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Carl Sagan

Carl Sagan Quotes

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Famous Carl Sagan Quotes

“If some good evidence for life after death were announced, I'd be eager to examine it; but it would have to be real scientific data, not mere anecdote. As with the face on Mars and alien abductions, better the hard truth, I say, than the comforting fantasy.”

IfsRealHardFacesReligionFantasyEvidenceMereAtheistAliensDataBeing RealMarsComfortingAfter DeathLife After DeathAnecdotesHard TruthsAbductionAlien Abduction
Book:Demon-Haunted World: Science as a Candle in the Dark
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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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“[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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“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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“There are many hypotheses in physics of almost comparable brillance and elegance that have been rejected because they did not survive such a confrontation with experiment. In my view, the human condition would be greatly improved if such confrontations and willingness to reject hypotheses were a regular part of our social, political, economic, religious and cultural lives.”

IfsHumansHas BeensWould BePoliticalSocialReligiousViewsEconomicConditionsPhysicsExperimentsRejectsWillingnessHuman ConditionRejectedHypothesisEleganceConfrontation
Author:Carl Sagan
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“'In his celebrated book, 'On Liberty', the English philosopher John Stuart Mill argued that silencing an opinion is "a peculiar evil." If the opinion is right, we are robbed of the "opportunity of exchanging error for truth"; and if it's wrong, we are deprived of a deeper understanding of the truth in its "collision with error." If we know only our own side of the argument, we hardly know even that: it becomes stale, soon learned by rote, untested, a pallid and lifeless truth.'”

IfsKnowsBookTruthEvilOpportunityUnderstandingSidesLibertyOpinionArgumentErrorsPhilosopherDeeperPeculiarDeprivedMillsStaleCollisionLifelessExchangingDeeper UnderstandingSilencing
Book:The Demon-Haunted World: Science as a Candle in the Dark
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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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“When a honeybee dies it releases a death pheromone, a characteristic odour that signals the survivors to remove it from the hive. The corpse is promptly pushed and tugged out of the hive. The death pheromone is oleic acid. What happens if a live bee is dabbed with a drop of oleic acid? Then no matter how strapping and vigourous it might be, it is carried kicking and screaming out of the hive.”

IfsMatterMightHappensScienceDiesReleaseCharacteristicsRemoveSurvivorBeesSignalsCorpsesAcidKickingHivesPheromones
Author:Carl Sagan
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“If we offer too much silent assent about mysticism and superstition - even when it seems to be doing a little good - we abet a general climate in which scepticism is considered impolite, science tiresome, and rigorous thinking somehow stuffy and inappropriate.”

IfsThinkingLittlesSeemsToo MuchOffersSilentClimateMysticismSuperstitionsInappropriateTiresomeScepticismAbet
Book:The Demon-Haunted World: Science as a Candle in the Dark
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“We are rare and precious because we are alive, because we can think as well as we can. We are privileged to influence and perhaps control our future. I believe we have an obligation to fight for life on Earth - not just for ourselves, but for all those, humans and others, who came before us, and to whom we are beholden, and for all those who, if we are wise enough, will come after.”

IfsThinkingBelieveHumansWellsEnoughEarthFightingI BelieveWiseAliveInfluenceObligationOur FuturePrivileged
Book:Billions & Billions: Thoughts on Life and Death at the Brink of the Millennium
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“The chief deficiency I see in the skeptical movement is its polarization: Us vs. Them - the sense that we have a monopoly on the truth; that those other people who believe in all these stupid doctrines are morons; that if you're sensible, you'll listen to us; and if not, to hell with you. This is nonconstructive. It does not get our message across. It condemns us to permanent minority status.”

PeopleIfsBelieveDoeHellStupidMovementMessagesDoctrineChiefsPermanentMinoritiesSensibleMonopolySkepticalDeficiencyMoronPolarization
Author:Carl Sagan
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“The beauty of a living thing is not the atoms that go into it, but the way those atoms are put together. Information distilled over 4 billion years of biological evolution. Incidentally, all the organisms on the Earth are made essentially of that stuff. An eyedropper full of that liquid could be used to make a caterpillar or a petunia if only we knew how to put the components together.”

IfsWayYearsMadeEarthTogetherUsedStuffInformationEvolutionBillionsAtomsOrganismsComponentsLiving ThingsLiquidCaterpillarsPetuniasBiological Evolution
Author:Carl Sagan
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“What a splendid perspective contact with a profoundly different civilization might provide! In a cosmic setting vast and old beyond ordinary human understanding we are a little lonely, and we ponder the ultimate significance, if any, of our tiny but exquisite blue planet, the Earth.... In the deepest sense the search for extraterrestrial intelligence is a search for ourselves.”

IfsHumansLittlesDifferentMightEarthUniverseUnderstandingPlanetsPerspectiveCivilizationOrdinaryLonelyUltimateBlueTinySettingContactSettingsSignificanceCosmicSplendidExquisitePonderingExtraterrestrialBlue Planet
Author:Carl Sagan
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“In college, in the early 1950s, I began to learn a little about how science works, the secrets of its great success, how rigorous the standards of evidence must be if we are really to know something is true, how many false starts and dead ends have plagued human thinking, how our biases can colour our interpretation of evidence, and how often belief systems widely held and supported by the political, religious and academic hierarchies turn out to be not just slightly in error, but grotesquely wrong.”

IfsThinkingKnowsHumansLittlesEndsPoliticalTurnsBeliefReligiousSecretCollegeStandardsEvidenceErrorsColourInterpretationAcademicHierarchyGreat SuccessBelief SystemsDead Ends
Book:Demon-Haunted World: Science as a Candle in the Dark
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