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Home > Dictionary of Science Quotations > Scientist Names Index S > Carl Sagan Quotes > Life

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Carl Sagan
(9 Nov 1934 - 20 Dec 1996)

American astronomer, exobiologist and writer remembered for popularizing astronomy and science, especially with his public television series Cosmos. Its accompanying book spent seventy weeks on The New York Times bestseller list. He was an adviser to NASA for the Mariner, Voyager, and Viking unmanned space missions.



Carl Sagan quote Advances in medicine and agriculture
A bean farmer checks her crop in Congo. Photo by Neil Palmer (CIAT). CC2.0 (source)
Advances in medicine and agriculture have saved vastly more lives than have been lost in all the wars in history.
— Carl Sagan
The Demon-Haunted World: Science as a Candle in the Dark (1996), 11.
Science quotes on:  |  Agriculture (66)  |  History (369)  |  Life (1131)  |  Medicine (344)  |  Progress (368)  |  War (161)

Comets giveth and comets taketh away.
— Carl Sagan
In Comet (1885, 1997), 337. [Note the context refers to the idea that although perhaps comets seeded life on earth, later comet collisions with Earth could cause mass extinctions.]
Science quotes on:  |  Comet (50)  |  Extinction (66)  |  Give (201)  |  Life (1131)  |  Take (10)

I grew up in Brooklyn, New York … a city neighborhood that included houses, lampposts, walls, and bushes. But with an early bedtime in the winter, I could look out my window and see the stars, and the stars were not like anything else in my neighborhood. [At age 5] I didn’t know what they were.
[At age 9] my mother … said to me, “You have a library card now, and you know how to read. Take the streetcar to the library and get a book on stars.” … I stepped up to the big librarian and asked for a book on stars. … I sat down and found out the answer, which was something really stunning.
I found out that the stars are glowing balls of gas. I also found out that the Sun is a star but really close and that the stars are all suns except really far away I didn’t know any physics or mathematics at that time, but I could imagine how far you’d have to move the Sun away from us till it was only as bright as a star. It was in that library, reading that book, that the scale of the universe opened up to me. There was something beautiful about it.
At that young age, I already knew that I’d be very happy if I could devote my life to finding out more about the stars and the planets that go around them. And it’s been my great good fortune to do just that.
— Carl Sagan
Quoted in interview with Jack Rightmyer, in 'Stars in His Eyes', Highlights For Children (1 Jan 1997). Ages as given in Tom Head (ed.), Conversations with Carl Sagan (2006), x.
Science quotes on:  |  Answer (249)  |  Beauty (248)  |  Biography (232)  |  Brooklyn (3)  |  Career (57)  |  Child (253)  |  Happiness (94)  |  Library (40)  |  Scale (63)  |  Star (336)  |  Sun (277)  |  Universe (686)  |  Window (40)

If we lived on a planet where nothing ever changed, there would be little to do. There would be nothing to figure out. There would be no impetus for science. And if we lived in an unpredictable world, where things changed in random or very complex ways, we would not be able to figure things out. But we live in an in-between universe, where things change, but according to patterns, rules, or as we call them, laws of nature. If I throw a stick up in the air, it always falls down. If the sun sets in the west, it always rises again the next morning in the east. And so it becomes possible to figure things out. We can do science, and with it we can improve our lives.
— Carl Sagan
Cosmos (1980, 1985), 32.
Science quotes on:  |  Ability (108)  |  Change (364)  |  Complexity (91)  |  Doing (36)  |  Down (86)  |  East (18)  |  Fall (120)  |  Figure Out (6)  |  Impetus (3)  |  Improvement (74)  |  Law Of Nature (64)  |  Life (1131)  |  Little (188)  |  Morning (44)  |  Nothing (396)  |  Pattern (79)  |  Planet (263)  |  Random (25)  |  Rise (70)  |  Rule (177)  |  Science (2067)  |  Setting (6)  |  Stick (24)  |  Sun (277)  |  Throw (43)  |  Universe (686)  |  Unpredictability (7)  |  West (17)  |  World (898)

In fact, the thickness of the Earth's atmosphere, compared with the size of the Earth, is in about the same ratio as the thickness of a coat of shellac on a schoolroom globe is to the diameter of the globe. That's the air that nurtures us and almost all other life on Earth, that protects us from deadly ultraviolet light from the sun, that through the greenhouse effect brings the surface temperature above the freezing point. (Without the greenhouse effect, the entire Earth would plunge below the freezing point of water and we'd all be dead.) Now that atmosphere, so thin and fragile, is under assault by our technology. We are pumping all kinds of stuff into it. You know about the concern that chlorofluorocarbons are depleting the ozone layer; and that carbon dioxide and methane and other greenhouse gases are producing global warming, a steady trend amidst fluctuations produced by volcanic eruptions and other sources. Who knows what other challenges we are posing to this vulnerable layer of air that we haven't been wise enough to foresee?
— Carl Sagan
In 'Wonder and Skepticism', Skeptical Enquirer (Jan-Feb 1995), 19, No. 1.
Science quotes on:  |  Air (190)  |  Assault (11)  |  Atmosphere (79)  |  Carbon Dioxide (20)  |  Challenge (61)  |  Concern (110)  |  Death (302)  |  Diameter (10)  |  Earth (638)  |  Eruption (7)  |  Freezing Point (2)  |  Global Warming (26)  |  Globe (47)  |  Greenhouse Effect (4)  |  Greenhouse Gas (3)  |  Layer (22)  |  Life (1131)  |  Light (348)  |  Methane (7)  |  Nurture (16)  |  Ozone (3)  |  Pump (6)  |  Ratio (19)  |  School (119)  |  Source (91)  |  Stuff (21)  |  Sun (277)  |  Surface (101)  |  Technology (222)  |  Temperature (47)  |  Thickness (5)  |  Thin (16)  |  Trend (17)  |  Ultraviolet (2)  |  Volcano (39)  |  Vulnerability (5)  |  Water (294)  |  Wisdom (182)

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 ... The notion that science and spirituality are somehow mutually exclusive does a disservice to both.
— Carl Sagan
In Demon-Haunted World: Science as a Candle in the Dark (1995), 29.
Science quotes on:  |  Age (180)  |  Beauty (248)  |  Compatible (4)  |  Disservice (4)  |  Elation (2)  |  Exclusive (16)  |  Feeling (91)  |  Grasp (60)  |  Humility (23)  |  Immensity (21)  |  Intricacy (7)  |  Life (1131)  |  Mutually (7)  |  Notion (59)  |  Passage (20)  |  Place (175)  |  Profound (59)  |  Recognize (69)  |  Science And Religion (302)  |  Sense (321)  |  Soaring (3)  |  Source (91)  |  Spiritual (57)  |  Spirituality (8)  |  Subtlety (11)  |  Surely (13)

The secrets of evolution are death and time—the deaths of enormous numbers of lifeforms that were imperfectly adapted to the environment; and time for a long succession of small mutations.
— Carl Sagan
Cosmos (1980, 1985), 20.
Science quotes on:  |  Adaptation (49)  |  Death (302)  |  Environment (181)  |  Evolution (535)  |  Extinction (66)  |  Lifeform (2)  |  Mutation (30)  |  Secret (131)  |  Succession (45)  |  Time (596)


See also:
  • 9 Nov - short biography, births, deaths and events on date of Sagan's birth.
  • Carl Sagan - context of quote A Subject Called Chemistry - Medium image (500 x 350 px)
  • Carl Sagan - context of quote A Subject Called Chemistry - Large image (800 x 600 px)
  • Carl Sagan - context of quote “Advances in medicine and agriculture” - Medium image (500 x 250 px)
  • Carl Sagan - context of quote “Advances in medicine and agriculture” - Large image (800 x 400 px)
  • Carl Sagan: A Life in the Cosmos, by William Poundstone. - book suggestion.
  • Booklist for Carl Sagan.

Carl Sagan Thumbnail 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. (1987) -- Carl Sagan
Quotations by: • Albert Einstein • Isaac Newton • Lord Kelvin • Charles Darwin • Srinivasa Ramanujan • Carl Sagan • Florence Nightingale • Thomas Edison • Aristotle • Marie Curie • Benjamin Franklin • Winston Churchill • Galileo Galilei • Sigmund Freud • Robert Bunsen • Louis Pasteur • Theodore Roosevelt • Abraham Lincoln • Ronald Reagan • Leonardo DaVinci • Michio Kaku • Karl Popper • Johann Goethe • Robert Oppenheimer • Charles Kettering  ... (more people)

Quotations about: • Atomic  Bomb • Biology • Chemistry • Deforestation • Engineering • Anatomy • Astronomy • Bacteria • Biochemistry • Botany • Conservation • Dinosaur • Environment • Fractal • Genetics • Geology • History of Science • Invention • Jupiter • Knowledge • Love • Mathematics • Measurement • Medicine • Natural Resource • Organic Chemistry • Physics • Physician • Quantum Theory • Research • Science and Art • Teacher • Technology • Universe • Volcano • Virus • Wind Power • Women Scientists • X-Rays • Youth • Zoology  ... (more topics)
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Sophie Germain
Gertrude Elion
Ernest Rutherford
James Chadwick
Marcel Proust
William Harvey
Johann Goethe
John Keynes
Carl Gauss
Paul Feyerabend
- 90 -
Antoine Lavoisier
Lise Meitner
Charles Babbage
Ibn Khaldun
Euclid
Ralph Emerson
Robert Bunsen
Frederick Banting
Andre Ampere
Winston Churchill
- 80 -
John Locke
Bronislaw Malinowski
Bible
Thomas Huxley
Alessandro Volta
Erwin Schrodinger
Wilhelm Roentgen
Louis Pasteur
Bertrand Russell
Jean Lamarck
- 70 -
Samuel Morse
John Wheeler
Nicolaus Copernicus
Robert Fulton
Pierre Laplace
Humphry Davy
Thomas Edison
Lord Kelvin
Theodore Roosevelt
Carolus Linnaeus
- 60 -
Francis Galton
Linus Pauling
Immanuel Kant
Martin Fischer
Robert Boyle
Karl Popper
Paul Dirac
Avicenna
James Watson
William Shakespeare
- 50 -
Stephen Hawking
Niels Bohr
Nikola Tesla
Rachel Carson
Max Planck
Henry Adams
Richard Dawkins
Werner Heisenberg
Alfred Wegener
John Dalton
- 40 -
Pierre Fermat
Edward Wilson
Johannes Kepler
Gustave Eiffel
Giordano Bruno
JJ Thomson
Thomas Kuhn
Leonardo DaVinci
Archimedes
David Hume
- 30 -
Andreas Vesalius
Rudolf Virchow
Richard Feynman
James Hutton
Alexander Fleming
Emile Durkheim
Benjamin Franklin
Robert Oppenheimer
Robert Hooke
Charles Kettering
- 20 -
Carl Sagan
James Maxwell
Marie Curie
Rene Descartes
Francis Crick
Hippocrates
Michael Faraday
Srinivasa Ramanujan
Francis Bacon
Galileo Galilei
- 10 -
Aristotle
John Watson
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Michio Kaku
Isaac Asimov
Charles Darwin
Sigmund Freud
Albert Einstein
Florence Nightingale
Isaac Newton



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