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Carl Sagan

Carl Sagan Quotes

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Famous Carl Sagan Quotes

“If we can't think for ourselves, if we're unwilling to question authority, then we're just putty in the hands of those in power. But if the citizens are educated and form their own opinions, then those in power work for us. In every country, we should be teaching our children the scientific method and the reasons for a Bill of Rights. With it comes a certain decency, humility and community spirit. In the demon-haunted world that we inhabit by virtue of being human, this may be all that stands between us and the enveloping darkness.”

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Author:Carl Sagan
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“It is sometimes said that scientists are unromantic, that their passion to figure out robs the world of beauty and mystery. But is it not stirring to understand how the world actually works — that white light is made of colors, that color is the way we perceive the wavelengths of light, that transparent air reflects light, that in so doing it discriminates among the waves, and that the sky is blue for the same reason that the sunset is red? It does no harm to the romance of the sunset to know a little bit about it.”

KnowsWorldWayLittlesDoeMadeSaidSometimesReasonLightRomanceSciencePassionBitsWhiteAirMysterySkyFiguresColorLittle BitResearchRedScientistBlueWaveHarmPerceiveSunsetPaleTransparentStirringWhite LightPale Blue DotWavelength
Book:Pale Blue Dot: A Vision of the Human Future in Space
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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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“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.”

PeopleThinkingHumansReasonScienceReligionBeliefSupportInstitutionsPositive AtheismRelyProphecyVagueAccuracyPropsPropheticReliabilityScience Vs Religion
Book:Demon-Haunted World: Science as a Candle in the Dark
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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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“If you are only skeptical, then no new ideas make it through to you. You become a crotchety old person convinced that nonsense is ruling the world. (There is, of course, much data to support you.) But every now and then, a new idea turns out to be on the mark, valid and wonderful. If you are too much in the habit of being skeptical about everything, you are going to miss or resent it, and either way you will be standing in the way of understanding and progress.”

IfsWorldWayPersonsIdeasScienceTurnsCoursesUnderstandingSupportToo MuchProgressWonderfulMissingHabitStandingMarkConvincedDataNonsenseNow And ThenSkepticismNew IdeasRulingSkepticalResentSkepticSupport YouOld PersonRuling The World
Author:Carl Sagan
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“Too much openness and you accept every notion, idea, and hypothesis-which is tantamount to knowing nothing. Too much skepticism-especially rejection of new ideas before they are adequately tested-and you're not only unpleasantly grumpy, but also closed to the advance of science. A judicious mix is what we need.”

NeedsIdeasScienceAcceptingKnowledgeKnowingToo MuchAcceptanceNotionRejectionOpennessSkepticismNew IdeasTestedHypothesisGrumpyKnowing Nothing
Author:Carl Sagan
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“We are an intelligent species and the use of our intelligence quite properly gives us pleasure. In this respect the brain is like a muscle. When we think well, we feel good. Understanding is a kind of ecstasy.”

ThinkingGivingFeelsWellsKindUseScienceUnderstandingPleasureBrainRespectIntelligentSpeciesIntelligenceFeel GoodMusclesEcstasyGood Understanding
Book:Broca's brain: reflections on the romance of science
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“Imagine a room awash in gasoline, and there are two implacable enemies in that room. One of them has nine thousand matches. The other has seven thousand matches. Each of them is concerned about who's ahead, who's stronger. Well that's the kind of situation we are actually in. The amount of weapons that are available to the United States and the Soviet Union are so bloated, so grossly in excess of what's needed to dissuade the other, that if it weren't so tragic, it would be laughable. What is necessary is to reduce the matches and to clean up the gasoline.”

IfsWellsKindTwoStatesWould BeScienceUnitedRoomsSituationEnemyUnited StatesImagineAmountNeededThousandWeaponsConcernedTragedyStrongerUnionsCleanSevenAvailableNineTragicExcessSovietSoviet UnionGasolineArms RaceLaughableNuclear Arms Race
Author:Carl Sagan
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“A religion old or new, that stressed the magnificence of the universe as revealed by modern science, might be able to draw forth reserves of reverence and awe hardly tapped by the conventional faiths. Sooner or later such a religion will emerge.”

MightAbleScienceSpiritReligionSpiritualityUniverseAtheismModernDrawsAweReverenceConventionalReservesSooner Or LaterStressedAgnosticismModern ScienceOrganized ReligionMagnificencePantheismPale Blue DotAstronomy And Universe
Book:Pale Blue Dot: A Vision of the Human Future in Space
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“For myself, I like a universe that, includes much that is unknown and, at the same time, much that is knowable. A universe in which everything is known would be static and dull, as boring as the heaven of some weak-minded theologians. A universe that is unknowable is no fit place for a thinking being. The ideal universe for us is one very much like the universe we inhabit. And I would guess that this is not really much of a coincidence.”

ThinkingWould BeScienceUniverseHeavenKnownKnowledgeFitIdealsWeakBoringBoredomDullCoincidenceTheologianStatic
Book:Broca's brain: reflections on the romance of science
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“At the heart of science is an essential balance between two seemingly contradictory attitudes-an openness to new ideas, no matter how bizarre or counterintuitive they may be, and the most ruthless skeptical scrutiny of all ideas, old and new. This is how deep truths are winnowed from deep nonsense.”

HeartMayTwoIdeasMatterScienceAttitudeBalanceEssentialsSmellNonsenseOpennessNew IdeasScentConservationBizarreContradictorySkepticalRuthlessScrutinyOld And New
Author:Carl Sagan
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“Scientists constantly get clobbered with the idea that we spent 27 billion dollars on the Apollo programs, and are asked "What more do you want?" We didn't spend it; it was done for political reasons. ... Apollo was a response to the Bay of Pigs fiasco and to the successful orbital flight of Yuri Gagarin. President Kennedy's objective was not to find out the origin of the moon by the end of the decade; rather it was to put a man on the moon and bring him back, and we did that.”

MenWantIdeasEndsReasonDoneSciencePoliticalPresidentSuccessfulMoonProgramScientistDollarsResponseDecadesBillionsObjectivesFlightPigsApolloFiascoPresident KennedyBay Of Pigs
Author:Carl Sagan
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“[N]o scientist likes to be criticized. ... But you don't reply to critics: "Wait a minute, wait a minute; this is a really good idea. I'm very fond of it. It's done you no harm. Please don't attack it." That's not the way it goes. The hard but just rule is that if the ideas don't work, you must throw them away. Don't waste any neurons on what doesn't work. Devote those neurons to new ideas that better explain the data. Valid criticism is doing you a favor.”

IfsWayIdeasHardDoneScienceWaitingMinutesPleaseWasteCriticismScientistCriticsHarmFavorsLikesDataGood IdeasNew IdeasFavourDoing YouNeurons
Author:Carl Sagan
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“Chlorine is a deadly poison gas employed on European battlefields in World War I. Sodium is a corrosive metal which burns upon contact with water. Together they make a placid and unpoisonous material, table salt. Why each of these substances has the properties it does is a subject called chemistry.”

WorldDoeWarTogetherScienceWaterSubjectsMaterialsTablesPropertyContactSubstanceWar Of The WorldsPoisonGasChemistryMetalsSaltWorld War IEmployedBattlefieldsPlacidSodiumPoison GasChlorine
Book:Broca's brain: reflections on the romance of science
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“A central lesson of science is that to understand complex issues (or even simple ones), we must try to free our minds of dogma and to guarantee the freedom to publish, to contradict, and to experiment. Arguments from authority are unacceptable.”

TryingMindScienceUnderstandingFreedomSimpleIssuesLessonsAuthorityArgumentAccountsComplexesExperimentsGuaranteesDogmaPublish
Book:Billions & Billions: Thoughts on Life and Death at the Brink of the Millennium
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“I believe that even a smattering of such findings in modern science and mathematics is far more compelling and exciting than most of the doctrines of pseudoscience, whose practitioners were condemned as early as the fifth century B.C. by the Ionian philosopher Heraclitus as “nigh -walkers, magicians, priests of Bacchus, priestesses of the wine-vat, mystery-mongers.” But science is more intricate and subtle, reveals a much richer imiverse, and powerfully evokes our sense of wonder.”

ImportantScienceNightUniverseWonderVirtueMysteryCenturyExcitingMathematicsWinePhilosopherDoctrineBeing TrueSubtlePriestsCompellingMagicianFifthEvokeIntricateWalkersSense Of WonderPseudoscienceBacchusVatPriestesses
Author:Carl Sagan
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“There is a reward structure in science that is very interesting: Our highest honors go to those who disprove the findings of the most revered among us. So Einstein is revered not just because he made so many fundamental contributions to science, but because he found an imperfection in the fundamental contribution of Isaac Newton.”

MadeScienceFoundInterestingHonorFindingsHighestAccountsFundamentalsStructureRewardsContributionImperfectionVery InterestingNewtonIsaac
Author:Carl Sagan
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“[Science] 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. It has two rules. First: there are no sacred truths; all assumptions must be critically examined; arguments from authority are worthless. Second: whatever is inconsistent with the facts must be discarded or revised. ... The obvious is sometimes false; the unexpected is sometimes true.”

FirstsTwoSelfSometimesFactsSciencePerfectAuthorityArgumentToolsSacredObviousAssumptionUnexpectedWorthlessOngoingNot PerfectInconsistentDiscardedCorrectingMisusedTrue Fact
Book:Cosmos
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“As agonizing a disease as cancer is, I do not think it can be said that our civilization is threatened by it. ... But a very plausible case can be made that our civilization is fundamentally threatened by the lack of adequate fertility control. Exponential increases of population will dominate any arithmetic increases, even those brought about by heroic technological initiatives, in the availability of food and resources, as Malthus long ago realized.”

ThinkingLongMadeSaidScienceCasesCivilizationDiseaseResourcesIncreasePopulationCancerRealizationHeroicInitiativeLong AgoTechnologicalThreatenedAdequateArithmeticPlausibleFertilityAvailabilityAgonizingMalthus
Author:Carl Sagan
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“Scientists can routinely predict a solar eclipse, to the minute, a millennium in advance. You can go to the witch doctor to lift the spell that causes your pernicious anaemia, or you can take Vitamin B12. If you want to save your child from polio, you can pray or you can inoculate. If you're interested in the sex of your unborn child, you can consult plumb-bob danglers all you want . . . but they'll be right, on average, only one time in two. If you want real accuracy . . . try amniocentesis and sonograms. Try science.”

IfsWantTryingChildrenTwoRealScienceSexCausesMinutesPrayingDoctorsScientistOur ChildrenAverageLiftsYour ChildrenWitchSpellsOne TimeBobAccuracyUnbornVitaminsEclipseMillenniumPerniciousPolioUnborn ChildWitch DoctorsSolar EclipseAnaemia
Author:Carl Sagan
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