05. kuhn: paradigms and immature science 2. immature...
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05.Kuhn:ParadigmsandImmatureScience1.Paradigms
Paradigm(broadsense):apackageofideasandmethodswhichmakeupaviewoftheworldandawayofdoingscience.Paradigm(narrowsense):acollectionofexamplesorexemplarsthatserveasmodels,inspiringanddirectingfurtherwork.
TwoCharacteristics (Kuhnpg.10):• "Sufficientlyunprecedentedtoattractanenduringgroupofadherentsawayfromcompetingmodesofscientificactivity."
• "Sufficientlyopen-endedtoleaveallsortsofproblems...toresolve."
ThomasKuhn(1922-1996)
Examples- Aristotelianphysics(Physica ~300B.C.)- Ptolemaicastronomy(Almagest 2ndcent.A.D.)- Newtoniandynamics(Principia 1687)
1.Paradigms2.ImmatureScience3.Characteristics4.TransitiontoNormalScience5.EstablishmentofNormalSci
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Paradigmscharacterize"NormalScience"
Normalscience:Scientificworkthatoccurswithintheframeworkprovidedbyaparadigm.
ConstrastwithPopper
Scientificmethodisbasedonanopennesstocriticism (scientistsmustbewillingtochangetheirviewsinlightoffalsifyingdata)!
Normalscienceassumesno criticismoffundamentalissues!
- well-organized- agreementonfundamentalissues- extensionofparadigmtocover"nooksandcrannies"- no"criticalstances"or"permanentopenness"
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(ii) Changeassociatedwith"revolutionaryscience"- completeoverthrowofdominantparadigm- nostandards- notionofprogressnotsosimple
Scientificchangeproceedsincrementally (viaconjectureandrefutation).
NewtonExample:
MythofhumbleNewton:- Appealtopriscasapientia?- InsulttoshortrivalRobertHooke?
IfIhaveseenfurtheritisbystandingontheshouldersofgiants.
Twotypesofchangeinscience:
- incremental- standardsofjustificationandrationality- simplenotionofprogress
(i)Changewithinnormalscience.
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StorytoCome:ScientificChangeAccordingtoKuhn
normalscience crisis revolutionary
sciencenormalscience⇒ ⇒ ⇒
REVOLUTION!
REVOLUTION!
"Thebeautyandclearnessofthedynamicaltheorywhichassertsheatandlighttobemodesofmotion,isatpresentobscuredbytwoclouds."(a) Blackbodyradiation:justneedtotweakthetheoryjustabit!(b) Etherdriftnullresults:justneedmorepreciseexperiments!
WilliamThomson,LordKelvin(1900)
Blackbodyradiationcanbetheoreticallyexplainedifwesupposeenergycomesindiscretepackets....let'scallthem"quanta"...
MaxPlanck(1900)
Let'ssupposethereisnoether...andthatmeasurementsoftimeandspacearenotabsolute...
AlbertEinstein (1905)
What comes before normal science and dominant paradigms?
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Example:HistoryofOptics
(a)~1925-present.CurrentParadigm:QuantumFieldTheory• Lightconsistsofphotons:excitationsofaquantizedelectromagneticfield.
2.ImmatureScience
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(b)1800's-1900's.WaveParadigm• Lightconsistsofwavesintheether.
observationscreen
bandsoflightanddarkaccordingtowhetherwavesinterfereconstructivelyordestructively
see
• ThomasYoung'sDouble-SlitExperiment(1800)ThomasYoung(1773-1829)
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observationscreen
butNo!
shouldsee
(b)1800's-1900's.WaveParadigm• Lightconsistsofwavesintheether.• ThomasYoung'sDouble-SlitExperiment(1800)
ThomasYoung(1773-1829)
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(c)1700's-1800's.ParticleParadigm• Lightconsistsofparticles(Newton1704Optiks)
• Refraction:sin(θi)/sin(θr) = vwater/vair• Explanation:Lightparticleisattractedmoretowardswaterparticlesatinterfaceandthusspeedsup.
θi
θrvwater
vair• Reflection:θi =θr• Explanation:Lightparticlesscatterelastically.
θiθr
mirror
IsaacNewton(1643-1727)
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(d)Pre-Newton
Immature Science
• Nodominantparadigm• Manycompetingparadigms- Descartes'(1637)disturbanceintheplenum.
ReneDescartes(1596-1650)
- Hooke(1660's),Huygens(1678)wavetheories.
ChristiaanHuygens
(1629-1695)
- Gassendi(1660's)particletheory.
PierreGassendi
(1592-1655)
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3.CharacteristicsofImmatureScience• Competingviewsneedtoderiveeverythingfromscatch.• Allfactsseemequallyrelevant.• Collectionsoffactswithnoexplanatoryframework- compendiumsandbeastiaries
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4.TransitiontoNormalScience• Oneparadigmmustseembetterthanitsrivals.• Shouldnotexplainallthefacts:shouldbepotentiallyuseful.• Shouldsuggestwhichexperimentsanddirectionsofresearchareworthpursuing.
• OpticsExample:- Newton'sOptiks (1704).Providestheoreticalframework(Newton'stheoryofmotion)withinwhichopticalphenomenacanbeexplained.
- PrestigeofNewton.
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PotentialProblemWhatistherelationbetweenaparadigmandascientificcommunity?• paradigm= whatmembersofascientificcommunityshare.• scientificcommunity= communityunitedunderasingleparadigm.
• Kuhn(postscript):- identifyscientificcommunityfirst (roleofsociology)- then identifyparadigms
• scientificcommunity="practitionersofascientificspecialty"
- professionalinitiations- commonliterature
- similareducations
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5.EstablishmentofNormalScience
• Professionalreputation- basedonextendingparadigmtonewareas,notonreproducingfundamentalresults(sodon'twritetextbooksforaliving).
• Socialfunctionofaparadigm(Kuhnpg.11):- indoctrinationofstudentsintoscientificcommunity
- samemodels- sameproblems- samemethods
• Roleoftextbooks- serveasindependentexplanationsoffundamentalprinciples.
- practitionersofparadigmdon'thavetoalwaysstartfromscratch.
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Claim:Learningproceedsbyreinforcement:- positivereinforcementestablishesbehavior- negativereinforcementeliminatesbehavior
NormalScienceExample
• Extremeform:All humanbehaviorcanbeexplainedintermsofpurelyobservableresponsestoreinforcement.- Inparticular:Therearenosuchthingsasunobservablemental/cognitivestates.
• Thus: "xfeelspain"means"x exhibitscertainbehaviors"
Question: Howshouldweperformoperationsonnewborns?
• Extremebehaviorist:- Newbornscannotverballycommunicate.- Tosay"Newbornisinpain"means"Newbornexhibitscertainbehaviors".- Thus:Justusemusclerelaxantasanesthetic.
• 1950's.Behaviorismparadigminpsychology. Skinner,B.F.(1953)ScienceandHuman
Behavior
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