Embed Size (px)
Citation preview
33# REDISCOVERING SCHOOL SCIENCE
Arvind Kumar
Understandingnatureofscienceis,now,widelyperceivedtobeavitallearningoutcomeofscienceeducation.Inthisarticle,webrieflydiscusstherationaleforintroducing‘natureofscience’inschoolsciencecurricula,itsevolvingperspectives,andtheapproacheswemayadopttoenablethelearningofthistopic.
Introduction
hatisscience?ItisnotuncommonforW textbooksofsciencetobeginwiththisquestionintheintroductorychapter,
devoteafewparagraphstoit,andthengetonquicklywithwhatisregardedasthemainstuffofscience:itsempiricalfacts,laws,theories,etc.Typically,thebookswouldsay:scienceinvolvesmakingsystematicunbiasedobservationsofnature,doingcarefulexperiments,anddrawinglogicalinferencesfromthem.Inthisway,wearriveatthelawsofnature.Wesuggesthypothesestounderstandtheempiricallaws,whichthenleadustobuildelaboratetheoriestoexplaintheknownphysicalphenomena.Theoriesalsopredictnewphenomena.Ifthepredictionsareverified,thetheoryisconfirmed.Sciencebowstonoauthority;itisobjectiveknowledgeobtainedfromobservationsandexperiments.
Thereismuchthatmakessenseinthisdescriptionofnatureofscience,simplisticthoughitwillseemaswediscussitfurther.Butfirst,wemustaskwhyitisnecessaryatalltoteachnatureofsciencewhenthereissolittletimetofinishthe‘moreimportant’partsofthesubject.
Whyteach‘NatureofScience’(NOS)
Torespondtothisquestion,wemustpausetoreflectonwhatisthepurposeofteachingscienceinschool.ScienceisacompulsorysubjectintheIndianschoolcurriculumtilltheendofsecondaryschool.Amajorityofstudentswillceasetogoforfurtherformaleducation;ofthosewhodopursuehigherstagesofeducation,manywouldgotocommerce,artsandotherstreams.Therefore,onlyasmallfractionofstudentsfinishingClassXwillchoosetocontinueinthesciencestream,andastillsmallerfractionofthisnumberwillgoontobecomescientistsorotherprofessionalswhodirectlyneedscienceanditsapplicationsintheircareers.Thusmostpeopleareunlikelytoneedanyscientificcontentknowledge(ofthekindlearntatschool)intheirprofessions.
Why,then,havewemadescienceeducationcompulsoryattheschoollevel?Clearly,thiswouldmakesenseonlyifthemainpurposeofschoolscienceeducationwassomewhatbroadandnotlimitedtospecificsciencecontentonly.Thegoalsofschoolscienceeducationhavebeendebatedendlessly,oftenwithdifferingideologicalstances;butfewwoulddisagreethataprincipalgoalisto
NATURE OF SCIENCE
3534 REDISCOVERING SCHOOL SCIENCE
inductivegeneralizationfromunbiasedobservationsofnature,andcontrolledexperiments.Baconforesawtheimmensepowerofthisnewmethodinnotonlypredicting,butalsocontrollingphenomena.
Inthebeginningofthe20thcentury,aninfluentialgroupofphilosophersofscienceundertooktoformulateamorerigorousversionofthescientificmethod.Briefly,theyregardedastatementoranassertionmeaningfulonlyifitwaseitherlogicallyself-evident,orcouldbeputinaverifiableform;sciencemustonlyhavesuchmeaningfulstatements.Forconvenience,wemayusetheoreticaltermslike‘atom’,‘gene’,‘valency’,butultimately,allscientificassertionsmustbereducibletoobservationstatements.Bythisstrictcriterion,poetryismeaningless,ifharmless,whileametaphysicalassertionisbothmeaninglessandharmful,sinceitpurportstobetrue!Theproponentsofthisphilosophy,calledlogicalpositivism(andinitslater,moremoderate,version,calledlogicalempiricism),couldnotrealisetheirambitionoftranslatingallofscienceintheseterms.
Inthesamespiritofanalysingthescientificmethod,butdistinctfromlogicalpositivisminmanyways,wasthephilosophyofKarlPopper.Popperwasdrivenbyadesiretodifferentiatebetweenscienceand,whatheregardedas,pseudoscience.Heisfamousforhisfalsificationcriterion:atheoryisnotscientificifthereisnowaytorefuteit.Goodscientifictheoriesgiveunambiguouspredictionsthatarefalsifiable.Ifthepredictionisverified,youhavenotconfirmedthetheory;youhavesimplynotshownittobefalseyet.Thisispreciselywherepseudo-sciencesdiffer—theydonotgiveclear-cuttestablepredictions,andcanaccommodateanyobservation.Popperadvocatedthatscienceshould‘stickitsneckout’,giveboldnewpredictions,andsuggestcriticalexperimentsthathavethepotentialtofalsifyatheory.PopperwasinspiredbyEinstein’swork,andhisideasusuallyresonatewithscientists;heisoftencalledthescientists’philosopher.
Inanincisivecriticismofthesedominantideas,aroundthe1950s,Quinearguedthatascientifictheoryisacomplexwebofinterconnectedassumptionsandclaimsthatrelatetoexperienceasawhole.Consequently,itisnotpossibletotestorfalsifyeachstatementofthetheoryinisolation.Hecalledforaholistictheoryofmeaningandtesting.
Byepistemicbeliefswemeanourideasonhowscientificknowledgeisgeneratedandjustified;byontologicalbeliefswemeanbroadlyourideasonthebasiccategoriesofobjectsthatexistinnature.Forexample,classicalphysicsregardsparticlesandelectromagneticwavesastwodistinctontologicalcategories,adistinctionthatgetsblurredinmodernphysics.
generateaninformedsciencecitizenryinthecountry.Studentsneedtogrowintocitizenswhohaveafeelforwhatscienceisabout,whatmethodsandprocessesareinvolvedingeneratingnewscience,andwhatrelationsciencehaswithtechnologyandsociety.Thishasbecomeincreasinglynecessary,becausescienceandtechnologyaredeeplyimpactingourwaysofliving.Citizensneedtohavesomeminimalfamiliaritywithmoderntechnology,itspossiblebenefitsandrisks;itsimpactonourhealthandenvironment,etc.;sothattheycanmakeinformedchoices,andformulatematureopinionsabouttheseissues.Science,somewouldargue,hasusheredintheAgeofReason,andcanhelpencouragearationaloutlookaboutlife(thoughatpresentthisseemslikeadistantgoal!).These,andseveralotheralliedobjectives,aresometimes,clubbedunderthehead‘scienceandtechnologyliteracy’.Therearenumerousvariantsofthisterm,andmanyshadesandnuances,but,perhaps,itissafetosaythattherationaleforteachingNOSistiedcloselytothisgeneralgoalofschoolscienceeducation.
DoesthatmeanweincorporatetheteachingofNOSattheexpenseofthe‘real’contentofscience?Indoingso,dowenotjeopardisethequalityofknowledgeofourfuturescientists?Willourcountrynotloseoutonitscompetitiveedgeinscience?And,inanycase,willtheteachingofNOSbeofanyrealuseforthelargermajorityofstudentswehaveinmind?
Theseconcerns,widelysharedamongteachers(andscientists),arisenaturallybecausetherelevanceofNOSintheschoolsciencecurriculum,anditspedagogy,arestillnotveryclear.First,itisnotcorrecttothinkthatNOSisrelevantonlyforthenon-sciencegroupindicatedabove,andthatfuturescientistsneedtofocusonlyonacquiringconceptualknowledgethatisatthecoreoftheirsubject.Onthecontrary,thereisanincreasingfeelingamongeducatorsthatlearningNOScandeepenone’sunderstandingofthesubjectitself.Forthepastfewdecades,scienceeducationresearchershavecarriedoutdetailedstudiesatdifferentlevels,ontheepistemicandontologicalbeliefsofstudentswithregardtotheirsubject,
andhaveconcludedthatthesecouldhaveabearingontheircriticalunderstandingofthecontentofthesubject.
Inshort,understandingnatureofscienceisnotonlyrelevantforthegeneralgoalofpromotingscienceandtechnologyliteracy;itisjustasrelevanttoasciencestudent,indevelopingadeeperappreciationforhersubject.
Second,whatisenvisagedisnotto‘dilute’thecontentofscience,butrathertouseitimaginatively,asameanstoteachNOS,amongotherthings.Inotherwords,NOSistobetaught,notbypreachingabstractgeneralitiessetasidein
aseparateunitofthebook;itistobeputincontextbyinterleavingitwiththe
contentofscience.Beforeweseehowthatmightbedone,wemustfirstbroadlyagreeonwhatourviewsareon‘natureofscience’.
Natureofscience:evolvingperspectives
Thenatureofsciencehasbeenasubjectof
philosophicalinquiryallthroughhistory,andcontinues
tobeso,evennow.Assciencehasadvanced,particularlyinthelastfour
centuries,sohaveourideasaboutthenatureofscience.When,inthe16thand17thcenturies,modernsciencewasbeingshapedbytheworkofGalileo,Descartes,KeplerandNewton;FrancisBaconwasformulating,whatwenowcall,thescientificmethod.Roughlyspeaking,theintroductoryparagraphofthisarticlereplicatesBacon’sideasofnatureofscience.TheessenceofBacon’sideasisthatscienceis
Philosophiesseekingarationalbasisofscience,clearlyseparatedthecontextofdiscovery(theintuitivecreativephaseofscienceembeddedinparticularsocialsettings)fromthecontextofjustification(criticalphilosophicalscrutinyoftheoriesclaimedtobecorrect).Theformerwasthoughttobelongtotherealmofpsychology/sociology.Thisdistinctionkepttheactualpracticeofscience,largely,beyondtheirpurview.Inotherwords,theattemptwastoformulatewhatthescientificmethodshouldbe,ratherthanwhatitwasactually.
Around1960s,ThomasKuhn’s,nowfamous,book‘TheStructureofScientificRevolutions’,markedthebeginningofamajortransformationofourideasofnatureofscience,andhowitprogresses.Analyzingsomekeymilestonesinthehistoryofscience(suchastheCopernicanrevolution),Kuhnconcludedthatscientistsnormallyworkwithinacertainparadigm;theyareconservativeuptoapoint,anddonotabandontheirexistingtheorieseveninthefaceofsomeanomalies(disagreementwithexperiment).However,whentheanomaliesarestarkandaccumulatewithtime,thereisacrisisinnormalscience,andtheexistingparadigmisquestioned.Allkindsofalternativeideasfloatduringthecrisis,outofwhichsomepromisingnewideasbegintoattractconsensus,oftenbecauseofsomeparticularlystrikingexemplars.Anewparadigmisborn,andnormalsciencereturns,inwhichscientistsworkoutthedetailsandapplicationsofthechangedparadigm.
ThekeypointtonoteinKuhn’sphilosophyisthattheparadigmshiftisnotgovernedbyapurelyrationalprocess;itinvolvesasocialconsensusinthescientificcommunity.Theadherencetoanexistingparadigminnormalscienceissecuredthroughtraininginourcollegesandgraduateschools.NoteverybodyagreedwithKuhn.LakotosfoundtheunderminingoftherationalbasisofscientificprogressimpliedinKuhn’sideasunacceptable,anddevelopedhisowntheoryintermsofthenotionofcompeting‘researchprogrammes’.Feyerabenddismissedtheveryideathatthereisanyclearmethodinthewayscienceevolves.Hisphilosophyisoftensummarizedbythecatchyline:‘anythinggoes’.Hisnotedbook‘AgainstMethod’celebratescreativityinscienceandadvocatesfreedomofimagination.ThuswhileLakotosfoundthedisorderinherentinKuhn’sviewofsciencealarming,FeyerebendcriticizedKuhnforjusttheoppositereason--forhisorderlyandmechanicalviewofscientific
FrancisBacon'sworkestablishedtheScientificMethod
3534 REDISCOVERING SCHOOL SCIENCE
inductivegeneralizationfromunbiasedobservationsofnature,andcontrolledexperiments.Baconforesawtheimmensepowerofthisnewmethodinnotonlypredicting,butalsocontrollingphenomena.
Inthebeginningofthe20thcentury,aninfluentialgroupofphilosophersofscienceundertooktoformulateamorerigorousversionofthescientificmethod.Briefly,theyregardedastatementoranassertionmeaningfulonlyifitwaseitherlogicallyself-evident,orcouldbeputinaverifiableform;sciencemustonlyhavesuchmeaningfulstatements.Forconvenience,wemayusetheoreticaltermslike‘atom’,‘gene’,‘valency’,butultimately,allscientificassertionsmustbereducibletoobservationstatements.Bythisstrictcriterion,poetryismeaningless,ifharmless,whileametaphysicalassertionisbothmeaninglessandharmful,sinceitpurportstobetrue!Theproponentsofthisphilosophy,calledlogicalpositivism(andinitslater,moremoderate,version,calledlogicalempiricism),couldnotrealisetheirambitionoftranslatingallofscienceintheseterms.
Inthesamespiritofanalysingthescientificmethod,butdistinctfromlogicalpositivisminmanyways,wasthephilosophyofKarlPopper.Popperwasdrivenbyadesiretodifferentiatebetweenscienceand,whatheregardedas,pseudoscience.Heisfamousforhisfalsificationcriterion:atheoryisnotscientificifthereisnowaytorefuteit.Goodscientifictheoriesgiveunambiguouspredictionsthatarefalsifiable.Ifthepredictionisverified,youhavenotconfirmedthetheory;youhavesimplynotshownittobefalseyet.Thisispreciselywherepseudo-sciencesdiffer—theydonotgiveclear-cuttestablepredictions,andcanaccommodateanyobservation.Popperadvocatedthatscienceshould‘stickitsneckout’,giveboldnewpredictions,andsuggestcriticalexperimentsthathavethepotentialtofalsifyatheory.PopperwasinspiredbyEinstein’swork,andhisideasusuallyresonatewithscientists;heisoftencalledthescientists’philosopher.
Inanincisivecriticismofthesedominantideas,aroundthe1950s,Quinearguedthatascientifictheoryisacomplexwebofinterconnectedassumptionsandclaimsthatrelatetoexperienceasawhole.Consequently,itisnotpossibletotestorfalsifyeachstatementofthetheoryinisolation.Hecalledforaholistictheoryofmeaningandtesting.
Byepistemicbeliefswemeanourideasonhowscientificknowledgeisgeneratedandjustified;byontologicalbeliefswemeanbroadlyourideasonthebasiccategoriesofobjectsthatexistinnature.Forexample,classicalphysicsregardsparticlesandelectromagneticwavesastwodistinctontologicalcategories,adistinctionthatgetsblurredinmodernphysics.
generateaninformedsciencecitizenryinthecountry.Studentsneedtogrowintocitizenswhohaveafeelforwhatscienceisabout,whatmethodsandprocessesareinvolvedingeneratingnewscience,andwhatrelationsciencehaswithtechnologyandsociety.Thishasbecomeincreasinglynecessary,becausescienceandtechnologyaredeeplyimpactingourwaysofliving.Citizensneedtohavesomeminimalfamiliaritywithmoderntechnology,itspossiblebenefitsandrisks;itsimpactonourhealthandenvironment,etc.;sothattheycanmakeinformedchoices,andformulatematureopinionsabouttheseissues.Science,somewouldargue,hasusheredintheAgeofReason,andcanhelpencouragearationaloutlookaboutlife(thoughatpresentthisseemslikeadistantgoal!).These,andseveralotheralliedobjectives,aresometimes,clubbedunderthehead‘scienceandtechnologyliteracy’.Therearenumerousvariantsofthisterm,andmanyshadesandnuances,but,perhaps,itissafetosaythattherationaleforteachingNOSistiedcloselytothisgeneralgoalofschoolscienceeducation.
DoesthatmeanweincorporatetheteachingofNOSattheexpenseofthe‘real’contentofscience?Indoingso,dowenotjeopardisethequalityofknowledgeofourfuturescientists?Willourcountrynotloseoutonitscompetitiveedgeinscience?And,inanycase,willtheteachingofNOSbeofanyrealuseforthelargermajorityofstudentswehaveinmind?
Theseconcerns,widelysharedamongteachers(andscientists),arisenaturallybecausetherelevanceofNOSintheschoolsciencecurriculum,anditspedagogy,arestillnotveryclear.First,itisnotcorrecttothinkthatNOSisrelevantonlyforthenon-sciencegroupindicatedabove,andthatfuturescientistsneedtofocusonlyonacquiringconceptualknowledgethatisatthecoreoftheirsubject.Onthecontrary,thereisanincreasingfeelingamongeducatorsthatlearningNOScandeepenone’sunderstandingofthesubjectitself.Forthepastfewdecades,scienceeducationresearchershavecarriedoutdetailedstudiesatdifferentlevels,ontheepistemicandontologicalbeliefsofstudentswithregardtotheirsubject,
andhaveconcludedthatthesecouldhaveabearingontheircriticalunderstandingofthecontentofthesubject.
Inshort,understandingnatureofscienceisnotonlyrelevantforthegeneralgoalofpromotingscienceandtechnologyliteracy;itisjustasrelevanttoasciencestudent,indevelopingadeeperappreciationforhersubject.
Second,whatisenvisagedisnotto‘dilute’thecontentofscience,butrathertouseitimaginatively,asameanstoteachNOS,amongotherthings.Inotherwords,NOSistobetaught,notbypreachingabstractgeneralitiessetasidein
aseparateunitofthebook;itistobeputincontextbyinterleavingitwiththe
contentofscience.Beforeweseehowthatmightbedone,wemustfirstbroadlyagreeonwhatourviewsareon‘natureofscience’.
Natureofscience:evolvingperspectives
Thenatureofsciencehasbeenasubjectof
philosophicalinquiryallthroughhistory,andcontinues
tobeso,evennow.Assciencehasadvanced,particularlyinthelastfour
centuries,sohaveourideasaboutthenatureofscience.When,inthe16thand17thcenturies,modernsciencewasbeingshapedbytheworkofGalileo,Descartes,KeplerandNewton;FrancisBaconwasformulating,whatwenowcall,thescientificmethod.Roughlyspeaking,theintroductoryparagraphofthisarticlereplicatesBacon’sideasofnatureofscience.TheessenceofBacon’sideasisthatscienceis
Philosophiesseekingarationalbasisofscience,clearlyseparatedthecontextofdiscovery(theintuitivecreativephaseofscienceembeddedinparticularsocialsettings)fromthecontextofjustification(criticalphilosophicalscrutinyoftheoriesclaimedtobecorrect).Theformerwasthoughttobelongtotherealmofpsychology/sociology.Thisdistinctionkepttheactualpracticeofscience,largely,beyondtheirpurview.Inotherwords,theattemptwastoformulatewhatthescientificmethodshouldbe,ratherthanwhatitwasactually.
Around1960s,ThomasKuhn’s,nowfamous,book‘TheStructureofScientificRevolutions’,markedthebeginningofamajortransformationofourideasofnatureofscience,andhowitprogresses.Analyzingsomekeymilestonesinthehistoryofscience(suchastheCopernicanrevolution),Kuhnconcludedthatscientistsnormallyworkwithinacertainparadigm;theyareconservativeuptoapoint,anddonotabandontheirexistingtheorieseveninthefaceofsomeanomalies(disagreementwithexperiment).However,whentheanomaliesarestarkandaccumulatewithtime,thereisacrisisinnormalscience,andtheexistingparadigmisquestioned.Allkindsofalternativeideasfloatduringthecrisis,outofwhichsomepromisingnewideasbegintoattractconsensus,oftenbecauseofsomeparticularlystrikingexemplars.Anewparadigmisborn,andnormalsciencereturns,inwhichscientistsworkoutthedetailsandapplicationsofthechangedparadigm.
ThekeypointtonoteinKuhn’sphilosophyisthattheparadigmshiftisnotgovernedbyapurelyrationalprocess;itinvolvesasocialconsensusinthescientificcommunity.Theadherencetoanexistingparadigminnormalscienceissecuredthroughtraininginourcollegesandgraduateschools.NoteverybodyagreedwithKuhn.LakotosfoundtheunderminingoftherationalbasisofscientificprogressimpliedinKuhn’sideasunacceptable,anddevelopedhisowntheoryintermsofthenotionofcompeting‘researchprogrammes’.Feyerabenddismissedtheveryideathatthereisanyclearmethodinthewayscienceevolves.Hisphilosophyisoftensummarizedbythecatchyline:‘anythinggoes’.Hisnotedbook‘AgainstMethod’celebratescreativityinscienceandadvocatesfreedomofimagination.ThuswhileLakotosfoundthedisorderinherentinKuhn’sviewofsciencealarming,FeyerebendcriticizedKuhnforjusttheoppositereason--forhisorderlyandmechanicalviewofscientific
FrancisBacon'sworkestablishedtheScientificMethod
3736 REDISCOVERING SCHOOL SCIENCE
progress.NormalsciencehadaverysignificantroleinKuhn’sscheme,sinceitgoesdeepintoanacceptedparadigm,makingitpossibletodiscoveranomaliesthateventuallyresultinchangingtheparadigm.Feyerebend,ontheotherhand,criticizestheroutinemind-numbingactivitiesofnormalscience,andassertsthatscienceprogressesthroughcreativeleapsofimaginationthatdefyexistingideas.
WhateverthemeritsofKuhn’stheory,itwascertainlyresponsibleforintroducingasociologicaldimensiontophilosophyofscience,inthesecondhalfofthe20thcentury.Indeedsomesociologistsviewedthestandardphilosophyofscienceasirrelevant,andassertedthatwecanunderstandnatureofscienceonlybyacriticalanddetailedprobingoftheactualwayinwhichscientistswork.Thisdevelopmenthastakenthedebateonnatureofscienceinmanydifferentdirectionsthatwecannotadequatelydescribehere.But,wecertainlyhaveabetterperspectivenowonthesocio-culturalnormsthatenablesciencetogrow.Forexample,itseemsclearthattheformationofrobustsocialinstitutionsofscience(ScientificSocietiesinEurope,suchastheRoyalSociety)practisingnormsofopenanddemocraticdiscussion,peerreviewingofresearch,andcommunalownershipofscientificlaws,etc.wasascrucialforthegrowthofscience,astheingenuityofindividualscientists.
Wecansummarisesomenewinsightsonnatureofsciencethathavegraduallyemergedfromthesediscourses.First,scienceisnotjustinductionfromobservationsandexperimentaldata;itofteninvolvesimaginativeandradicalnewideasnotnecessarilysuggestedbythem.Forexample,someofthemostsuccessfultheoriesofsciencehavearisenfromgeneralconsiderationsofsimplicityandsymmetry,andadriveforunification.Second,thoughobservationsofnatureareoftenthestartingpoint,notallobservationsareneutral-theyare‘theory-laden’;theories,implicitlyorexplicitly,guideustowhereandwhattoexperimentandobserve(thisdoesnotnecessarilyunderminetheobjectivityofscience).
Third,observationsandexperimentaldataunderdeterminecorrecttheory;severaldifferenttheoriescanallbeconsistentwiththem.Fourth,scienceisnotapurelycognitiveendeavour;thoughitiscertainlyconstrainedbytheempiricalfactsofnature,italsoinvolvessomesocialconsensusamongscientistsandneedsenablingsocio-culturalnormsandconditionsforits
growth.Fifth,science,technologyandsociety(STS)areintertwinedincomplexways,affectingandbeingaffectedbyoneanother.Acorollaryofthelastpointisthatwemustbealerttothepossiblepitfallsinscientificpracticeandtheharmfulconsequencesofuncriticalandunwiseuseoftechnology.
Thisbriefoverviewisintendedonlytogiveaflavourofthesubject;itadmittedlydoesnotcapturethemanysubtleaspectsofphilosophyofscience.See,forexample,Godfrey-Smith(2003)¹foradeepertreatmentofthissubject,andforreferencesoftheclassicworksmentionedabove.
Natureofscience:howandwhattoteach
Withsomuchofthehistoricaldebateonnatureofsciencecontinuingintothepresent,whatisitthatwewishstudentstolearnaboutNOSinschooleducation?Obviously,wecannotimportthecomplexphilosophicalissuesonthematterintoourclassrooms.Therehasbeenmuchreflectiononthispoint,andthefeelingisthatdespitethewiderangeofperspectives,thereisacoreofgenerallyacceptednewideasinNOSthatarelearnablebyyoungstudents.WerecommendreferringtotheNewGenerationScienceStandardsNGSS(2013)²developedintheU.S.A.Ofcourse,similarobjectiveshavebeenadvocatedelsewhere;see,forexample,Pumfrey(1991)³,Osborneetal(2002)⁴;andalsoTaylorandHunt(2014)⁵.Foramuchdeeperperspectiveonthesubject,seeErduranandDagher(2014)⁶.Wesummarize,here,whatinourviewappearstobeabroadconsensus;moredetailsonNOSobjectivescanbefoundinthereferencescited.
NatureofScienceObjectives(Summary)
Studentsshouldappreciatethat…
Scope
…Scienceseekstodescribeandexplainthephysicalworldbasedonempiricalevidence.Somedomainsmaybebeyonditsscope.
Methods
…Scienceadoptsavarietyofapproachesandmethods;thereisnooneuniversalmethodofscience.
Sciencedoesnotinvolveinductiononly.Creativityandimaginationareequallyimportantingeneratinghypothesesandbuildingtheories.
Observationsandexperimentsareofteninsufficienttodetermineatheory.
Scienceinvolvesexpertjudgements,andnotjustlogicaldeductions.Hencetherecanbedisagreement.
Socialaspects
…Scienceisaco-operativemulti-culturalhumanenterprisetowhichcountlessmenandwomencontribute,includingsomenotedindividualswhoplayasignificantrole.Socialinstitutionspractisingnormsofopendebate,peerreviewingandcommonownershipofknowledgearevitalforitsgrowth.
Scienceandtechnologymayleadtoissuesthatneedsocio-culturalresolution.
Scientificknowledge
…isdynamicandsubjecttorevisionbynewempiricalevidence.
Finally,themostimportantbutdifficultquestion:whatpedagogyistobeemployedtoteachNOS?Theideathatcontentaloneisnotenoughinscienceeducationisnotnew,asthehistoryofcurriculumreformssincethe1960s(orevenearlier)shows.Aroundthe1970s,someeducationalreformsemphasizedprocessesofsciencemorethanitscontent:observing,measuring,classifying,analysing,inferring,interpreting,experimenting,predicting,communicating,etc.Soontherewerecriticalappraisalsofthisapproach;someeducatorsquestionedtheverypremisethatthereareasetofgeneraltransferableprocessescommontoallsciences.See,forexample,MillarandDriver(1987)⁷.Forsometimenow,thereseemstobeabroadconvergenceonanInquiry-basedapproachtosciencelearningandteaching.Thisapproach,informedbytheconstructivistphilosophy,nodoubt,involveslearningtheprocessesofsciencementionedabove;butitgoesmuchfurther,toincludeposingquestions,criticalthinking,givingevidence-basedexplanation,justifyingit,andconnectingittoexistingscientificknowledge,etc.Basically,thisapproachadvocatesthelearningofscienceinamannerthatresemblesthewayscientistscarryouttheirinvestigations.
Inquirytasksarenaturallyrelativelysimpleforyoungerchildren,andquiteelaborateforthe
morematurestudents,buttheysharethecommonfeatureof
posingaquestionandseekinganevidence-basedexplanation.Theycanhavedifferentfoci;somemayrelatetoSTSissues,whileothersmaybemorediscipline-oriented.Inquirymayalsoincludereflectionsontheinquirymodeitself,andthusnaturallyincorporateNOS
educationalobjectives.Wereferthereadertoacritical
accountoftheInquiryapproach,includingitsrelation
withNOS,inFlickandLederman(2006)⁸.
AnotherapproachusestheHistoryofScience(HOS)asameanstoteachNOS.Thisagainisnotanewidea;seetheexcellentbookbyHoltonandBrush(2001)⁹.Somekeypointsinitsfavourarethoughttobe:HOSinvolveshumannarrativeswhichenlivenscienceandengagestudents’interest;itoftenhasparallelswithstudents’spontaneousconceptionsandthushelpsusinanticipatingandremedyingtheircontent-specificideas;knowinghowpresentsciencearosefromcompetingideasatdifferenttimesinhistorycanpromotecriticalthinking;andlastly,HOSisthemostnaturalsettingforlearningNOS.WereferthereadertoacomprehensiveHandbookbroughtoutrecentlyonthisissue(Matthews2014)¹⁰.
AsLederman(2006)¹¹hasforcefullyargued,NOSobjectivesshouldberegardedasprimarilycognitiveoutcomesthatcanbeproperlyassessed.Instructionneedstobringthemoutexplicitly,theyareunlikelytobeassimilatedimplicitly,whetherweadoptanInquiryoraHistorybasedapproach.AwholerangeofinquirytasksandHOSbasedvignettes,explicitlyfocussedonNOS;needtobedevelopedifweaimtoimprovestudentunderstandingofnatureofscience.
Acknowledgements
ItisapleasuretothankJ.Ramadas,S.ChunawalaandK.SubramaniamofHBCSE(TIFR)aswellastheanonymousreviewersforgoingthroughthearticlecritically,andofferingusefulcommentsforitsimprovement.
3736 REDISCOVERING SCHOOL SCIENCE
progress.NormalsciencehadaverysignificantroleinKuhn’sscheme,sinceitgoesdeepintoanacceptedparadigm,makingitpossibletodiscoveranomaliesthateventuallyresultinchangingtheparadigm.Feyerebend,ontheotherhand,criticizestheroutinemind-numbingactivitiesofnormalscience,andassertsthatscienceprogressesthroughcreativeleapsofimaginationthatdefyexistingideas.
WhateverthemeritsofKuhn’stheory,itwascertainlyresponsibleforintroducingasociologicaldimensiontophilosophyofscience,inthesecondhalfofthe20thcentury.Indeedsomesociologistsviewedthestandardphilosophyofscienceasirrelevant,andassertedthatwecanunderstandnatureofscienceonlybyacriticalanddetailedprobingoftheactualwayinwhichscientistswork.Thisdevelopmenthastakenthedebateonnatureofscienceinmanydifferentdirectionsthatwecannotadequatelydescribehere.But,wecertainlyhaveabetterperspectivenowonthesocio-culturalnormsthatenablesciencetogrow.Forexample,itseemsclearthattheformationofrobustsocialinstitutionsofscience(ScientificSocietiesinEurope,suchastheRoyalSociety)practisingnormsofopenanddemocraticdiscussion,peerreviewingofresearch,andcommunalownershipofscientificlaws,etc.wasascrucialforthegrowthofscience,astheingenuityofindividualscientists.
Wecansummarisesomenewinsightsonnatureofsciencethathavegraduallyemergedfromthesediscourses.First,scienceisnotjustinductionfromobservationsandexperimentaldata;itofteninvolvesimaginativeandradicalnewideasnotnecessarilysuggestedbythem.Forexample,someofthemostsuccessfultheoriesofsciencehavearisenfromgeneralconsiderationsofsimplicityandsymmetry,andadriveforunification.Second,thoughobservationsofnatureareoftenthestartingpoint,notallobservationsareneutral-theyare‘theory-laden’;theories,implicitlyorexplicitly,guideustowhereandwhattoexperimentandobserve(thisdoesnotnecessarilyunderminetheobjectivityofscience).
Third,observationsandexperimentaldataunderdeterminecorrecttheory;severaldifferenttheoriescanallbeconsistentwiththem.Fourth,scienceisnotapurelycognitiveendeavour;thoughitiscertainlyconstrainedbytheempiricalfactsofnature,italsoinvolvessomesocialconsensusamongscientistsandneedsenablingsocio-culturalnormsandconditionsforits
growth.Fifth,science,technologyandsociety(STS)areintertwinedincomplexways,affectingandbeingaffectedbyoneanother.Acorollaryofthelastpointisthatwemustbealerttothepossiblepitfallsinscientificpracticeandtheharmfulconsequencesofuncriticalandunwiseuseoftechnology.
Thisbriefoverviewisintendedonlytogiveaflavourofthesubject;itadmittedlydoesnotcapturethemanysubtleaspectsofphilosophyofscience.See,forexample,Godfrey-Smith(2003)¹foradeepertreatmentofthissubject,andforreferencesoftheclassicworksmentionedabove.
Natureofscience:howandwhattoteach
Withsomuchofthehistoricaldebateonnatureofsciencecontinuingintothepresent,whatisitthatwewishstudentstolearnaboutNOSinschooleducation?Obviously,wecannotimportthecomplexphilosophicalissuesonthematterintoourclassrooms.Therehasbeenmuchreflectiononthispoint,andthefeelingisthatdespitethewiderangeofperspectives,thereisacoreofgenerallyacceptednewideasinNOSthatarelearnablebyyoungstudents.WerecommendreferringtotheNewGenerationScienceStandardsNGSS(2013)²developedintheU.S.A.Ofcourse,similarobjectiveshavebeenadvocatedelsewhere;see,forexample,Pumfrey(1991)³,Osborneetal(2002)⁴;andalsoTaylorandHunt(2014)⁵.Foramuchdeeperperspectiveonthesubject,seeErduranandDagher(2014)⁶.Wesummarize,here,whatinourviewappearstobeabroadconsensus;moredetailsonNOSobjectivescanbefoundinthereferencescited.
NatureofScienceObjectives(Summary)
Studentsshouldappreciatethat…
Scope
…Scienceseekstodescribeandexplainthephysicalworldbasedonempiricalevidence.Somedomainsmaybebeyonditsscope.
Methods
…Scienceadoptsavarietyofapproachesandmethods;thereisnooneuniversalmethodofscience.
Sciencedoesnotinvolveinductiononly.Creativityandimaginationareequallyimportantingeneratinghypothesesandbuildingtheories.
Observationsandexperimentsareofteninsufficienttodetermineatheory.
Scienceinvolvesexpertjudgements,andnotjustlogicaldeductions.Hencetherecanbedisagreement.
Socialaspects
…Scienceisaco-operativemulti-culturalhumanenterprisetowhichcountlessmenandwomencontribute,includingsomenotedindividualswhoplayasignificantrole.Socialinstitutionspractisingnormsofopendebate,peerreviewingandcommonownershipofknowledgearevitalforitsgrowth.
Scienceandtechnologymayleadtoissuesthatneedsocio-culturalresolution.
Scientificknowledge
…isdynamicandsubjecttorevisionbynewempiricalevidence.
Finally,themostimportantbutdifficultquestion:whatpedagogyistobeemployedtoteachNOS?Theideathatcontentaloneisnotenoughinscienceeducationisnotnew,asthehistoryofcurriculumreformssincethe1960s(orevenearlier)shows.Aroundthe1970s,someeducationalreformsemphasizedprocessesofsciencemorethanitscontent:observing,measuring,classifying,analysing,inferring,interpreting,experimenting,predicting,communicating,etc.Soontherewerecriticalappraisalsofthisapproach;someeducatorsquestionedtheverypremisethatthereareasetofgeneraltransferableprocessescommontoallsciences.See,forexample,MillarandDriver(1987)⁷.Forsometimenow,thereseemstobeabroadconvergenceonanInquiry-basedapproachtosciencelearningandteaching.Thisapproach,informedbytheconstructivistphilosophy,nodoubt,involveslearningtheprocessesofsciencementionedabove;butitgoesmuchfurther,toincludeposingquestions,criticalthinking,givingevidence-basedexplanation,justifyingit,andconnectingittoexistingscientificknowledge,etc.Basically,thisapproachadvocatesthelearningofscienceinamannerthatresemblesthewayscientistscarryouttheirinvestigations.
Inquirytasksarenaturallyrelativelysimpleforyoungerchildren,andquiteelaborateforthe
morematurestudents,buttheysharethecommonfeatureof
posingaquestionandseekinganevidence-basedexplanation.Theycanhavedifferentfoci;somemayrelatetoSTSissues,whileothersmaybemorediscipline-oriented.Inquirymayalsoincludereflectionsontheinquirymodeitself,andthusnaturallyincorporateNOS
educationalobjectives.Wereferthereadertoacritical
accountoftheInquiryapproach,includingitsrelation
withNOS,inFlickandLederman(2006)⁸.
AnotherapproachusestheHistoryofScience(HOS)asameanstoteachNOS.Thisagainisnotanewidea;seetheexcellentbookbyHoltonandBrush(2001)⁹.Somekeypointsinitsfavourarethoughttobe:HOSinvolveshumannarrativeswhichenlivenscienceandengagestudents’interest;itoftenhasparallelswithstudents’spontaneousconceptionsandthushelpsusinanticipatingandremedyingtheircontent-specificideas;knowinghowpresentsciencearosefromcompetingideasatdifferenttimesinhistorycanpromotecriticalthinking;andlastly,HOSisthemostnaturalsettingforlearningNOS.WereferthereadertoacomprehensiveHandbookbroughtoutrecentlyonthisissue(Matthews2014)¹⁰.
AsLederman(2006)¹¹hasforcefullyargued,NOSobjectivesshouldberegardedasprimarilycognitiveoutcomesthatcanbeproperlyassessed.Instructionneedstobringthemoutexplicitly,theyareunlikelytobeassimilatedimplicitly,whetherweadoptanInquiryoraHistorybasedapproach.AwholerangeofinquirytasksandHOSbasedvignettes,explicitlyfocussedonNOS;needtobedevelopedifweaimtoimprovestudentunderstandingofnatureofscience.
Acknowledgements
ItisapleasuretothankJ.Ramadas,S.ChunawalaandK.SubramaniamofHBCSE(TIFR)aswellastheanonymousreviewersforgoingthroughthearticlecritically,andofferingusefulcommentsforitsimprovement.
3738 REDISCOVERING SCHOOL SCIENCE
Contributedby:GeethaIyer.Source:Reproduced,withpermission,fromTheScienceEducationReview,Volume3(2004),pp.111-112.www.scienceeducationreview.com
GeethaIyerisanindependentconsultant,workingwithseveralschoolsincurriculumdesignaswellasScience&Environmenteducation.ShewaspreviouslyateacherattheRishiValleySchool,andthen,theHeadofSahyadriSchool(KFI),nearPune.Shehaswrittenextensivelyontopicsineducationandtheenvironment.Shecanbereachedatscopsowl@gmail.com.
References
1.IntroductiontoPhilosophyofScience.Godfrey-SmithP.(2003).Chicago.TheUniversityofChicagoPress.
2.Nextgenerationsciencestandards:Forstates,bystates.NGSS(2013).AppendixHwww.nextgenscience.org
3.HistoryofscienceintheNationalScienceCurriculum:acriticalreviewofresourcesandtheiraims.Pumfrey,S.(1991).BritishJournaloftheHistoryofScience.24,61–78.
4.EPSEProject3Teachingpupils‘ideas-about-science’.Osborne,J.,Ratcliffe,M.,Bartholomew,H.,Collins,S.&Duschl,R.(2002b).SchoolScienceReview,84(307),29–33.
5.HistoryandPhilosophyofScienceandtheTeachingofScienceinEngland.TaylorJ.L.andHuntA.(2014).MatthewsM.R.(ed.)op.cit.2045-2082.
6.ReconceptualizingtheNatureofScienceforScienceEducation.ErduranS.&DagherZ.R(2014).Dordrecht,Netherlands.Springer.
7.Beyondprocesses.Millar,R.&Driver,R.(1987).StudiesinScienceEducation,(14)33–62.
8.ScientificInquiryandNatureofScience.FlickL.B.andLedermanN.G.(eds.)(2006).Dordrecht,Netherlands.Springer.
9.Physics,theHumanAdventure.HoltonG.andBrushS.G.3rded.(2001).NewBrunswick.NJ.RutgersUniversityPress.
10.InternationalHandbookofResearchinHistory,PhilosophyandScienceTeaching.MatthewsM.R.(ed.)(2014).Dordrecht,Netherlands.Springer.
11.SyntaxofNatureofSciencewithinInquiryandScienceInstruction.LedermanN.G.(2006).InFlickL.B.andLedermanN.G.(eds.)(2006)op.cit,301-317.
ArvindKumar,formerlyattheHomiBhabhaCentreforScienceEducation(TataInstituteofFundamentalResearch),Mumbai,nowteachesattheCentreforBasicSciences,Mumbai.Hismainacademicinterestsaretheoreticalphysics,physicseducation,andtheroleofhistoryandphilosophyofscienceinscienceteaching.Theauthorcanbecontactedatarvindk@hbcse.tifr.res.in
Flatus is the gas generated in, or expelled from, the
digestive tract, especially the stomach and intestines. More than 99% of human flatus comprises nitrogen, oxygen, hydrogen (hydrogen-consuming bacteria in the digestive tract may consume some of this to produce methane and other gases), carbon dioxide, and methane.
During World War II, US fighter pilots flew at increasing altitudes. The associated reduction in the (external) atmospheric pressure allowed the digestive gases trapped in
their intestines to expand (Boyle’s law), causing very painful cramps. Foods known for their ability to produce flatus – dried beans and peas, vegetables of the cabbage family, carbonated drinks, and beer – were therefore removed from pilots’ menus.
Methane is a combustible gas (e.g. a good fuel for Bunsen
burners), although it is produced by only about one-third of people in the Western world. In the early days of the space race, there was some concern that the methane emitted by astronauts, if accidentally ignited, could cause an explosion within the spacecraft. No such incidents have occurred to date. However, exploding flatus has caused the accidental death of at least one surgical patient. An electrode touched to the patient’s colon ignited the hydrogen and methane it contained, also causing the surgeon to be blown back to the wall of the room.
Flatus: Beware!Flatus: Beware!
