Role of Experiments in the Progress of Science aset · ancient Indian metallurgists. The Delhi...

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RoleofExperimentsintheProgressofScience:LessonsfromourHistory

Ishalldiscussthehistoryof IndianAstronomy,Ayurveda,Chemistry andMetallurgy to illustrate how downgradingexperimentsfromscientificlearningleadtothedeclineofancientIndianscienceandcivilization.

D.P.RoyHomiBhabhaCentreforScienceEducation(TIFR)

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In his address as the Sectional President in Physics andMathematicsof the IndiannationalScienceCongress (1926)MeghnadSahaquotedthefollowinglinesfroma9thcenturySanskrit text on Chemistry, called ‘Rasendra Chintamani’ byDhunduknath,broughttohisnoticebyhisteacherP.C.Ray:

• Ihaveheardmuchfromthelipsofsavants,Ihaveseenmanyformulaewell-establishedinscriptures,butIamnotrecordinganywhich I have not donemyself. I am fearlessly recordingonly those that I have carriedoutbeforemyelderswithmyownhand.Onlytheyaretoberegardedasrealteacherswhocan show by experiments what they teach. They are thedeservingpupilswhocanactuallyperformthemafterhavinglearnedfromtheirteachers.Therestaremerelystageactors.

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IndianChemistryafterthe9thCentury:P.C.Ray(HistoryofChemistryinAncient&MedievalIndia)

• Indianchemistrycontinuedtodevelopforafewcenturiesafterthismainlyastheempiricalscienceofalchemy.

• Alchemywaspracticedbymenregardlessofcaste,butshunnedbyBrahmins.

• Thereweremanypioneersinalchemy;andanoutstandingfigurenamedNagarjunahasbeenrespectfullyreferredinAlBeruni’sIndiaofearly11

thcentury

tohavelivedacenturyearlier.(ButthereareseveralNagarjunasinhistory?)

• AlchemywastaughtinNalanda,Vikramshila&Udantapuramonasteriestilltheirdestructionaround1200AD.

• AfterthisthealchemistsfledtoTibetandDeccan.

• P.C.RaytracesbackthedevelopmentofchemistryinIndiatothissubalterncultureofalchemy.

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ReviewoftheIndiancalendarReformsCommitteeunderM.N.SahaonthethreeperiodsofancientIndianAstronomy: Vedic(->1300BC),Vedanga(1300BC-400AD),Siddhanta(400-900AD)

• DuringtheVedangaperiodemphasishadshiftedfromcollectingobserveddatatoachievingmorecomputationalprecision.TheSakasandKusanasbroughtthecontemporaneousknowledgeofAstronomyfromBactriatonorth-westIndia.ThislatestexposureinitiatedthegreatspurtofactivitiesintheSiddhantaera.SuryaSiddhantaisassignedto3rdcenturyAD,followedbyblazingluminaries:Aryabhatta&Varahamihira(500AD),Brahmagupta&BhaskaraI(600AD).AryabhattaauthoredAryabhatiyaandarevisedversionofSuryaSiddhanta.HealsohadaprofoundinfluenceonthedevelopmentofIslamicAstronomy.Sotherewasatwo-wayinteractionwithothercivilizations.

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ScientificInfluencefromotherCivilizations(Wikipedia)

• TheYavanajatakawastranslatedfromGreektoSanskritbyYavanesvaraduring2ndcenturyADunderSakakingRudradaman.HiscapitalUjjainwasthe“GreenwichofIndianAstronomy”.

• Laterinthe6thcentury,RomakaSiddhantaandPaulisaSiddhantawere2ofthe5maintreatisesofVarahamihiracalledPancha-Siddhanta.

• Hewrote“TheGreeks,thoughimpure,mustbehonouredsincetheyweretrainedinsciencesandthereinexcelledothers”.Gargi-Samhitasays“TheYavanasarebarbarians,yetthescienceofAstronomyoriginatedwiththemandforthistheymustbereveredlikeGods”.

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ScientificInfluenceonotherCivilizations(Wikipedia)

· IndianAstronomyreachedChinawiththeexpansionofBuddhismduringHandynasty(25-220AD).FurthertranslationofIndianworksonAstronomywascompletedinChinaduringtheThreeKingdomsera(220-265AD).However,mostdetailedincorporationofIndianAstronomyoccurredonlyduringtheTangdynasty(618-907AD).

• Arabsadoptedthesinefunction(inheritedfromIndianmathematics)insteadofchordsofarcusedinHellenisticmathematics.AnotherIndianinfluencewasanapproximateformulausedfortimekeepingbyMuslimastronomers.IndianAstronomyhadaninfluenceonEuropeanAstronomyviaArabictranslations.

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DeclineofSiddhantaAstronomyafter900AD:BhaskaraII(12thcent.),KeralaSchool(15-16thcent),

SamantaChandraSekhar(19thcent.)

• ThelastexponentofSiddhantaAstronomy,SamataChandraSekhar,livedinOrissafrom1835to1904.Heconstructedhisowninstruments,acquiredgreatskillinusingthemforaccurateobservationsofsun,moon,planetsandstars.WhenhefoundbyrepeatedobservationsthatthemeasuredpositionsinmostcasesdonotagreewithresultscomputedusingthefamousSiddhantas,heboldlyconcludedthatthelatterareinerror,nothisexperimentaldeterminations.HewrotehisfindingsinSiddhantaDarpanaonpalmleavesinSanskritusingOriyascript.Prof.J.C.RayofRavenshawCollege,Cuttack,arrangedtopublishitinDevanagariscriptthroughaCalcuttapressthirtyyearslater,in1899.

–Prof.M.K.Pal

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Determinationofthe4CardinalPoints(Wikipedia):SummerandWinterSolstice(MakarSamkranti),AutumnandVernalEquinox(VishuvSamkranti).

• ThesimplestdeviceusedinastronomywasGnomon,calledSanku,inwhichthedirectionandlengthoftheshadowofaverticalrodweremeasuredtofindthecardinaldirections,thelatitudeandtime.

• Inthetropicalregion,the2daysofthelongestmiddayshadowsalongnorthandsouthmarkwinterandsummersolsticesrespectively.

• The2midpointsofthesummerandwintersolsticesmarkthe2equinoxes.

• Atthetimeofthiscalibrationaround500AD,theHelial(Sunsynchronous)risingoftheconstellationCapricorn(Makar)correspondedtowintersolsticeday(MakarSamkranti).

• Butprecessionofearth’srotationaxishasresultedina23daysgapbetweentheseterrestrialandcelestialmarkersoverthepast1500years!

• Thisisaglaringexampleofhowblindfollowingoftextwithoutexperimentalrecalibrationleadstowrongsolsticeandequinoxtimes.

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Minimumshadowlengthmarksmid-day.

Largestmid-dayshadowlengthalongnorth(south)markswinter(summer)Solstice.

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MayankVahiaDNA,9March2014

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Non-recordingofpurelyEmpiricalPhenomenainIndianAstronomicalTexts

• TheChinesehavekeptdataofmeteoricshowers,29appearancesofHalley’scomet,90novaeandsupernovaeandintensesunspotactivities.

• YetthereisnoIndianrecordofthesepurelyempiricalphenomena.

• InparticularthespectacularCrabsupernovaexplosionof11thcenturyappearedasthe2ndbrightestobjectofnightskyafterthemoonforseveralweeks.ItisrecordedbyChinese,ArabandevenMayanastronomersofMexico.

• YetthereisnocredibleevidenceofIndianastronomicalrecordofthisevent,presumablybecauseitwasnotamenabletoanytheoreticalexplanationatthattime.

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AncientIndianMetallurgy-Wikipedia

IndiawasamajorexporterofFerrousmetalsthroughoutancientHistory.IronPillarsofDelhi/Vidisha(400AD),andDhar(1000AD)standlivingtestimonytotheskillsofancientIndianmetallurgists.TheDelhipillaris7mhighandweighs6.5tons.Itis98%pureIronwithahighPhosphorouscontenttomakeitrust-free.NoothercountryhadthecapabilitytoproduceanironmassofthissizeandpuritytilltheIndustrialRevolutionof18thcentury.

ProductionofsteelbycarbonizationofironoriginatedinDeccanaround600BCandgloballyexportedthroughoutthisperiod.

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Metallurgyafter1000AD B.Prakash:Ind.J.ofHistoryofScience(2011)

• Ghaznavid&Ghorianinvasionsduring11th-12thcenturiesdestroyedtheIndianironindustryandtookawaymanythousandsofskilledmetalworkersasslavestobolstertheirownarmamentproduction.

• DuringtheMughalperiod,however,asubalterncultureofironmetallurgywasrevivedforlargescaleproductionofarmamentsandconstructionofverylargecannons.

• DeccansteelexporttotheArabcountriesformakingqualityarmaments(famousDamascusswords)continued.

• Bothofthesedeclinedtowardstheendof17thcentury.

• IndianmetalindustrydiedfollowingtheBIGovt.policyofshippingironoretoBritishironmillsatthecostoftheIndianfoundries.

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AurvedicBiology–M.S.Valiathan

• TheSamhitaphasefrom1stto8thcenturyADisgenerallyregardedasthegoldenageofAyurveda.

• IthadthreemajortextscalledtheBrihadtrayi.

• CarakaSamhita(1stcent.)isaredactionbyCarakaofatreatisecomposedbyAgnivesseveralcenturiesearlier.

• SusrutaSamhita(2nd-3rdcent.)isaredactionbyNagarjunaofthesurgicaltreatiseofSusruta,whoissaidtohavelivedaround700BC!

• AstangaSamgraha&AstangaHrdaya(8th-9thcent.)arecomposedbyVagbhata.

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CharakaSamhita(1stcenturyAD)

• Caraka’sredactionwassohighlycreativethatthenewtextwasacclaimedasCarakaSamhita.

• HereAyurvedagotitsnameforthefirsttime,anditmovedfromafaith-basedtoareasonbasedplatform.

• Itwasencyclopedicinthecoverageofmedicines,andrecognizedasthelastwordininternalmedicine.

• ItwastranslatedintoPersian,ArabicandTibetanwithin2-3centuriesandspreaditsinfluencetocentralAsia,whereBowerManuscriptof400ADwithnumerousquotesfromCarakawasdiscoveredin1890.

• ItwastranslatedintoEnglishin19thcentury.

• Itspopularitycontinuesinthe21stcentury,whenadigitalversionwas

preparedbyProf.YamashitaofKyotoUniv.

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SusrutaSamhita(3rd-4thcenturyAD)

• Susruta’snameisforeverassociatedwithRhinoplasty(noserepair),theonlysurgicalprocedurefromIndiatohavewonglobalrecognitionin3millennia!

• SusrutaSamhitaisacomprehensivemedicaltreatisewithheavysurgicalorientation,dealingwithsurgicalprocedures,instruments,careoftrauma,medicationsetc.

• ComparedtoCarakaSamhitaithassimplerlanguageandloweremphasisonthephilosophicaldimensionsofmedicalpractice.

• SusrutaSamhitaenjoyedgreatauthorityevenbeyondIndianbordersbecauseitwastranslatedintoArabicundertheCaliphate,whenIndianphysicianswerebelievedtohavelivedinBaghdad.

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SusrutaandCarakSamhitas(cont.)

• ThereislittledoubtthattheSusrutaandCarakSamhitasweretaughtatNalanda;andthelargenumberofstudentsfromTibet,ChinaandothercountriesofEastAsiawouldhavecarriedhometheircopiesandtranslations.

• TransferofknowledgewasalsofacilitatedbyIndianteachersaccompanyingthesehome-bounddisciples.

• Eventodayseveraltextsinmedicine,philosophyetc,whicharenolongeravailableintheSanskritoriginal,areavailableintheirChineseandTibetantranslations.

• WhatthebarbariansdestroyedinIndiahadaresurrectioninothercountries.(DestructionofNalanda,VikramshilaandUdantapurabyBakhtiarKhilziin1200AD)

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AstangaSamgraha&AstangaHrdaya(Vagbhata)

• AcharyaP.C.Rayestimatedthedateofcompositionofthesetextstobe8th–

9thcentury,whenAyurvedawasonthethresholdofStagnation.

• ThetextsacceptstheauthorityofCarakaandSusrutainnouncertaintermsandpresenttheirteachingsinasimpleandabridgedmannerforaveragestudents.

• AstangaHrdayaaccomplishedthisobjectiveadmirablyandbecameapopularfavourite,thankstothegiftofpoeticexcellencethatnoothertextcouldclaim.

• AfterVagbhata,thespringsofcreativityrandryandalongphaseofstagnationensuedforathousandyearsinthehistoryofAyurveda.

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StagnantPhaseofAyurveda(10thcent.->)

• TherewerenomoreCarakasandSusrutas,northeadventofpower-housesoflearninglikeNalandainthisphase.

• MuslimrulerspreferredUnanioverAyurveda.

• ButthemaladyhadrootsdeeperinthesocialhistoryofIndia,becausethesurgicaltechniquesofSusrutahadmoreorlessdisappearedfromthemainstreamofAyurvedaalreadybythetimeofVagbhata.

• Cadavericdissectionswasnomorementioned;andthetrainingofdisciplesdidnotincludeexercisesoncucumber,jackfruit,animalskinetcforlearningincision,extraction,scrapingandothersurgicalprocedures.

• SoMuslimconquestofIndiaanddestructionofNalandain1200ADwerenotthecausesbuttheconsequencesofthedeclineofIndianscienceandcivilization.

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Alberuni’sIndia(1000AD)

• TheHindusbelievethatthereisnocountrybuttheirs,nonationliketheirs,nokingliketheirs,noreligionliketheirs,noscienceliketheirs.

• Theyarehaughty,foolishlyvain,self-conceited,andstolid.

• Theyarebynatureniggardlyincommunicatingthatwhichtheyknow,andtheytakethegreatestpossiblecaretowithholditfrommenofanothercasteamongtheirownpeople,stillmuchmore,ofcourse,fromanyforeigner.

• Theirhaughtinessissuchthat,ifyoutellthemofanyscienceorscholarinKhorasanorPersia,theywillthinkyoutobebothanignoramusandaliar.

• Iftheytraveledandmixedwithothernations,theywouldsoonchangetheirmind,fortheirancestorswerenotasnarrow-minedasthepresentgenerationis.

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SubcultureofSurgicalSkillsinLowercastesValiathan

• Thesurgicalprocedurethatdisappearedfromthemainstreamsurfacedhoweveramongcastes,whichwerelowinthesocialhierarchy.

• Susruta’snoserepairisaninterestingexample.

• Barringaperfunctoryreference,itreceivednoseriousattentionintheAurvedictexts;norwasitperformedbyreputedVaidyas.

• Itssurvivalwas“discovered”accidentallybyBritishobserversinPunetowardstheendof18thcentury.

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Punenoserepairepisode

• Dr.Scott,asympatheticBritishdoctorresidinginMumbai,hadheardfromoneCapt.Irvinein1793aboutthepracticeamong“gentoosofputtingnewnosesonpeoplewhohavehadthemcutoff”!

• HeassuredDr.ScottthatalltheemployeesoftheEastIndiaCompanyinPunewerewitnessestotheoperationwhichgavethemana“prettygoodnose”.

• Dr.ScottwrotetoMr.Findlay,thecompanysurgeoninPune,toascertaintheveracityofthisreportbecausesuchanoperationwasunknowninEurope.

• Mr.FindleysentadetailedreportonthebasisofeyewitnessobservationbyhimselfandMr.Crusoon1stJanuary1794.

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• Thereportdescribedhowa“koomar”castemanhadborrowedanoldrazorfortheoccasion,dissectedaflapfromtheforeheadofthepatientwithmuchcomposure,freshenedtheedgesofthenasaldefectandappliedtheflapthereonbyrotationwithacement“withouttheaidofstitches,stickingplasterorbandages”.Theflaphealedand“anadhesionhastakenplaceseeminglyineverypart”.

• Itwasareportofthisprocedure,publishedinthe“Gentleman’sMagazine”ofLondonin1794,whichcaughttheattentionofasurgeon,Dr.J.C.Carpue,FRS.

• Heperformedtheoperationforthe1sttimeintheWestandpublishedafulllengthpaperon“Anaccountoftwosuccessfuloperationsforrestoringalostnosefromtheintegumentsoftheforehead”in1816(H.Scott,Bombay,IndiaOfficeLibrary,London).

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• AsimilareyewitnessreportonSusruta’scouchingforcataractwasgivenbyDr.EkambaramofCoimbatorein1910.HefoundthattheprocedurewasdonebyitinerantMohammedanvaidyaswhofollowedthestepsofSusruta’smethod.

• NotethattheprocedureinPuneandCoimbatoreweredonenotbyAyurvedicphysiciansbutbyilliteratemen,whohadlearnedthetechniquesfromanearliergeneration.

• Treatmentoffracturebybonesetters,childdeliverybydaisandmanyotherproceduresinvolving“dirtyingofhand”wererelegatedtolowercastepersons,whodidnotunderstandtheiranatomicalbasisorrationale.

• Itwasasifthenation’sbrainwasdecoupledfromitshand,whichensuredthattherecouldneverbeinnovationbasedontrueunderstanding.

OtherSurgicalSkills

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SubcultureofMetallurgicalSkillsinLowerCastesDharampal:IndianScience&Technologyinthe18thCentury

• OntherequestoftheGovt.ofBengalin1828,JamesFranklinFRS,madeathoroughstudyoftheore,charcoalandfurnacesusedbythenativesofCentralIndiaformakingiron.

• Hewrote“thesmeltingfurnaces,thoughcrudeinappearance,areneverthelessveryexactintheinteriorproportions,andithasoftensurprisedmetoseemenwhoareunquestionablyignorantoftheirprinciple,constructthemwithsuchprecision”.

• Hewentontodescribeindetailthegeometricalandpracticalconstructionofthefurnace,theconstructionanduseofbellows,constructionoftworefineriesforeachfurnace,modeofsmeltingandrefiningetc.

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• OngettingtheproductevaluatedattheSagarminthewrote”thebarironwasofthemostexcellentquality,possessingallthedesirablepropertiesofmalleability,ductilityatdifferenttemperaturesandoftenacityofwhichIthinkitcannotbesurpassedbythebestSwedishiron”.

• ThoughtheworkmencouldnotanswerFranklin’squestionsorexplaintheproceduresusedforhundredsofyearsbytheirforefathers,hecommentedthatthe“originalplanofthissingularfurnacemusthavebeentheworkofadvancedintelligence”.

• ActuallythiswastherelicofacivilizationthathadproducedtheironpillarsofDelhi/Vidishain400ADandDharin1000AD.

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ReflectionsofValiathan

• TheworkmendoingnoserepairinPune,cataractcouchinginCoimbatoreandoresmeltinginJabalpurwerecondemnedtoilliteracy,lowsocialstatus,poorself-esteemandlittlehopeofselfadvancement.

• Sincethisgrimprospectclaimedhundredsofthousandsofcitizens,whousedtheirhandstomakealiving,ruincouldbetheonlydestinationoftheirnation.

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ReflectionsofP.C.Ray(HistoryofChemistryinancientandmedievalIndia)

• AccordingtoSusruta,thedissectionofthedeadbodiesisindispensibletothestudentsofsurgery,andthishighauthoritylaysparticularstressonknowledgegainedfromexperimentsandobservations.ButManuwouldhavenoneofit.AccordingtoManu,theverytouchofcorpseisenoughtocontaminatethesacredpersonofaBrahmin.ThuswefindshortlyafterVagbhata,thehandlingofalancetwasdiscouragedandanatomyandsurgeryfelltodisuse.Theybecameforallpracticalpurposes,lostsciencesfortheHindus.Itwasconsideredequallyundignifiedtosweatawayatthemetalfurnaces.

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• Thesciencesbeingthusrelegatedtothelowercastes,andtheprofessionsmadehereditary,acertaindegreeoffineness,delicacyanddeftnessinmanipulationwasnodoubtsecured.Butthiswasaccomplishedataterriblecost.Theintellectualportionofthecommunitybeingthuswithdrawnfromactiveparticipationinthesesciences,thehowandwhyofphenomenon–thecoordinationofcauseandeffect–werelostsightof.Thespiritofenquirygraduallydiedoutamongthenation(naturallypronetospeculationandmetaphysicalsubtleties),andIndiaforoncebadeadieutoexperimentalandinductivesciences.HersoilwasmademorallyunfitforthebirthofaBoyle,aDescartes,oraNewton;andherverynamewasexpungedfromthemapofthescientificworldforatime.

• Underthesecircumstances,India’sroutattheEast-Westencounterofthe18thcenturywasaforegoneconclusion.

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