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Carl Sagan

Carl Sagan Quotes

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Famous Carl Sagan Quotes

“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.”

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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.”

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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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“If chimpanzees have consciousness, if they are capable of abstractions, do they not have what until now has been described as 'human rights'? How smart does a chimp have to be before killing him constitutes murder?”

IfsHumansDoeHas BeensHumanityAnimalConsciousnessRightsCapableSmartMurderKillingHuman RightsAbstractionChimpanzees
Book:Dragons of Eden: Speculations on the Evolution of Human Intelligence
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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.”

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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.”

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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.”

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Author:Carl Sagan
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“All of us cherish our beliefs. They are, to a degree, self-defining. When someone comes along who challenges our belief system as insufficiently well-based - or who, like Socrates, merely asks embarrassing questions that we haven't thought of, or demonstrates that we've swept key underlying assumptions under the rug - it becomes much more than a search for knowledge. It feels like a personal assault.”

LoveFeelsWellsSelfAsksBeliefChallengesHavensKeysMoralityDegreesAssumptionCherishVeganAssaultEmbarrassingDefiningBelief SystemsSearch For KnowledgeEmbarrassing Questions
Book:The Demon-Haunted World: Science as a Candle in the Dark
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“After I give lectures-on almost any subject-I am often asked, "Do you believe in UFOs?" I'm always struck by how the question is phrased, the suggestion that this is a matter of belief and not evidence. I'm almost never asked, "How good is the evidence that UFOs are alien spaceships?"”

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Book:The Demon-Haunted World: Science as a Candle in the Dark
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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.”

PeopleIfsHumansWholeCharacterEarthTogetherCommunityGroupsAwarenessBuildingPlanetsMembersLoyaltyBackgroundsCosmosHuman HistoryCharacter BuildingPlanet EarthDivergentPale Blue Dot
Book:Cosmos
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“It's perilous and foolhardy for the average citizen to remain ignorant about global warming, say, or ozone depletion, air pollution, toxic and radioactive wastes, acid rain, topsoil erosion, tropical deforestation, exponential population growth. Jobs and wages depend on science and technology.”

JobsGrowthTechnologyAirDependsCitizensWasteRainAveragePopulationIgnorantGlobal WarmingToxicPollutionWagesAcidScience And TechnologyTropicalErosionPopulation GrowthDeforestationAir PollutionFoolhardyOzoneAcid RainTopsoilOzone DepletionRadioactive Waste
Book:Demon-Haunted World: Science as a Candle in the Dark
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