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Carl Sagan

Carl Sagan Quotes

Astronomer

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Famous Carl Sagan Quotes

“The major religions on the Earth contradict each other left and right. You can't all be correct. And what if all of you are wrong? It's a possibility, you know. You must care about the truth, right? Well, the way to winnow through all the differing contentions is to be skeptical. I'm not any more skeptical about your religious beliefs than I am about every new scientific idea I hear about. But in my line of work, they're called hypotheses, not inspiration and not revelation.”

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Book:Contact
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“It has been said that astronomy is a humbling and character-building experience. There is perhaps no better demonstration of the folly of human conceits than this distant image of our tiny world. To me, it underscores our responsibility to deal more kindly with one another and to preserve and cherish the pale blue dot, the only home we've ever known.”

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Book:Pale Blue Dot: A Vision of the Human Future in Space
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“The Platonists and their Christian successors held the peculiar notion that Earth was tainted and somehow nasty, while the heavens were perfect and divine. The fundamental idea that the Earth is a planet, that we are citizens of the Universe, was rejected and forgotten. This idea was first argued by Aristarchus, born on Samos three centuries after Pythagoras. Aristarchus was one of the last of the Ionian scientists. By this time, the center of intellectual enlightenment had moved to the great Library of Alexandria. Aristarchus was the first person to hold that the Sun rather than the Earth is at the center of the planetary system that all the planets go around the Sun rather than the Earth. Typically, his writings on this matter are the lost. From the size of the Earth's shadow on the Moon during a lunar eclipse, he deduced that the Sun had to be much larger than the Earth, as well as very far away. He may then have reasoned that it is absurd for so large a body as the Sun to revolve around so small a body as the Earth. He put the Sun at the center, made the Earth rotate on its axis once a day or orbit the Sun once a year. It is the same idea we associate with the name of Copernicus, whom Galileo described as the 'restorer and confirmer', not the inventor, of the heliocentric hypothesis. For most of the 1,800 years between Aristarchus and Copernicus nobody knew the correct disposition of the planets, even though it had been laid out perfectly clearly around 280 B.C.”

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Book:Cosmos
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“One consequence of this train of argument is that, even if civilizations commonly arise on planets throughout the Galaxy, few of them will be both long-lived and nontechnological. Since hazards from asteroids and comets must apply to inhabited planets all over the Galaxy, if there are such, intelligent beings everywhere will have to unify their home worlds politically, leave their planets, and move small nearby worlds around. Their eventual choice, as ours, is spaceflight or extinction.”

EarthPale Blue DotSpaceflightCarl Sagan
Book:Pale Blue Dot: A Vision of the Human Future in Space
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“The Earth is the only world known so far to harbor life. There is nowhere else, at least in the near future, to which our species could migrate. Visit, yes. Settle, not yet. Like it or not, for the moment the Earth is where we make our stand. It has been said that astronomy is a humbling and character-building experience. There is perhaps no better demonstration of the folly of human conceits than this distant image of our tiny world. To me, it underscores our responsibility to deal more kindly with one another, and to preserve and cherish the pale blue dot, the only home we’ve ever known.”

EarthAstronomyPale Blue DotCarl Sagan
Book:Pale Blue Dot: A Vision of the Human Future in Space
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“If we are willing to contemplate nuclear war and the wholesale destruction of our emerging global society, should we not also be willing to contemplate a wholesale restructuring of our societies? From an extraterrestrial perspective, our global civilization is clearly on the edge of failure in the most important task it faces: to preserve the lives and well-being of the citizens of the planet. Should we not then be willing to explore vigorously, in every nation, major changes in the traditional ways of doing things, a fundamental redesign of economic, political, social and religious institutions? Faced with so disquieting an alternative, we are always tempted to minimize the seriousness of the problem, to argue that those who worry about doomsday’s are alarmists; to hold that fundamental changes in our institutions are impractical or contrary to ‘human nature’, as if nuclear war were practical, or as if there were only one human nature. Full-scale nuclear war has never happened. Somehow this is taken to imply that it never will. But we can experience it only once. But then it will be too late to reformulate the statistics.”

WarEarthPeaceSelf DestructionRestructure
Book:Cosmos
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“The Cosmos extends, for all practical purposes, forever. After a brief sedentary hiatus, we are resuming our ancient nomadic way of life. Our remote descendants, safely arrayed on many worlds throughout the Solar System and beyond, will be unified by their common heritage, by their regard for their home planet, and by the knowledge that, whatever other life may be, the only humans in all the Universe come from Earth. They will gaze up and strain to find the blue dot in their skies. They will love it no less for its obscurity and fragility. They will marvel at how vulnerable the repository of all our potential once was, how perilous our infancy, how humble our beginnings, how many rivers we had to cross before we found our way.”

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Book:Pale Blue Dot: A Vision of the Human Future in Space
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“Look again at that dot. That's here. That's home. That's us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The aggregate of our joy and suffering, thousands of confident religions, ideologies, and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every "superstar," every "supreme leader," every saint and sinner in the history of our species lived there-on a mote of dust suspended in a sunbeam.”

EarthScienceConservationEnvironmentalism
Author:Carl Sagan
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“We have held the peculiar notion that a person or society that is a little different from us, whoever we are, is somehow strange or bizarre, to be distrusted or loathed. Think of the negative connotations of words like alien or outlandish. And yet the monuments and cultures of each of our civilizations merely represent different ways of being human. An extraterrestrial visitor, looking at the differences among human beings and their societies, would find those differences trivial compared to the similarities. The Cosmos may be densely populated with intelligent beings. But the Darwinian lesson is clear: There will be no humans elsewhere. Only here. Only on this small planet. We are a rare as well as an endangered species. 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.”

EarthPeaceDifferencesCultures
Book:Cosmos
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“The cosmic calendar compresses the local history of the universe into a single year. If the universe began on January 1st it was not until May that the Milky Way formed. Other planetary systems may have appeared in June, July and August, but our Sun and Earth not until mid-September. Life arose soon after. 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.”

IfsWayYearsHumansMayEarthLastsUniverseSunMinutesLocalsSecondsCosmicSeptemberJuneJulyAugustDecemberJanuaryCalendarsLast MinuteMilky WayLocal HistoryJanuary 1st
Author:Carl Sagan
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“We've begun at last to wonder about our origins, star stuff contemplating the stars, organized collections of ten billion billion billion atoms contemplating the evolution of matter, tracing that long path by which it arrived at consciousness here on the planet Earth and perhaps throughout the cosmos. Our obligation to survive and flourish is owed not just to ourselves but also to that cosmos, ancient and vast, from which we spring.”

LongMatterEarthLastsStarsStuffConsciousnessWonderPathPlanetsEvolutionTenSpringAncientBillionsObligationOrganizedCollectionsCosmosAtomsContemplatingPlanet EarthTracing
Author:Carl Sagan
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“I’m struck again by the irony that spaceflight-conceived in the cauldron of nationalist rivalries and hatreds-brings with it a stunning transnational vision. You spend even a little time contemplating the Earth from orbit and the most deeply engrained nationalisms begin to erode. They seem the squabbles of mites on a plum.”

LittlesSeemsEarthVisionHatredIronyNationalismContemplatingRivalryLittle TimeStunningOrbitPlumsErodeCauldronsSquabblesSpaceflight
Book:Pale Blue Dot: A Vision of the Human Future in Space
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“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”

WorldHumansWellsWholeEarthFilmStarsKnownRocksScalesMetalsSolitaryMultitudesObscureWell KnownGalaxyApolloLumpsAstronomersInconsequential
Book:Pale Blue Dot: A Vision of the Human Future in Space
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“There is no other species on Earth that does science. It is, so far, entirely a human invention, evolved by natural selection in the cerebral cortex for one simple reason: it works. It is not perfect. It can be misused. It is only a tool. But it is by far the best tool we have, self-correcting, ongoing, applicable to everything.”

HumansDoeSelfReasonEarthNaturalSimplePerfectToolsSpeciesInventionWorking ItSelectionOngoingNot PerfectNatural SelectionCorrectingCerebralMisusedHuman Inventions
Book:Cosmos
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“At a few hundred kilometers altitude, the Earth fills half your sky, and the band of blue that stretches from Mindanao to Bombay, which your eye encompasses in a single glance, can break your heart with its beauty. Home you think. Home. This is my world. This is where I come from. Everyone I know, everyone I ever heard of, grew up down there, under that relentless and exquisite blue.”

ThinkingKnowsWorldHeartHomeEyeEarthHalfBreakHeardSkyGrewBandGrew UpHundredBlueGlancesExquisiteRelentlessBreak Your HeartBombay
Book:Contact
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“An extraterrestrial being, newly arrived on Earth - scrutinizing what we mainly present to our children in television, radio, movies, newspapers, magazines, the comics, and many books - might easily conclude that we are intent on teaching them murder, rape, cruelty, superstition, credulity, and consumerism. We keep at it, and through constant repetition many of them finally get it.”

ChildrenBookMightEarthTeachingTelevisionMurderOur ChildrenConstantRadioNewspapersCrueltyMagazinesSuperstitionsConsumerismRepetitionCredulityExtraterrestrial
Book:Demon-Haunted World: Science as a Candle in the Dark
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“Perhaps, in retrospect, there would be little motivation even for malevolent extraterrestrials to attack the Earth; perhaps, after a preliminary survey, they might decide it is more expedient just to be patient for a little while and wait for us to self-destruct.”

LittlesSelfMightWould BeEarthMotivationWaitingPatientBe PatientSurveysRetrospectSelf Destruct
Book:Billions & Billions: Thoughts on Life and Death at the Brink of the Millennium
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“Coal, oil and gas are called fossil fuels, because they are mostly made of the fossil remains of beings from long ago. The chemical energy within them is a kind of stored sunlight originally accumulated by ancient plants. Our civilization runs by burning the remains of humble creatures who inhabited the Earth hundreds of millions of years before the first humans came on the scene. Like some ghastly cannibal cult, we subsist on the dead bodies of our ancestors and distant relatives. - Dr. Carl Sagan”

YearsFirstsHumansKindLongMadeBodyRunningEarthEnergyMillionsCivilizationSceneCreaturesRemainsPlantAncientHumbleOilBurningFuelGasChemicalsAncestorSunlightLong AgoDrsConservationCultCoalFossilsFossil FuelGhastlyCannibalOil And GasBurning Fossil FuelsSagan
Book:Billions & Billions: Thoughts on Life and Death at the Brink of the Millennium
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“A new consciousness is developing which sees the earth as a single organism and recognizes that an organism at war with itself is doomed. We are one planet. One of the great revelations of the age of space exploration is the image of the earth finite and lonely, somehow vulnerable, bearing the entire human species through the oceans of space and time.”

HumansWarAgeEarthScienceSpaceConsciousnessPlanetsOceanLonelySpeciesVulnerableDevelopingRevelationsExplorationOrganismsDoomedFiniteTime And SpaceSpace ExplorationHuman Species
Author:Carl Sagan
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“The surface of the Earth is the shore of the cosmic ocean. On this shore, we've learned most of what we know. Recently, we've waded a little way out, maybe ankle-deep, and the water seems inviting. Some part of our being knows this is where we came from. We long to return, and we can, because the cosmos is also within us. We're made of star stuff. We are a way for the cosmos to know itself.”

KnowsWayLittlesLongMadeSeemsEarthStarsStuffWaterReturnOceanSurfaceCosmosShoreCosmicInvitingAnklesWhere We Came
Author:Carl Sagan
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“The Hindu religion is the only one of the world’s great faiths dedicated to the idea that the Cosmos itself undergoes an immense, indeed an infinite, number of deaths and rebirths. It is the only religion in which the time scales correspond, no doubt by accident, to those of modern scientific cosmology. Its cycles run from our ordinary day and night to a day and night of Brahma, 8.64 billion years long, longer than the age of the Earth or the Sun and about half the time since the Big Bang.”

WorldYearsLongIdeasBigsRunningAgeEarthNightNumbersHalfSunModernOrdinaryInfiniteBillionsScalesCosmosCyclesDedicatedHinduismImmenseRebirthBangsDay And NightCosmologyGreat FaithBrahmaHindu ReligionOrdinary DaysDeath And Rebirth
Author:Carl Sagan
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“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?”

IfsKnowsHumansWould BeEarthValuesHuman BeingsMiracleGreenGrassMarsBladesPatchesCommonplacePricelessSpace ExplorationCosmologyDescendantsBlades Of Grass
Book:Pale Blue Dot: A Vision of the Human Future in Space
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“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.”

LittlesLightEarthScienceStarsDifficultReligiousSpaceViewsPlanetsBlueBoundariesFragileEvidentOur PlanetFadingChauvinismCitadelsCrescentPoints Of Light
Author:Carl Sagan
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“The Earth is a very small stage in a vast cosmic arena. Think of the rivers of blood spilled by all those generals and emperors so that, in glory and triumph, they could become the momentary masters of a fraction of a dot. Think of the endless cruelties visited by the inhabitants of one corner of this pixel on the scarcely distinguishable inhabitants of some other corner, how frequent their misunderstandings, how eager they are to kill one another, how fervent their hatreds.”

ThinkingEarthUniverseCompassionBloodStageHumilityMastersGloryRiversHatredCornersEndlessCrueltyTriumphCosmosCosmicPaleMisunderstandingArenaEmperorFractionsDotsMomentaryVastnessFerventCosmic ConsciousnessPale Blue DotAcross The UniverseAstronomy And UniversePixels
Book:Pale Blue Dot: A Vision of the Human Future in Space
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“We can make a similar examination, but with greater uncertainty, of the extraterrestrial hypothesis that holds that a wide range of UFOs viewed on the planet Earth are space vehicles from planets of other stars.”

EarthStarsSpaceGreaterPlanetsWideUncertaintyRangeVehicleHypothesisExaminationUfoPlanet EarthExtraterrestrial
Book:Carl Sagan's Cosmic Connection: An Extraterrestrial Perspective
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“Human history can be viewed as a slowly dawning awareness that we are members of a larger group Groups of people from divergent ethnic and cultural backgrounds working in some sense together [is] surely a humanizing and character building experience. If we are to survive, our loyalties must be broadened further, to include the whole human community, the entire planet Earth.”

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Book:Cosmos
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“When you look more generally at life on Earth, you find that it is all the same kind of life. There are not many different kinds; there's only one kind. It uses about fifty fundamental biological building blocks, organic molecules.”

LooksKindDifferentUseEarthBuildingFundamentalsBlockFiftyDifferent KindsMoleculesBuilding Blocks
Book:The Varieties of Scientific Experience: A Personal View of the Search for God
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“There is perhaps no better a demonstration of the folly of human conceits than this distant image of our tiny world.”

WorldHumansEarthSpaceTinyAstronomyFollyCosmosPaleDemonstrationConceitEarth DayVastnessCosmic ConsciousnessBeautiful EarthEarth And SkyPale Blue DotInspirational EarthAcross The UniverseMy SpaceAstronomy And UniverseHuman Folly
Book:Pale Blue Dot: A Vision of the Human Future in Space
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“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.”

KnowsYearsFirstsMadeSelfHappensEarthChoicesUniverseNextSpaceDependsEvolutionOceanDestructionBillionsLegacyCosmosHeritageMeaninglessCosmicTime And SpaceHere And NowAwakenedSelf DestructionVastness
Author:Carl Sagan
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