09.Lakatos Laudan Feyerabendfaculty.poly.edu › ~jbain › philsci › lectures ›...

09.AfterKuhn:Lakatos,Laudan,Feyerabend

• CriticismofKuhn:Scienceisrational,not"mobpsychology"!- AimofPhilosophyofScience:Toproduce"rationalreconstructions"ofhistoricalepisodestomakescientists'decisionsasrationalaspossible(withfootnotesindicatingwhatactually occurred).

1.LakatosandResearchPrograms2.LaudanandResearchTraditions3.FeyerabendandAnythingGoes

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1.LakatosandResearchPrograms

ImreLakatos(1922-1974)

Whig history?

• Insteadofparadigms:

Researchprogram:(i) Typicallymorethanoneatanytimeinagivenfield.(ii) And:Theycompetewithoneanother.

Harumph! One paradigm per field, and competition only during revolutionary science!

Science left in the hands of implicit shared values can be trusted!

No! Science needs the guidance of methodological rules!

Core = essential basic ideas

Protective belt = auxiliary hypotheses used to apply core to descriptions of phenomena

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Theory = core plus protective beltResearch program = sequence of theories with same core

Ex.1:NewtonianresearchprogramCore:ThreeLawsofMotionandLawofGravity.Protectivebelt:- Claimsaboutnatureofmatter.- Claimsaboutstructureofuniverse.- Mathtechniquesusedtoderivepredictionsfromcore.

Preserved over time.

Changed over time.

Core = essential basic ideas

Protective belt = auxiliary hypotheses used to apply core to descriptions of phenomena

Ex.2:DarwinianresearchprogramCore:Organismsevolvebydescentthroughmodificationvia naturalselection(andothercauses).

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Preserved over time.

Changed over time.

Theory = core plus protective beltResearch program = sequence of theories with same core

Protectivebelt:- Claimsaboutrelationsbetweenspecies.- Claimsaboutmechanismsunderlyinginheritance.- Claimsaboutdistributionoforganisms.- Claimsaboutother(non-adaptive)causesofevolution.

Twotypesofchange(a) Withinaresearchprogram.(b) Betweenresearchprograms.

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Progressiveprogram:- Increasingnovel predictivepowerandapplicationtonewcases.

- Successataddressinganomaliesandfendingoffrefutations.

Degeneratingprogram:- Nonovelpredictions,just"savingthephenomena".

- Fallingbehindorjustkeepingupwithattemptstoaddressanomalies.

(a)Changewithinaresearchprogram

Rule1:Changeshouldonlybemadetoaprotectivebelt.Rule2:Changetoaprotectivebeltshouldbeprogressive.

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Progressiveprogram:Copernican(heliostatic)system- Accountedforallknownphenomena.- Novelprediction:Venusdisplaysbothcrescentandgibbousphases.

Degeneratingprogram:Ptolemaic(geostatic)system- Accountedforallknownphenomena.- CanonlyaccountforcrescentphasesofVenus,orgibbousphases,butnotboth!

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Concern:Needa"Rule3"ifyou'reconcernedthatKuhn'saccountisn'trational(i.e.,whatrulegovernschangeacrossparadigmshifts).

(b)Changebetweenresearchprograms- Whatgovernschangeatthislevel("Rule3")?- Whenisarationalscientistjustifiedingivingupadegeneratingresearchprogram?

Tychonic(geostatic)system- Accountedforallknownphenomena,includingbothcrescentandgibbousphasesofVenus!

2.LaudanandResearchTraditions

Larry Laudan

(a) Insteadofresearchprograms:

Researchtradition:moreflexible...(i) Therecanbemovementofideasinandoutofthecore.(ii) Theoriesaremorelooselyrelated.(iii) Latertheoriescancoverlessgroundthanearlierones.(iv) Theoriescanbreakawayfromonetraditionandbe

absorbedintoanother.

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Progress and its Problems(1978)

Ex.Carnot's(1824)theoryofheatengines• Idea:Treatheatinanalogywithwaterasasubstance("caloric")thatproducesmechanicaleffect(work)whenit"falls"fromahotplacetoacoldplace.

coldplace

heatengine

hotplace

⇓ heatin

⇓ heatout⇒ workout

SadiCarnot1796-1832

• Originallyapartofthecaloricresearchtradition.- Core:heatisafluidsubstance.

• Latergetsabsorbedintothekineticresearchtradition.- Core:heatconsistsofthemotionofparticles.

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(b) Twoattitudestowardstheories:

- Acceptance.Toaccept atheoryistotreatitasifitweretrue.- Pursuit.Topursue atheoryistoworkwithitwithoutnecessarilyacceptingit.

Claim:Itisrationaltoboth(i) pursue aresearchtraditionthathasthehighestcurrentrateof

progressinproblem-solving;and(ii) accept thosetheoriesthathavethegreatestproblem-solvingpower.

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• Allowsarationalscientisttoaccepttheideasinamainstreamresearchtradition,butworkonamoremarginaltraditionthathasahigherrateofprogress.

"Scientists tend to begin to pursue and to explore a new research tradition long before its problem-solving success qualifies it to be accepted over its older, more successful rivals."

• Whatistheoptimaldistributionofscientistsacrossarangeofresearchtraditions?- Allworkingonprogressivetraditions?- Somedistributionacrossbothprogressiveanddegeneratetraditions?(Hedgingbets?)

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3.FeyerabendandAnythingGoes

PaulFeyerabend(1924-1994)

Against Method(1975)

• Epistemologicalanarchism:Oppositiontoallsystemsofrulesandconstraintsinscience.

• MotivationfromPopper:Scienceisanaspectofhumancreativity.- Essentialtoallintellectualwork(includingscience):Thefreedevelopmentofcreativityandimagination.

- Anyattempttoestablishrulesofmethodwillresultonlyinastraightjacketingofcreativity.

Harumph! Not during episodes of normal science!

Harumph! Science *is* governed by a rational methodology!

- Are there rational rules for creativity?- Can you be taught to be innovative?

"Anything Goes"!

- Theonlyruleis:

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• MotivationfromMill:- Onindividualliberty.- Geniusesareonlyproducedinanatmosphereoffreedom.

• Feyerabend'sMorale

"It is advisable to let one's inclinations go against reason in any circumstances, for science may profit from it."

- Ex:GalileomarvelingatCopernicanswhoflountestablishedAristotelianworldview

"...through sheer force of intellect [they have] done such violence to their own senses as to prefer what reason told them over that which sensible experience plainly showed them to be the contrary."

GalileoGalilei(1564-1642)

JohnStuartMill(1806-1873)

"By it there are as many possible independent centers of improvement as there are individuals."

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• MotivationfromMill:- Onindividualliberty.- Geniusesareonlyproducedinanatmosphereoffreedom.

• Feyerabend'sMorale

"It is advisable to let one's inclinations go against reason in any circumstances, for science may profit from it."

JohnStuartMill(1806-1873)

"By it there are as many possible independent centers of improvement as there are individuals."

• Concern:Whataboutamechanismfortheelimination ofideas?- "Whatdowedowhenthebridgehastobebuilt?"(Godfrey-Smith)- Claim:Imaginationandcreativityareoneside,butnottheonlyside,ofscience.