some 95 percent of Americans are “scientifically illiterate.” That’s just the same fraction as those African Americans, almost all of them slaves, who were illiterate just before the Civil War—when severe penalties were in force for anyone who taught a slave to read. Of course there’s a degree of arbitrariness about any determination of illiteracy, whether it applies to language or to science. But anything like 95 percent illiteracy is extremely serious.
From The Demon-Haunted World: Science as a Candle in the Dark
NOT YET RATING
Topic: Education
Those at too great a distance may, I am well are, mistake ignorance for perspective.
From The Dragons of Eden: Speculations on the Evolution of Human Intelligence
NOT YET RATING
Topic: Education
There is much that science doesn't understand, many mysteries still to be resolved. In a Universe tens of billions of light-years across and some ten or fifteen billion years old, this may be the case forever. We are constantly stumbling on new surprises
From The Demon-Haunted World: Science as a Candle in the Dark
NOT YET RATING
Topic: Education
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.
NOT YET RATING
Topic: Religion
Science is not only compatible with spirituality; it is a profound source of spirituality. When we recognize our place in an immensity of light‐years and in the passage of ages, when we grasp the intricacy, beauty, and subtlety of life, then that soaring feeling, that sense of elation and humility combined, is surely spiritual. So are our emotions in the presence of great art or music or literature, or acts of exemplary selfless courage such as those of Mohandas Gandhi or Martin Luther King, Jr. The notion that science and spirituality are somehow mutually exclusive does a disservice to both.
From The Demon-Haunted World: Science as a Candle in the Dark
NOT YET RATING
Topic: Religion
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