1. The history of science
The historyof science isthe studyof the developmentof science andscientificknowledge,including
boththe natural sciencesandsocial sciences.(The historyof the artsand humanitiesistermedasthe
historyof scholarship.) Science isabodyof empirical,theoretical,andpractical knowledgeaboutthe
natural world,producedbyscientistswhoemphasizethe observation,explanation,andpredictionof
real worldphenomena.Historiographyof science,incontrast,studiesthe methodsbywhichhistorians
studythe historyof science.
The Englishwordscientistisrelativelyrecent—firstcoinedbyWilliamWhewell inthe 19thcentury.[1]
Previously,people investigatingnature calledthemselves"natural philosophers".Whileempirical
investigationsof the natural worldhave beendescribedsince classical antiquity(forexample,byThales
and Aristotle),andscientificmethodhasbeenemployedsince the MiddleAges(forexample,byIbnal-
Haytham andRoger Bacon),modernscience began todevelopinthe earlymodernperiod,andin
particularinthe scientificrevolutionof 16th- and 17th-centuryEurope.[2] Traditionally,historiansof
science have definedscience sufficientlybroadlytoinclude those earlierinquiries.[3]
From the 18th centurythroughlate 20th century,the historyof science,especiallyof the physical and
biological sciences,wasoftenpresentedinaprogressive narrative inwhichtrue theoriesreplacedfalse
beliefs.[4] Some more recenthistoricalinterpretations,such asthose of Thomas Kuhn,tendtoportray
the historyof science indifferentterms,suchasthat of competingparadigmsorconceptual systemsina
widermatrix thatincludesintellectual,cultural,economicandpolitical themesoutside of science.[5]
Early cultures
In prehistorictimes,advice andknowledgewaspassedfromgenerationtogenerationinanoral
tradition.Forexample,the domesticationof maize foragriculturehasbeendatedtoabout9,000 years
ago insouthernMexico,before the development of writingsystems.[6][7][8] Similarly,archaeological
evidence indicatesthe developmentof astronomical knowledge inpreliterate societies.[9][10] The
developmentof writingenabledknowledgetobe storedandcommunicatedacrossgenerationswith
much greaterfidelity.
Many ancientcivilizationscollectedastronomical informationinasystematicmannerthroughsimple
observation.Thoughtheyhadnoknowledgeof the real physical structure of the planetsandstars,many
theoretical explanationswere proposed.Basicfactsabouthumanphysiologywere knowninsome
places,andalchemywaspracticedinseveral civilizations.[11][12] Considerable observationof
macroscopicfloraand faunawas alsoperformed.
Africa
AncientEgyptmade significantadvancesinastronomy,mathematicsandmedicine.[13] Their
developmentof geometrywasanecessaryoutgrowthof surveyingtopreservethe layoutand
ownershipof farmland,whichwasfloodedannuallybythe Nile river.The 3-4-5righttriangle andother
rulesof geometrywere usedtobuildrectilinearstructures,andthe postandlintel architecture of Egypt.
Egypt wasalsoa centerof alchemyresearchformuch of the Mediterranean.

2. The EdwinSmithpapyrusisone of the firstmedical documentsstill extant,andperhapsthe earliest
documentthatattemptsto describe andanalyse the brain:itmightbe seenasthe verybeginningsof
modernneuroscience.However,whileEgyptianmedicine hadsome effective practices,itwasnot
withoutitsineffective andsometimesharmful practices.Medical historiansbelievethatancient
Egyptianpharmacology,forexample,waslargelyineffective.[14] Nevertheless,itappliesthe following
componentstothe treatmentof disease:examination,diagnosis,treatment,andprognosis,[15] which
display strongparallelstothe basicempirical methodof science andaccordingtoG. E. R. Lloyd[16]
playedasignificantrole inthe developmentof thismethodology.The Eberspapyrus(c.1550 BC) also
containsevidence of traditional empiricism.
AncientNearEast
Furtherinformation:Babylonianastronomy,Babylonianmathematics,Babylonianmedicine,Egyptian
astronomy,Egyptianmathematics,andEgyptianmedicine
Mesopotamianclaytablet,492 BC. Writingallowedthe recordingof astronomicalinformation.
From theirbeginningsinSumer(nowIraq) around3500 BC, the Mesopotamianpeoplebegantoattempt
to recordsome observationsof the worldwithnumericaldata.Buttheirobservationsand
measurementswere seeminglytakenforpurposesotherthanforelucidatingscientificlaws.A concrete
instance of Pythagoras'lawwas recorded,asearlyas the 18th centuryBC: the Mesopotamiancuneiform
tabletPlimpton322 recordsa numberof Pythagoreantriplets(3,4,5) (5,12,13)....,dated1900 BC,
possiblymillenniabefore Pythagoras,butanabstract formulationof the Pythagoreantheoremwas
not.[17]
In Babylonianastronomy,recordsof the motionsof the stars,planets,andthe moonare lefton
thousandsof claytabletscreatedbyscribes.Eventoday,astronomical periodsidentifiedby
Mesopotamianproto-scientistsare still widelyusedinWesterncalendarssuchasthe solaryear and the
lunarmonth.Using these datatheydevelopedarithmetical methodstocompute the changinglengthof
daylightinthe course of the yearand to predictthe appearancesanddisappearancesof the Moonand
planetsandeclipsesof the SunandMoon. Onlya few astronomers'namesare known,suchasthat of
Kidinnu,aChaldeanastronomerandmathematician.Kiddinu'svalue forthe solaryearisinuse for
today'scalendars.Babylonianastronomywas"the firstandhighlysuccessful attemptatgivingarefined
mathematical descriptionof astronomical phenomena."Accordingtothe historianA.Aaboe,"all
subsequentvarietiesof scientificastronomy,inthe Hellenisticworld,inIndia,inIslam, andinthe
West—if notindeedall subsequentendeavourinthe exactsciences—dependuponBabylonian
astronomyindecisive andfundamental ways."[18]
Greco-Roman world
In Classical Antiquity,the inquiryintothe workingsof the universe tookplace bothininvestigations
aimedat suchpractical goalsas establishingareliablecalendarordetermininghow tocure a varietyof
illnessesandinthose abstractinvestigationsknownasnatural philosophy.The ancientpeoplewhoare
consideredthe firstscientistsmayhave thoughtof themselvesasnatural philosophers,aspractitioners

3. of a skilledprofession(forexample,physicians),orasfollowersof areligioustradition(forexample,
temple healers).
The earliestGreekphilosophers,knownasthe pre-Socratics,[19] providedcompetinganswerstothe
questionfoundinthe mythsof theirneighbors:"How didthe orderedcosmosinwhichwe live come to
be?"[20] The pre-SocraticphilosopherThales(640-546 BC),dubbedthe "fatherof science",wasthe first
to postulate non-supernatural explanationsfornatural phenomena.Forexample,thatlandfloatson
waterand that earthquakesare causedbythe agitationof the wateruponwhichthe landfloats,rather
than the god Poseidon.[21] Thales'studentPythagorasof Samosfoundedthe Pythagoreanschool,which
investigatedmathematicsforitsownsake,andwasthe firstto postulate thatthe Earth isspherical in
shape.[22] Leucippus(5thcenturyBC) introducedatomism, the theorythatall matterismade of
indivisible,imperishableunitscalledatoms.Thiswasgreatlyexpandedonbyhispupil Democritusand
laterEpicurus.
Subsequently,PlatoandAristotle producedthe firstsystematicdiscussionsof natural philosophy,which
didmuch to shape laterinvestigationsof nature.Theirdevelopmentof deductive reasoningwasof
particularimportance andusefulnesstolaterscientificinquiry.Platofoundedthe PlatonicAcademyin
387 BC,whose mottowas "Letnone unversedingeometryenterhere", andturnedoutmanynotable
philosophers.Plato'sstudentAristotleintroducedempiricismandthe notionthatuniversal truthscanbe
arrivedat viaobservationandinduction,therebylayingthe foundationsof the scientificmethod.[23]
Aristotle alsoproducedmanybiological writingsthatwere empirical innature,focusingonbiological
causationand the diversityof life.He made countlessobservationsof nature,especiallythe habitsand
attributesof plantsandanimalsinthe worldaroundhim, classifiedmore than540 animal species,and
dissectedatleast50. Aristotle'swritingsprofoundlyinfluencedsubsequentIslamicandEuropean
scholarship,thoughtheywere eventuallysupersededinthe ScientificRevolution.
The importantlegacyof thisperiodincludedsubstantial advancesinfactual knowledge,especiallyin
anatomy,zoology,botany,mineralogy,geography,mathematicsandastronomy;anawarenessof the
importance of certainscientificproblems,especiallythose relatedtothe problemof change and its
causes;and a recognitionof the methodological importance of applyingmathematicstonatural
phenomenaandof undertakingempirical research.[24] Inthe Hellenisticage scholarsfrequently
employedthe principlesdevelopedinearlierGreekthought:the applicationof mathematicsand
deliberateempirical research,intheirscientificinvestigations.[25] Thus,clearunbrokenlinesof
influenceleadfromancientGreekandHellenisticphilosophers,tomedieval Muslimphilosophersand
scientists,tothe EuropeanRenaissanceandEnlightenment,tothe secularsciencesof the modernday.
Neitherreasonnorinquirybeganwiththe AncientGreeks,butthe Socraticmethoddid,alongwiththe
ideaof Forms,great advancesingeometry,logic,andthe natural sciences.AccordingtoBenjamin
Farrington,formerProfessorof ClassicsatSwanseaUniversity:
"Men were weighingforthousandsof yearsbefore Archimedesworkedoutthe lawsof equilibrium;they
musthave had practical and intuitional knowledgeof the principles involved.WhatArchimedesdidwas
to sort outthe theoretical implicationsof thispractical knowledge andpresentthe resultingbodyof
knowledge asalogicallycoherentsystem."

4. "With astonishmentwe findourselvesonthe thresholdof modernscience.Norshoulditbe supposed
that by some trickof translationthe extractshave beengivenanairof modernity.Farfromit.The
vocabularyof these writingsandtheirstyle are the source fromwhichourownvocabularyand style
have beenderived."[26]
The astronomerAristarchusof Samoswas the firstknownpersontopropose a heliocentricmodel of the
solarsystem,while the geographerEratosthenesaccuratelycalculatedthe circumference of the Earth.
Hipparchus(c.190 – c. 120 BC) producedthe firstsystematicstarcatalog.The level of achievementin
Hellenisticastronomyandengineeringisimpressivelyshownbythe Antikytheramechanism(150-100
BC),an analogcomputerfor calculatingthe positionof planets.Technological artifactsof similar
complexitydidnotreappearuntilthe 14thcentury,whenmechanical astronomical clocksappearedin
Europe.[27]
In medicine,Hippocrates(c.460 BC – c. 370 BC) and hisfollowerswere the firsttodescribe many
diseasesandmedical conditionsanddevelopedthe HippocraticOathforphysicians,still relevantandin
use today.Herophilos(335–280 BC) wasthe firstto base his conclusionsondissectionof the human
bodyand to describe the nervoussystem.Galen(129 – c. 200 AD) performedmanyaudacious
operations—includingbrainandeye surgeries—thatwere nottriedagainforalmosttwo millennia.
In HellenisticEgypt,the mathematicianEuclidlaiddownthe foundationsof mathematical rigorand
introducedthe conceptsof definition,axiom,theoremandproof still inuse todayinhisElements,
consideredthe mostinfluential textbookeverwritten.[29] Archimedes,consideredone of the greatest
mathematiciansof all time,[30] iscreditedwithusingthe methodof exhaustiontocalculate the area
underthe arc of a parabolawiththe summationof aninfinite series,andgave a remarkablyaccurate
approximationof Pi.[31] He isalsoknowninphysicsforlayingthe foundationsof hydrostatics,statics,
and the explanationof the principle of the lever.
Theophrastuswrote some of the earliestdescriptionsof plantsandanimals,establishingthe first
taxonomyandlookingatmineralsintermsof theirpropertiessuchashardness.Plinythe Elder
producedwhatisone of the largestencyclopediasof the natural worldin77 AD,and mustbe regarded
as the rightful successortoTheophrastus.Forexample,he accuratelydescribesthe octahedral shapeof
the diamond,andproceedstomentionthatdiamonddustisusedbyengraverstocut andpolishother
gemsowingtoits greathardness.Hisrecognitionof the importance of crystal shape isa precursorto
moderncrystallography,whilementionof numerousothermineralspresagesmineralogy.He also
recognisesthatothermineralshave characteristiccrystal shapes,butinone example,confusesthe
crystal habitwiththe work of lapidaries.He wasalsothe firstto recognise thatamberwasa fossilized
resinfrompine treesbecause he hadseensampleswithtrappedinsectswithinthem.
India
Mathematics:The earliesttracesof mathematical knowledge inthe Indiansubcontinentappearwiththe
IndusValleyCivilization(c.4thmillenniumBC~c. 3rd millenniumBC).The peopleof thiscivilization
made brickswhose dimensionswereinthe proportion4:2:1,consideredfavorableforthe stabilityof a
brickstructure.[32] Theyalsotriedto standardize measurementof lengthtoa highdegree of accuracy.

5. Theydesignedaruler—the Mohenjo-daroruler—whose unitof length(approximately1.32inchesor 3.4
centimetres)wasdividedintotenequal parts.BricksmanufacturedinancientMohenjo-darooftenhad
dimensionsthatwere integral multiplesof thisunitof length.[33]
IndianastronomerandmathematicianAryabhata(476-550),inhis Aryabhatiya(499) introduceda
numberof trigonometricfunctions(includingsine,versine,cosine andinversesine),trigonometric
tables,andtechniquesandalgorithmsof algebra.In628 AD,Brahmagupta suggestedthatgravitywasa
force of attraction.[34][35] He alsolucidlyexplainedthe use of zeroasboth a placeholderandadecimal
digit,alongwiththe Hindu-Arabicnumeral systemnow useduniversallythroughoutthe world.Arabic
translationsof the twoastronomers'textswere soonavailable inthe Islamicworld,introducingwhat
wouldbecome Arabicnumeralstothe IslamicWorldbythe 9th century.[36][37] Duringthe 14th–16th
centuries,the Keralaschool of astronomyandmathematicsmade significantadvancesinastronomyand
especiallymathematics,includingfieldssuchastrigonometryandanalysis.Inparticular,Madhavaof
Sangamagramais consideredthe "founderof mathematical analysis".[38]
Astronomy:The firsttextual mentionof astronomical conceptscomesfromthe Vedas,religious
literature of India.[39] AccordingtoSarma(2008): "One findsinthe Rigvedaintelligentspeculations
aboutthe genesisof the universe fromnonexistence,the configurationof the universe,the spherical
self-supportingearth,andthe yearof 360 daysdividedinto12 equal partsof 30 dayseach witha
periodical intercalarymonth.".[39] The first12 chaptersof the SiddhantaShiromani,writtenbyBhāskara
inthe 12th century,covertopicssuch as: meanlongitudesof the planets;true longitudesof the planets;
the three problemsof diurnal rotation;syzygies;lunareclipses;solareclipses;latitudesof the planets;
risingsandsettings;the moon'screscent;conjunctionsof the planetswitheachother;conjunctionsof
the planetswiththe fixedstars;andthe patasof the sun andmoon.The 13 chaptersof the secondpart
coverthe nature of the sphere,aswell assignificantastronomical andtrigonometriccalculationsbased
on it.
NilakanthaSomayaji'sastronomical treatise the Tantrasangrahasimilarinnature tothe Tychonicsystem
proposedbyTycho Brahe had beenthe mostaccurate astronomical model until the time of Johannes
Keplerinthe 17th century.[40]
Linguistics:Some of the earliestlinguisticactivitiescanbe foundinIronAge India(1st millenniumBC)
withthe analysisof Sanskritforthe purpose of the correct recitationandinterpretationof Vedictexts.
The most notable grammarianof SanskritwasPāṇini (c.520–460 BC),whose grammar formulatesclose
to 4,000 ruleswhichtogetherformacompact generative grammarof Sanskrit.Inherentinhisanalytic
approach are the conceptsof the phoneme,the morphemeandthe root.
Medicine:FindingsfromNeolithicgraveyardsinwhatisnow Pakistanshow evidence of proto-dentistry
amongan earlyfarmingculture.[41] Ayurvedaisasystemof traditional medicinethatoriginatedin
ancientIndiabefore 2500 BC,[42] and isnow practicedasa formof alternative medicine inotherparts
of the world.Itsmostfamoustextisthe Suśrutasamhitāof Suśruta,whichisnotable fordescribing
proceduresonvariousforms of surgery,includingrhinoplasty,the repairof tornearlobes,perineal
lithotomy,cataractsurgery,andseveral otherexcisionsandothersurgical procedures.

6. Metallurgy:The wootz,crucible andstainlesssteelswere discoveredinIndia,andwere widely exported
inClassicMediterraneanworld.ItwasknownfromPlinythe Elderasferrumindicum.IndianWootzsteel
was heldinhighregardinRoman Empire,wasoftenconsideredtobe the best.AfterinMiddle Age it
was importedinSyriatoproduce withspecial techniquesthe "Damascussteel"bythe year1000.[43]
The Hindusexcel inthe manufacture of iron,andin the preparationsof those ingredientsalongwith
whichitis fusedtoobtainthat kindof softironwhichis usuallystyledIndiansteel (Hindiah).Theyalso
have workshopswhereinare forgedthe mostfamoussabresinthe world.
China
Mathematics:Fromthe earliestthe Chinese usedapositional decimal systemoncountingboardsin
orderto calculate.To express10,a single rodisplacedinthe secondbox fromthe right.The spoken
language usesasimilarsystemtoEnglish:e.g.fourthousandtwohundredseven.Nosymbol wasused
for zero.By the 1st centuryBC, negative numbersanddecimalfractionswere inuse andThe Nine
Chaptersonthe Mathematical ArtincludedmethodsforextractinghigherorderrootsbyHorner's
methodandsolvinglinearequationsandbyPythagoras'theorem.Cubicequationswere solvedinthe
Tang dynastyand solutionsof equationsof orderhigherthan3 appearedinprintin1245 AD byCh'in
Chiu-shao.Pascal'striangle forbinomial coefficientswasdescribedaround1100 by JiaXian.
Althoughthe firstattemptsatan axiomatisationof geometryappearinthe Mohistcanonin330 BC,
developedalgebraicmethodsingeometryinthe 3rdcenturyAD and alsocalculatedpi to5 significant
figures.In480, Zu Chongzhi improvedthisbydiscoveringthe ratio355 113 whichremainedthe most
accurate value for1200 years.
Astronomy:Astronomical observationsfromChinaconstitute the longest continuoussequence fromany
civilisationandinclude recordsof sunspots(112recordsfrom364 BC),supernovas(1054), lunarand
solareclipses.Bythe 12th century,theycouldreasonablyaccuratelymake predictionsof eclipses,but
the knowledge of this waslostduringthe Mingdynasty,sothat the JesuitMatteoRicci gainedmuch
favourin1601 by hispredictions.[46] By635 Chinese astronomershadobservedthatthe tailsof comets
alwayspointawayfromthe sun.
fromantiquity,the Chineseusedanequatorial systemfordescribingthe skiesanda star map from940
was drawnusinga cylindrical (Mercator) projection.The use of anarmillarysphere isrecordedfromthe
4th centuryBC and a sphere permanentlymountedinequatorial axisfrom52 BC. In 125 AD Zhang Heng
usedwaterpowerto rotate the sphere inreal time.Thisincludedringsforthe meridianandecliptic.By
1270 theyhad incorporatedthe principlesof the Arabtorquetum.
Seismology:Tobetterprepare forcalamities,ZhangHenginventedaseismometerin132 CE which
providedinstantalerttoauthoritiesinthe capital Luoyangthatan earthquake hadoccurredin a location
indicatedbya specificcardinal orordinal direction.[47] Althoughnotremorscouldbe feltinthe capital
whenZhangtoldthe court that an earthquake hadjustoccurredin the northwest,amessage came soon
afterwardsthatan earthquake hadindeedstruck400 km (248 mi) to 500 km(310 mi) northwestof
Luoyang(inwhat isnowmodernGansu).[48] Zhangcalledhisdevice the 'instrumentformeasuringthe

7. seasonal windsandthe movementsof the Earth' (Houfengdidongyi 候风地动仪),so-namedbecause
he and othersthoughtthat earthquakeswere mostlikelycausedbythe enormouscompressionof
trappedair.[49] See Zhang'sseismometerfor furtherdetails.
There are manynotable contributorstothe fieldof Chinese science throughoutthe ages.One of the
bestexampleswouldbe ShenKuo(1031–1095), a polymathscientistandstatesmanwhowasthe firstto
describe the magnetic-needle compassusedfornavigation,discoveredthe conceptof true north,
improvedthe designof the astronomical gnomon,armillarysphere,sighttube,andclepsydra,and
describedthe use of drydockstorepairboats.Afterobservingthe natural processof the inundation of
siltandthe findof marine fossilsinthe TaihangMountains(hundredsof milesfromthe PacificOcean),
ShenKuodevisedatheoryof landformation,orgeomorphology.He alsoadoptedatheoryof gradual
climate change inregionsovertime,afterobservingpetrifiedbamboofoundundergroundatYan'an,
Shaanxi province.If notforShenKuo'swriting,[50] the architectural worksof YuHao wouldbe little
known,alongwiththe inventorof movable typeprinting,Bi Sheng(990-1051). Shen'scontemporarySu
Song(1020–1101) was alsoa brilliantpolymath,anastronomerwhocreatedacelestial atlasof star
maps,wrote a pharmaceutical treatise withrelatedsubjectsof botany,zoology,mineralogy,and
metallurgy,andhaderectedalarge astronomical clocktowerin Kaifengcityin1088. To operate the
crowningarmillarysphere,hisclocktowerfeaturedanescapementmechanismandthe world'soldest
knownuse of an endlesspower-transmittingchaindrive.
The JesuitChinamissionsof the 16thand 17th centuries"learnedtoappreciate the scientific
achievementsof thisancientculture andmade themknowninEurope.Throughtheircorrespondence
Europeanscientistsfirstlearnedaboutthe Chinese science andculture."[51] Westernacademicthought
on the historyof Chinese technologyandscience wasgalvanizedbythe workof JosephNeedhamand
the NeedhamResearchInstitute.Amongthe technological accomplishmentsof Chinawere,accordingto
the BritishscholarNeedham,earlyseismological detectors(ZhangHenginthe 2ndcentury),the water-
poweredcelestial globe (ZhangHeng),matches,the independentinventionof the decimal system, dry
docks,slidingcalipers,the double-actionpistonpump,castiron,the blastfurnace,the ironplough,the
multi-tube seeddrill,the wheelbarrow,the suspensionbridge,the winnowingmachine,the rotaryfan,
the parachute,natural gas as fuel,the raised-reliefmap,the propeller,the crossbow,andasolidfuel
rocket,the multistage rocket,the horse collar,alongwithcontributionsinlogic,astronomy,medicine,
and otherfields.
However,cultural factorspreventedtheseChinese achievementsfromdevelopingintowhatwe might
call "modernscience".AccordingtoNeedham,itmayhave beenthe religiousandphilosophical
frameworkof Chinese intellectualswhichmade themunabletoacceptthe ideasof lawsof nature:
It was not thatthere was noorder innature for the Chinese,butratherthatit wasnot an order
ordainedbya rational personal being,andhence there wasnoconvictionthatrational personalbeings
wouldbe able tospell outintheirlesserearthlylanguagesthe divine code of lawswhichhe haddecreed
aforetime.The Taoists,indeed,wouldhave scornedsuchanideaas beingtoonaïve for the subtletyand
complexityof the universe astheyintuitedit.[52]

8. Science inthe Middle Ages
Withthe divisionof the RomanEmpire,the WesternRomanEmpire lostcontactwithmuchof itspast. In
the Middle East,Greekphilosophywasable tofindsome supportunderthe newlycreatedArabEmpire.
Withthe spreadof Islaminthe 7th and 8th centuries,aperiodof Muslimscholarship,knownasthe
IslamicGoldenAge,lasteduntilthe 13thcentury.Thisscholarshipwasaidedbyseveral factors.The use
of a single language,Arabic,allowedcommunicationwithoutneedof atranslator.AccesstoGreektexts
fromthe Byzantine Empire,alongwithIndiansourcesof learning,providedMuslimscholarsa
knowledge base tobuildupon.
While the Byzantine Empire still heldlearningcenterssuchasConstantinople,WesternEurope's
knowledge wasconcentratedinmonasteriesuntil the developmentof medievaluniversitiesinthe 12th
and 13th centuries.The curriculumof monasticschoolsincludedthe studyof the few available ancient
textsandof newworksonpractical subjectslike medicine[53] andtimekeeping.[54]
Islamic world
Main articles:Science inthe medieval IslamicworldandTimelineof science andengineeringinthe
Islamicworld
See also:AlchemyandchemistryinmedievalIslam, Islamicastronomy,Islamicmathematics,Islamic
medicine,Islamicphysics,Islamicpsychological thought,andEarlyMuslimsociology
muslimscientistsplacedfargreateremphasisonexperimentthanhadthe Greeks.[55] Thisledtoan
earlyscientificmethodbeingdevelopedinthe Muslimworld,where significantprogressinmethodology
was made,beginningwiththe experimentsof Ibnal-Haytham(Alhazen) onopticsfromc. 1000, in his
Bookof Optics.[56] The mostimportantdevelopmentof the scientificmethodwasthe use of
experimentstodistinguishbetweencompetingscientifictheoriessetwithinagenerallyempirical
orientation,whichbeganamongMuslimscientists.Ibnal-Haythamisalsoregardedasthe fatherof
optics,especiallyforhisempirical proof of the intromissiontheoryof light.Some have alsodescribedIbn
al-Haythamasthe "firstscientist"forhisdevelopmentof the modernscientificmethod.[57]
In mathematics,the mathematicianMuhammadibnMusaal-Khwarizmigave hisname tothe conceptof
the algorithm,while the termalgebraisderivedfromal-jabr,the beginningof the title of one of his
publications.WhatisnowknownasArabicnumeralsoriginallycame fromIndia,butMuslim
mathematiciansdidmake several refinementstothe numbersystem, suchasthe introductionof
decimal pointnotation.MathematicianAl-Battani (850-929) contributedtoastronomyand
mathematics,whilescholarAl-Razicontributedtochemistryandmedicine.
In astronomy,Al-Battani improvedthe measurementsof Hipparchus,preservedinthe translationof
Ptolemy'sHè Megalè Syntaxis(The greattreatise) translatedasAlmagest.Al-Battanialsoimprovedthe
precisionof the measurementof the precessionof the Earth'saxis.The correctionsmade to the

9. geocentricmodel byal-Battani,Ibnal-Haytham,[58] Averroesandthe Maragha astronomerssuchas
Nasiral-Dinal-Tusi,Mo'ayyeduddinUrdi andIbnal-Shatirare similartoCopernicanheliocentric
model.[59][60] Heliocentrictheoriesmayhave alsobeendiscussedbyseveralotherMuslim
astronomerssuch as Ja'far ibnMuhammadAbu Ma'shar al-Balkhi,[61] Abu-RayhanBiruni,AbuSaidal-
Sijzi,[62] Qutbal-Dinal-Shirazi,andNajmal-Dīnal-Qazwīnīal-Kātibī.[63]
Muslimchemistsandalchemistsplayedanimportantrole inthe foundationof modernchemistry.
Scholarssuch as Will Durant[64] and FieldingH.Garrison[65] consideredMuslimchemiststobe the
foundersof chemistry.Inparticular,JābiribnHayyānis"consideredbymanytobe the fatherof
chemistry".[66][67] The worksof ArabicscientistsinfluencedRogerBacon(whointroducedthe
empirical methodtoEurope,stronglyinfluencedbyhisreadingof Persianwriters),[68] andlaterIsaac
Newton.[69]
IbnSina (Avicenna) isregardedasthe mostinfluential philosopherof Islam.[70] He pioneeredthe
science of experimental medicine[71] andwasthe firstphysiciantoconductclinical trials.[72] Histwo
mostnotable worksinmedicine are the Kitābal-shifāʾ ("Book of Healing") andThe Canonof Medicine,
bothof whichwere usedasstandardmedicinal textsinboththe MuslimworldandinEurope well into
the 17th century.Amongsthismanycontributionsare the discoveryof the contagiousnature of
infectiousdiseases,[71] andthe introductionof clinical pharmacology.[73]
Some of the otherfamousscientistsfromthe Islamicworldincludeal-Farabi(polymath),Abual-Qasim
al-Zahrawi (pioneerof surgery),[74] AbūRayhānal-Bīrūnī(pioneerof Indology,[75] geodesyand
anthropology),[76] Nasīral-Dīnal-Tūsī(polymath),andIbnKhaldun(forerunnerof social sciences[77]
such as demography,[78] cultural history,[79] historiography,[80] philosophyof historyand
sociology),[81] amongmanyothers.
Islamicscience beganitsdeclineinthe 12th or 13th century,before the Renaissance inEurope,anddue
inpart to the 11th–13th centuryMongol conquests,duringwhichlibraries,observatories,hospitalsand
universitieswere destroyed.[82] The endof the IslamicGoldenAge ismarkedbythe destructionof the
intellectual centerof Baghdad,the capital of the Abbasidcaliphate in1258.[82]
Europe
An intellectualrevitalizationof Europe startedwiththe birthof medievaluniversitiesinthe 12th
century.The contact withthe IslamicworldinSpainandSicily,andduringthe Reconquistaandthe
Crusades,allowedEuropeansaccesstoscientificGreekandArabictexts,includingthe worksof Aristotle,
Ptolemy,JābiribnHayyān,al-Khwarizmi,Alhazen,Avicenna,andAverroes.Europeanscholarshadaccess
to the translationprogramsof Raymondof Toledo,whosponsoredthe 12th centuryToledoSchool of
TranslatorsfromArabic to Latin.Later translatorslike Michael ScotuswouldlearnArabicinorderto
studythese textsdirectly.The Europeanuniversitiesaidedmateriallyinthe translationandpropagation
of these textsandstarteda newinfrastructure whichwasneededforscientificcommunities.Infact,
Europeanuniversityputmanyworksaboutthe natural worldandthe studyof nature at the centerof its
curriculum,[83] withthe resultthatthe "medievaluniversitylaidfargreateremphasisonscience than
doesitsmoderncounterpartanddescendent."[84]

10. As well asthis,Europeansbegantoventure furtherandfurthereast(mostnotably,perhaps,Marco
Polo) asa resultof the Pax Mongolica.Thisledto the increasedawarenessof IndianandevenChinese
culture andcivilizationwithinthe Europeantradition.Technologicaladvanceswere alsomade,suchas
the earlyflightof Eilmerof Malmesbury(whohadstudiedMathematicsin11th centuryEngland),[85]
and the metallurgical achievementsof the Cistercianblastfurnace atLaskill.[86][87]
At the beginningof the 13th century,there were reasonablyaccurate Latintranslationsof the main
worksof almostall the intellectuallycrucial ancientauthors,allowingasoundtransferof scientificideas
viaboth the universitiesandthe monasteries.Bythen,the natural philosophycontainedinthese texts
beganto be extendedbynotable scholasticssuch asRobert Grosseteste,RogerBacon,AlbertusMagnus
and DunsScotus.Precursorsof the modernscientificmethod,influencedbyearliercontributionsof the
Islamicworld,canbe seenalreadyinGrosseteste'semphasisonmathematicsasa wayto understand
nature,and inthe empirical approachadmiredbyBacon,particularlyinhisOpusMajus.Pierre Duhem's
provocative thesisof the CatholicChurch'sCondemnationof 1277 ledto the studyof medieval science
as a seriousdiscipline,"butnoone inthe fieldanylongerendorseshisview thatmodernscience started
in1277".[88] However,manyscholarsagree withDuhem'sview thatthe Middle Ageswereaperiodof
importantscientificdevelopments.[89][90][91][92]
The firsthalf of the 14th centurysawmuch importantscientificworkbeingdone,largelywithinthe
frameworkof scholasticcommentariesonAristotle'sscientificwritings.[93] Williamof Ockham
introducedthe principleof parsimony:natural philosophersshouldnotpostulate unnecessaryentities,
so that motionisnota distinctthingbutisonlythe movingobject[94] andan intermediary"sensible
species"isnotneededtotransmitanimage of an objectto the eye.[95] Scholarssuchas JeanBuridan
and Nicole Oresme startedtoreinterpretelementsof Aristotle'smechanics.Inparticular,Buridan
developedthe theorythatimpetuswasthe cause of the motionof projectiles,whichwasa firststep
towardsthe modernconceptof inertia.[96] The OxfordCalculatorsbegantomathematicallyanalyzethe
kinematics of motion,makingthisanalysiswithoutconsideringthe causesof motion.[97]
In 1348, the BlackDeath andotherdisasterssealedasuddenendtothe previousperiodof massive
philosophicandscientificdevelopment.Yet,the rediscoveryof ancienttextswasimprovedafterthe Fall
of Constantinople in1453, whenmanyByzantine scholarshadtoseekrefuge inthe West.Meanwhile,
the introductionof printingwastohave great effectonEuropeansociety.The facilitateddissemination
of the printedworddemocratizedlearningandallowedafasterpropagationof new ideas.New ideas
alsohelpedtoinfluence the developmentof Europeanscienceatthispoint:notleastthe introductionof
Algebra.These developmentspavedthe wayforthe ScientificRevolution,whichmayalsobe
understoodasa resumptionof the processof scientificinquiry,haltedatthe startof the BlackDeath.
Impact of science in Europe
See also:Continuitythesis,Declineof Westernalchemy,andNatural magic
Isaac Newtoninitiatedclassical mechanicsinphysics.
GalileoGalilei,fatherof modernscience.[98]

11. The renewal of learninginEurope,thatbeganwith12th centuryScholasticism, came toanendabout
the time of the BlackDeath,and the initial periodof the subsequentItalianRenaissanceissometimes
seenasa lull inscientificactivity.The NorthernRenaissance,onthe otherhand,showedadecisive shift
infocus fromAristoteleiannatural philosophytochemistryandthe biological sciences(botany,
anatomy,and medicine).[99] Thusmodernscience inEurope wasresumedinaperiodof greatupheaval:
the ProtestantReformationandCatholicCounter-Reformation;the discoveryof the Americasby
ChristopherColumbus;the Fall of Constantinople;butalsothe re-discoveryof Aristotle during the
Scholasticperiodpresagedlarge social andpolitical changes.Thus,asuitable environmentwascreated
inwhichit became possibletoquestionscientificdoctrine,inmuchthe same waythat Martin Luther
and JohnCalvinquestionedreligiousdoctrine. The worksof Ptolemy(astronomy) andGalen(medicine)
were foundnotalwaystomatch everydayobservations.WorkbyVesaliusonhumancadaversfound
problemswiththe Galenicviewof anatomy.[100]
The willingnesstoquestionpreviouslyheldtruthsandsearchfor new answersresultedinaperiodof
majorscientificadvancements,nowknownasthe ScientificRevolution.The ScientificRevolutionis
traditionallyheldbymosthistorianstohave begunin1543, whenthe booksDe humani corporisfabrica
(Onthe Workingsof the HumanBody) by AndreasVesalius,andalsoDe Revolutionibus,bythe
astronomerNicolausCopernicus,werefirstprinted.The thesisof Copernicus'bookwasthatthe Earth
movedaroundthe Sun.The periodculminatedwiththe publicationof the Philosophiæ Naturalis
PrincipiaMathematicain1687 by Isaac Newton,representativeof the unprecedentedgrowthof
scientificpublicationsthroughoutEurope.
Othersignificantscientificadvancesweremade duringthistime byGalileoGalilei,EdmondHalley,
RobertHooke,ChristiaanHuygens,TychoBrahe,JohannesKepler,GottfriedLeibniz,andBlaisePascal.In
philosophy,majorcontributionswere made byFrancisBacon,SirThomasBrowne,René Descartes,and
ThomasHobbes.The scientificmethodwasalsobetterdevelopedasthe modernwayof thinking
emphasizedexperimentationandreasonovertraditional considerations.
Age ofEnlightenment
The Age of EnlightenmentwasaEuropeanaffair.The 17th centurybroughtdecisive stepstowards
modernscience,whichacceleratedduringthe 18thcentury.Directlybasedonthe works[103] of
Newton,Descartes,Pascal andLeibniz,the waywasnow clearto the developmentof modern
mathematics,physicsandtechnologybythe generationof BenjaminFranklin(1706–1790), Leonhard
Euler(1707–1783), Mikhail Lomonosov(1711–1765) and Jeanle Rond d'Alembert(1717–1783). Denis
Diderot'sEncyclopédie,publishedbetween1751 and1772 brought thisnew understandingtoa wider
audience.The impactof thisprocesswasnot limitedtoscience andtechnology,butaffectedphilosophy
(Immanuel Kant,DavidHume),religion(the increasinglysignificantimpactof science uponreligion),and
societyandpoliticsingeneral (AdamSmith,Voltaire).The earlymodernperiodisseenasafloweringof
the EuropeanRenaissance,inwhatisoftenknownasthe ScientificRevolution,viewedasa foundation
of modernscience.[104]

12. Romanticism in science
The RomanticMovementof the early19th centuryreshapedscience byopeningupnew pursuits
unexpectedinthe classical approachesof the Enlightenment.Majorbreakthroughscame inbiology,
especiallyinDarwin'stheoryof evolution,aswellasphysics(electromagnetism),mathematics(non-
Euclideangeometry,grouptheory) andchemistry(organicchemistry).The decline of Romanticism
occurredbecause a newmovement,Positivism, begantotake holdof the idealsof the intellectualsafter
1840 and lasteduntil about1880.
Modern science
The scientificrevolutionestablishedscience asasource for the growthof knowledge.[clarification
needed][105] Duringthe 19th century,the practice of science became professionalizedand
institutionalizedinwaysthatcontinuedthroughthe 20th century.Asthe role of scientificknowledge
grewin society,itbecame incorporatedwithmanyaspectsof the functioningof nation-states.[citation
needed]
Natural sciences
The scientificrevolutionisaconvenientboundarybetweenancientthoughtandclassical physics.
NicolausCopernicusrevivedthe heliocentricmodel of the solarsystem describedbyAristarchusof
Samos.Thiswas followedbythe firstknownmodel of planetarymotiongivenbyJohannesKeplerinthe
early17th century,whichproposedthatthe planetsfollow elliptical orbits,withthe Sunatone focus of
the ellipse.Galileo("Fatherof ModernPhysics") alsomade use of experimentstovalidate physical
theories,akeyelementof the scientificmethod.WilliamGilbertdidsome of the earliestexperiments
withelectricityandmagnetism,establishingthatthe Earth itself ismagnetic.
In 1687, Isaac Newtonpublishedthe PrincipiaMathematica,detailingtwocomprehensiveandsuccessful
physical theories:Newton'slawsof motion,whichledtoclassical mechanics;andNewton'sLaw of
Gravitation,whichdescribesthe fundamental force of gravity.
Duringthe early19th century,the behaviorof electricityandmagnetismwasstudiedbyFaraday,Ohm,
and others.These studiesledtothe unificationof the twophenomenaintoasingle theoryof
electromagnetism,byJamesClerkMaxwell (knownasMaxwell'sequations).
The beginningof the 20th centurybroughtthe start of a revolutioninphysics.The long-heldtheoriesof
Newtonwere shownnottobe correct inall circumstances.Beginningin1900, Max Planck,Albert
Einstein,NielsBohrand othersdevelopedquantumtheoriestoexplainvariousanomalousexperimental
results,byintroducingdiscreteenergylevels.Notonlydidquantummechanicsshow thatthe lawsof
motiondidnotholdon small scales,butevenmore disturbingly,the theoryof general relativity,
proposedbyEinsteinin1915, showedthatthe fixedbackgroundof spacetime,onwhichboth
Newtonianmechanicsandspecial relativitydepended,couldnotexist.In1925, WernerHeisenbergand
ErwinSchrödingerformulatedquantummechanics,whichexplainedthe precedingquantumtheories.
The observationbyEdwinHubble in1929 that the speedatwhichgalaxiesrecede positivelycorrelates

13. withtheirdistance,ledtothe understandingthatthe universe isexpanding,andthe formulationof the
Big Bang theorybyGeorgesLemaître.
The atomic bombusheredin"BigScience"inphysics.
In 1938 OttoHahn and FritzStrassmanndiscoverednuclearfission withradiochemical methods,andin
1939 Lise MeitnerandOtto RobertFrischwrote the firsttheoretical interpretationof the fissionprocess,
whichwaslaterimprovedbyNielsBohrandJohnA. Wheeler.Furtherdevelopmentstookplace during
WorldWar II, whichledto the practical applicationof radarand the developmentanduse of the atomic
bomb.Thoughthe processhad begunwiththe inventionof the cyclotronbyErnestO. Lawrence inthe
1930s, physicsinthe postwarperiodenteredintoaphase of what historianshave called"BigScience",
requiringmassivemachines,budgets,andlaboratoriesinordertotesttheirtheoriesandmove intonew
frontiers.The primarypatronof physicsbecame state governments,whorecognizedthatthe supportof
"basic"researchcouldoftenleadtotechnologiesuseful tobothmilitaryandindustrialapplications.
Currently,general relativityandquantummechanicsare inconsistentwitheachother,andeffortsare
underwaytounifythe two.
Chemistry
Modernchemistryemergedfromthe sixteenththroughthe eighteenthcenturiesthroughthe material
practicesand theoriespromotedbyalchemy,medicine,manufacturingandmining.[106] A decisive
momentcame when'chemistry'wasdistinguishedfromalchemyby RobertBoyle inhisworkThe
Sceptical Chymist,in1661; althoughthe alchemical traditioncontinuedforsome time afterhiswork.
Otherimportantstepsincludedthe gravimetricexperimentalpracticesof medical chemistslike William
Cullen,JosephBlack, TorbernBergmanandPierre Macquerandthrough the workof Antoine Lavoisier
(Fatherof Modern Chemistry) onoxygenandthe law of conservationof mass,whichrefutedphlogiston
theory.The theorythat all matterismade of atoms,whichare the smallestconstituentsof matterthat
cannot be brokendownwithoutlosingthe basicchemical andphysicalpropertiesof thatmatter,was
providedbyJohnDaltonin1803, althoughthe questiontookahundredyearstosettle asproven.Dalton
alsoformulatedthe lawof massrelationships.In1869, Dmitri Mendeleevcomposedhisperiodictable of
elementsonthe basisof Dalton'sdiscoveries.
The synthesisof ureabyFriedrichWöhleropenedanew researchfield,organicchemistry,andbythe
endof the 19th century,scientistswere able tosynthesizehundredsof organiccompounds.The later
part of the 19th centurysawthe exploitationof the Earth'spetrochemicals,afterthe exhaustionof the
oil supplyfromwhaling.Bythe 20th century,systematicproductionof refined materialsprovideda
readysupplyof productswhichprovidednotonlyenergy,butalsosyntheticmaterialsforclothing,
medicine,andeverydaydisposable resources.Applicationof the techniquesof organicchemistryto
livingorganismsresultedinphysiological chemistry,the precursortobiochemistry.The 20thcentury
alsosaw the integrationof physicsandchemistry,withchemical propertiesexplainedasthe resultof
the electronicstructure of the atom.LinusPauling'sbookonThe Nature of the Chemical Bondusedthe
principlesof quantummechanicstodeduce bondanglesinever-more complicatedmolecules.Pauling's
workculminatedinthe physical modellingof DNA,the secretof life (inthe wordsof FrancisCrick,1953).

14. In the same year,the Miller–Ureyexperimentdemonstratedinasimulationof primordial processes,
that basicconstituentsof proteins,simpleaminoacids,couldthemselvesbe builtupfromsimpler
molecules.
Geology
Geologyexistedasa cloudof isolated,disconnectedideasaboutrocks, minerals,andlandformslong
before itbecame acoherentscience.Theophrastus'workonrocks,Peri lithōn,remainedauthoritative
for millennia:itsinterpretationof fossilswasnotoverturneduntil afterthe ScientificRevolution.
Chinese polymathShen Kua(1031–1095) firstformulatedhypothesesforthe processof landformation.
Basedon hisobservationof fossilsinageological stratuminamountainhundredsof milesfromthe
ocean,he deducedthatthe land wasformedbyerosionof the mountainsand bydepositionof silt.
Plate tectonics—seafloorspreadingandcontinental driftillustratedona relief globe
Geologydidnotundergosystematicrestructuringduringthe ScientificRevolution,butindividual
theoristsmade importantcontributions.RobertHooke,forexample,formulatedatheoryof
earthquakes,andNicholasStenodevelopedthe theoryof superpositionandarguedthatfossilswere the
remainsof once-livingcreatures.BeginningwithThomasBurnet'sSacredTheoryof the Earth in 1681,
natural philosophersbegantoexplore the ideathatthe Earth had changedovertime.Burnetandhis
contemporariesinterpretedEarth'spastintermsof eventsdescribedinthe Bible,buttheirworklaidthe
intellectual foundationsforsecularinterpretationsof Earthhistory.
Moderngeology,like modernchemistry,graduallyevolvedduringthe 18thand early19th centuries.
Benoîtde Mailletandthe Comte de Buffonsaw the Earth as mucholderthanthe 6,000 years envisioned
by biblical scholars.Jean-Étienne Guettard andNicolasDesmaresthikedcentral France andrecorded
theirobservationsonsome of the firstgeological maps.Aidedbychemical experimentation,naturalists
such as Scotland'sJohnWalker,[107] Sweden'sTorbernBergman,andGermany'sAbrahamWerner
createdcomprehensive classificationsystemsforrocksand minerals—acollectiveachievementthat
transformedgeologyintoacuttingedge fieldbythe endof the eighteenthcentury.These early
geologistsalsoproposedageneralizedinterpretationsof EarthhistorythatledJamesHutton,Georges
CuvierandAlexandre Brongniart,followinginthe stepsof Steno,toargue thatlayersof rock couldbe
datedby the fossilstheycontained:aprinciple firstappliedtothe geologyof the ParisBasin.The use of
index fossilsbecame apowerfultool formakinggeological maps,because itallowedgeologiststo
correlate the rocksin one localitywiththose of similarage inother,distantlocalities.Overthe firsthalf
of the 19th century,geologistssuchasCharlesLyell,AdamSedgwick,andRoderickMurchisonapplied
the newtechnique torocksthroughoutEurope andeasternNorthAmerica,settingthe stage formore
detailed,government-fundedmappingprojectsinlaterdecades.
Midwaythroughthe 19th century,the focusof geologyshiftedfromdescriptionandclassificationto
attemptsto understandhowthe surface of the Earth had changed.The firstcomprehensive theoriesof
mountainbuildingwere proposedduringthisperiod,aswere the firstmoderntheoriesof earthquakes
and volcanoes.LouisAgassizandothersestablishedthe realityof continent-coveringice ages,and
"fluvialists"like AndrewCrombie Ramsayarguedthatrivervalleyswere formed,overmillionsof years

15. by the riversthatflowthroughthem.Afterthe discoveryof radioactivity,radiometricdatingmethods
were developed,startinginthe 20th century.AlfredWegener'stheoryof "continental drift"waswidely
dismissedwhenhe proposeditinthe 1910s, but new data gatheredinthe 1950s and1960s ledto the
theoryof plate tectonics,whichprovidedaplausiblemechanismforit.Plate tectonicsalsoprovideda
unifiedexplanationfora wide range of seeminglyunrelatedgeological phenomena.Since 1970 it has
servedasthe unifyingprinciple ingeology.
Geologists'embrace of plate tectonicsbecamepartof a broadeningof the fieldfromastudyof rocks
intoa studyof the Earth as a planet.Otherelementsof thistransformationinclude:geophysical studies
of the interiorof the Earth,the groupingof geology withmeteorologyandoceanographyasone of the
"earthsciences",andcomparisonsof Earthand the solar system'sotherrockyplanets.
Astronomy
Aristarchusof Samospublishedworkonhow todetermine the sizesanddistancesof the Sunandthe
Moon, andEratosthenesusedthisworktofigure the size of the Earth. Hipparchuslaterdiscoveredthe
precessionof the Earth.
Advancesinastronomyandinoptical systemsinthe 19th centuryresultedinthe firstobservationof an
asteroid(1Ceres) in1801, andthe discoveryof Neptunein1846.
George Gamow,RalphAlpher,andRobertHermanhad calculatedthatthere shouldbe evidence fora
Big Bang inthe backgroundtemperature of the universe.[108] In1964, ArnoPenziasandRobert
Wilson[109] discovereda3 Kelvin backgroundhissintheirBellLabsradiotelescope(the HolmdelHorn
Antenna),whichwasevidence forthishypothesis,andformedthe basisforanumberof resultsthat
helpeddeterminethe age of the universe.
SupernovaSN1987A wasobservedbyastronomers onEarth bothvisually,andinatriumphfor neutrino
astronomy,bythe solar neutrinodetectorsatKamiokande.Butthe solarneutrinofluxwasafractionof
itstheoreticallyexpectedvalue.Thisdiscrepancyforcedachange insome valuesinthe standard model
for particle physics.
Biology,medicine andgenetics
Axisscale:millionsof years.
Orange labels:knownice ages.
Alsosee:HumantimelineandNature timeline
Main articles:Historyof biology,Historyof molecularbiology,Historyof medicine,and Historyof
evolutionarythought
Semi-conservative DNA replication In1847, HungarianphysicianIgnácFülöpSemmelweisdramatically
reducedthe occurrencyof puerperal feverbysimplyrequiringphysicianstowashtheirhandsbefore
attendingtowomeninchildbirth.Thisdiscoverypredatedthe germtheoryof disease.However,

16. Semmelweis'findingswerenotappreciatedbyhiscontemporariesandcame intouse onlywith
discoveriesbyBritishsurgeonJosephLister,whoin1865 provedthe principlesof antisepsis. Lister's
workwas basedonthe importantfindingsbyFrenchbiologistLouisPasteur.Pasteurwasable tolink
microorganismswithdisease,revolutionizingmedicine.He alsodevisedone of the mostimportant
methodsinpreventive medicine,whenin1880 he produceda vaccine againstrabies.Pasteurinvented
the processof pasteurization,tohelppreventthe spreadof disease throughmilkandotherfoods.[110]
Perhapsthe mostprominent,controversial andfar-reachingtheoryinall of science hasbeenthe theory
of evolutionbynatural selectionputforwardbythe BritishnaturalistCharlesDarwininhisbookOnthe
Originof Speciesin1859. Darwinproposedthatthe featuresof all livingthings,includinghumans,were
shapedbynatural processesoverlongperiodsof time.The theoryof evolutioninitscurrentform
affectsalmostall areasof biology.[111] Implicationsof evolutiononfieldsoutsideof pure science have
ledto bothoppositionandsupportfromdifferentpartsof society,andprofoundlyinfluencedthe
popularunderstandingof "man'splace inthe universe".Inthe early20th century,the studyof heredity
became a majorinvestigationafterthe rediscoveryin1900 of the lawsof inheritance developedbythe
Moravian[112] monkGregor Mendel in1866. Mendel'slawsprovidedthe beginningsof the studyof
genetics,whichbecame amajorfieldof researchforbothscientificandindustrial research.By1953,
JamesD. Watson,FrancisCrick andMaurice Wilkinsclarifiedthe basicstructure of DNA,the genetic
material forexpressinglifeinall itsforms.[113] Inthe late 20th century,the possibilitiesof genetic
engineeringbecame practical forthe firsttime,andamassive international effortbeganin1990 to map
out an entire humangenome (the HumanGenome Project).
Ecology
Earthrise overthe Moon, Apollo8,NASA.Thisimage helpedcreate awarenessof the finitenessof Earth,
and the limitsof itsnatural resources.
The discipline of ecologytypicallytracesitsorigintothe synthesisof Darwinianevolutionand
Humboldtianbiogeography,inthe late 19th andearly20th centuries.Equallyimportantinthe rise of
ecology,however,were microbiologyandsoil science—particularlythe cycle of life concept,prominent
inthe workLouisPasteurandFerdinandCohn.The wordecologywascoinedbyErnst Haeckel,whose
particularlyholisticview of nature ingeneral (andDarwin'stheoryinparticular) wasimportantinthe
spreadof ecological thinking.Inthe 1930s, ArthurTansleyandothersbegandevelopingthe fieldof
ecosystemecology,whichcombinedexperimental soil science withphysiological conceptsof energyand
the techniquesof fieldbiology.The historyof ecologyinthe 20thcenturyiscloselytiedtothat of
environmentalism;the Gaiahypothesis,first formulatedinthe 1960s, and spreadinginthe 1970s, and
more recentlythe scientific-religiousmovementof DeepEcologyhave broughtthe twoclosertogether.
Social sciences
Successful use of the scientificmethodinthe physicalsciencesledtothe same methodologybeing
adaptedto betterunderstandthe manyfieldsof humanendeavor.Fromthiseffortthe social sciences
have beendeveloped.

17. Political science
ial sciences[citationneeded].However,the disciplinehasa clearsetof antecedentssuchasmoral
philosophy,political philosophy,political economy,history,andotherfieldsconcernedwithnormative
determinationsof whatoughttobe andwithdeducingthe characteristicsandfunctionsof the ideal
formof government.The rootsof politicsare in prehistory.Ineachhistoricperiodandinalmostevery
geographicarea,we can findsomeone studyingpoliticsandincreasingpolitical understanding.
In Westernculture,the studyof politicsisfirstfoundinAncientGreece.The antecedentsof European
politicstrace theirrootsback evenearlierthanPlatoandAristotle,particularlyinthe worksof Homer,
Hesiod,Thucydides,Xenophon,andEuripides.Later,Platoanalyzedpolitical systems,abstractedtheir
analysisfrommore literary- andhistory- orientedstudiesandappliedanapproachwe wouldunderstand
as closerto philosophy.Similarly,AristotlebuiltuponPlato'sanalysistoincludehistorical empirical
evidence inhisanalysis.
An ancientIndiantreatise onstatecraft,economicpolicyandmilitarystrategybyKautilya[114] and
Viṣhṇugupta,[115] whoare traditionallyidentifiedwithChāṇakya(c.350–-283 BCE).In thistreatise,the
behaviorsandrelationshipsof the people,the King,the State,the GovernmentSuperintendents,
Courtiers,Enemies,Invaders,andCorporationsare analysedanddocumented.RogerBoesche describes
the Arthaśāstraas "a bookof political realism,abookanalysinghow the political worlddoesworkand
not veryoftenstatinghowitoughtto work,a bookthat frequentlydisclosestoa kingwhatcalculating
and sometimesbrutal measureshe mustcarryout to preserve the state andthe commongood."[116]
Duringthe rule of Rome,famoushistorianssuchasPolybius,LivyandPlutarchdocumentedthe rise of
the Roman Republic,andthe organizationandhistoriesof othernations,whilestatesmenlike Julius
Caesar,Ciceroand othersprovideduswithexamplesof the politicsof the republicandRome'sempire
and wars.The studyof politicsduringthisage wasorientedtowardunderstandinghistory,
understandingmethodsof governing,anddescribingthe operationof governments.
Withthe fall of the WesternRomanEmpire,there arose amore diffuse arenaforpolitical studies.The
rise of monotheismand,particularlyforthe Westerntradition,Christianity,broughttolighta new space
for politicsandpolitical action[citationneeded].Duringthe Middle Ages,the studyof politicswas
widespreadinthe churchesandcourts.Workssuch as Augustine of Hippo'sThe Cityof God synthesized
currentphilosophiesandpolitical traditionswiththoseof Christianity,redefiningthe bordersbetween
whatwas religiousandwhatwaspolitical.Mostof the political questionssurroundingthe relationship
betweenChurchandState were clarifiedandcontestedinthisperiod.
inthe Middle Eastand laterotherIslamicareas,workssuchas the Rubaiyatof Omar KhayyamandEpic
of KingsbyFerdowsi providedevidence of political analysis,while the IslamicAristotelianssuchas
AvicennaandlaterMaimonidesand Averroes,continuedAristotle'straditionof analysisandempiricism,
writingcommentariesonAristotle'sworks.
Duringthe ItalianRenaissance,NiccolòMachiavelli establishedthe emphasisof modernpolitical science
on directempirical observationof politicalinstitutionsandactors.Later,the expansionof the scientific

18. paradigmduringthe Enlightenmentfurtherpushedthe studyof politicsbeyondnormative
determinations[citationneeded].Inparticular,the studyof statistics,tostudythe subjectsof the state,
has beenappliedtopollingandvoting.
In the 20th century,the studyof ideology,behaviouralismandinternational relationsledtoa multitude
of 'pol-sci'subdisciplinesincludingrational choice theory,votingtheory,game theory(alsousedin
economics),psephology,political geography/geopolitics,political psychology/political sociology,political
economy,policyanalysis,publicadministration,comparative political analysisandpeace studies/conflict
analysis.
Linguistics
Historical linguisticsemergedasanindependentfieldof studyatthe endof the 18th century.SirWilliam
JonesproposedthatSanskrit,Persian,Greek,Latin,Gothic,andCelticlanguagesall sharedacommon
base.AfterJones,anefforttocatalogall languagesof the worldwasmade throughoutthe 19th century
and intothe 20th century.Publicationof Ferdinandde Saussure'sCoursde linguistique générale created
the developmentof descriptivelinguistics.Descriptive linguistics,andthe relatedstructuralism
movementcausedlinguisticstofocusonhow language changesovertime,insteadof justdescribingthe
differencesbetweenlanguages.NoamChomskyfurtherdiversifiedlinguisticswiththe developmentof
generative linguisticsinthe 1950s. Hiseffortisbasedupona mathematical model of language that
allowsforthe descriptionandpredictionof validsyntax.Additionalspecialtiessuchassociolinguistics,
cognitive linguistics,andcomputational linguisticshave emergedfromcollaborationbetweenlinguistics
and otherdisciplines.
Economics
The supplyanddemandmodel
AdamSmithwrote The Wealthof Nations,the firstmodernworkof economics
The basisfor classical economicsformsAdamSmith'sAnInquiryintothe Nature andCausesof the
Wealthof Nations,publishedin1776. Smithcriticizedmercantilism, advocatingasystemof free trade
withdivisionof labour.He postulatedan"invisible hand"thatregulatedeconomicsystemsmade upof
actors guidedonlybyself-interest.Karl Marx developedanalternativeeconomictheory,calledMarxian
economics.Marxianeconomicsisbasedonthe labortheoryof value andassumesthe value of goodto
be basedon the amountof laborrequiredtoproduce it.Underthisassumption,capitalismwasbased
on employersnotpayingthe full value of workerslabortocreate profit.The Austrianschool responded
to Marxianeconomicsbyviewingentrepreneurshipasdrivingforce of economicdevelopment.This
replacedthe labortheoryof value bya systemof supplyanddemand.
In the 1920s, John Maynard Keynespromptedadivisionbetweenmicroeconomicsand
macroeconomics.UnderKeynesianeconomicsmacroeconomictrendscanoverwhelmeconomicchoices
made by individuals.Governmentsshouldpromote aggregate demandforgoodsasa meansto
encourage economicexpansion.FollowingWorldWarII,MiltonFriedmancreatedthe conceptof

19. monetarism.Monetarismfocusesonusingthe supplyanddemandof moneyasa methodforcontrolling
economicactivity.Inthe 1970s, monetarismhasadaptedintosupply-side economicswhichadvocates
reducingtaxesasa meansto increase the amountof moneyavailable foreconomicexpansion.
Othermodernschoolsof economicthoughtare New Classical economicsandNew Keynesian
economics.NewClassical economicswasdeveloped inthe 1970s, emphasizingsolidmicroeconomicsas
the basisfor macroeconomicgrowth.New Keynesianeconomicswascreatedpartiallyinresponse to
NewClassical economics,anddealswithhow inefficienciesinthe marketcreate aneedforcontrol by a
central bankor government.
The above "historyof economics"reflectsmoderneconomictextbooksandthismeansthatthe last
stage of a science isrepresentedasthe culminationof itshistory(Kuhn,1962).The "invisible hand"
mentionedinalostpage inthe middle of achapterin the middle of the "Wealthof Nations",1776,
advancesas Smith'scentral message.[clarificationneeded]Itisplayeddownthatthis"invisible hand"
acts only"frequently"andthatit is"no part of his[the individual's] intentions" because competition
leadstolowerpricesbyimitating"his"invention.Thatthis"invisible hand"prefers"the supportof
domestictoforeignindustry"iscleansed—oftenwithoutindicationthatpartof the citationis
truncated.[117] The openingpassage of the "Wealth"containingSmith'smessage isnevermentionedas
it cannotbe integratedintomoderntheory:"Wealth"dependsonthe divisionof labourwhichchanges
withmarketvolume andonthe proportionof productive toUnproductive labor.
Psychology
The end of the 19th centurymarks the start of psychologyasa scientificenterprise.The year1879 is
commonlyseenasthe start of psychologyasan independentfieldof study.InthatyearWilhelmWundt
foundedthe firstlaboratorydedicatedexclusivelytopsychologicalresearch(inLeipzig).Otherimportant
earlycontributorstothe fieldinclude HermannEbbinghaus(apioneerinmemorystudies),IvanPavlov
(whodiscoveredclassical conditioning),WilliamJames,andSigmundFreud.Freud'sinfluence hasbeen
enormous,thoughmore ascultural iconthan a force in scientificpsychology.
The 20th centurysaw a rejectionof Freud'stheoriesasbeingtoounscientific,anda reactionagainst
Edward Titchener'satomisticapproachof the mind.Thisledto the formulationof behaviorismbyJohn
B. Watson,whichwas popularizedbyB.F.Skinner.Behaviorismproposedepistemologicallylimiting
psychological studytoovertbehavior,since thatcouldbe reliablymeasured.Scientificknowledge of the
"mind"wasconsidered toometaphysical,henceimpossibletoachieve.
The final decadesof the 20th centuryhave seenthe rise of a new interdisciplinaryapproachtostudying
humanpsychology,knowncollectivelyascognitivescience.Cognitivescience againconsidersthe mind
as a subjectforinvestigation,usingthe toolsof psychology,linguistics,computerscience,philosophy,
and neurobiology.Newmethodsof visualizingthe activityof the brain,suchasPET scansand CAT scans,
beganto exerttheirinfluenceaswell,leading some researcherstoinvestigate the mindbyinvestigating
the brain,rather thancognition.These new formsof investigationassume thatawide understandingof
the humanmindis possible,andthatsuch an understandingmaybe appliedtootherresearchdomains,
such as artificial intelligence.

20. Sociology
IbnKhalduncan be regardedas the earliestscientificsystematicsociologist.[118] The modernsociology,
emergedinthe early19th centuryas the academicresponse tothe modernizationof the world.Among
manyearlysociologists(e.g.,ÉmileDurkheim),the aimof sociologywasinstructuralism, understanding
the cohesionof social groups,anddevelopingan"antidote"tosocial disintegration.Max Weberwas
concernedwiththe modernizationof societythrough the conceptof rationalization,whichhe believed
wouldtrapindividualsinan"ironcage" of rational thought.Some sociologists,includingGeorgSimmel
and W. E. B. Du Bois,utilizedmore microsociological,qualitativeanalyses.Thismicrolevel approach
playedanimportantrole inAmericansociology,withthe theoriesof George HerbertMeadandhis
studentHerbertBlumerresultinginthe creationof the symbolicinteractionismapproachtosociology.
Americansociologyinthe 1940s and 1950s was dominated largelybyTalcottParsons,whoarguedthat
aspectsof societythat promotedstructural integrationwere therefore "functional".Thisstructural
functionalismapproachwasquestionedinthe 1960s, whensociologistscame tosee thisapproachas
merelyajustificationforinequalitiespresentinthe statusquo.Inreaction,conflicttheorywas
developed,whichwasbasedinparton the philosophiesof Karl Marx.Conflicttheoristssaw societyas
an arena inwhichdifferentgroupscompete forcontrol overresources.Symbolicinteractionismalso
came to be regardedascentral to sociological thinking.ErvingGoffmansaw social interactionsasastage
performance,withindividualspreparing"backstage"andattemptingtocontrol theiraudience through
impressionmanagement.Whilethese theoriesare currentlyprominentinsociological thought,other
approachesexist,includingfeministtheory,post-structuralism, rational choice theory,and
postmodernism.
Anthropology
Anthropologycanbestbe understoodasan outgrowthof the Age of Enlightenment.Itwasduringthis
periodthatEuropeansattemptedsystematicallytostudyhumanbehaviour.Traditionsof jurisprudence,
history,philologyandsociologydevelopedduringthistime andinformedthe developmentof the social
sciencesof whichanthropologywasapart.
At the same time,the romanticreactiontothe EnlightenmentproducedthinkerssuchasJohann
GottfriedHerderandlaterWilhelmDiltheywhose workformedthe basisforthe culture conceptwhich
iscentral to the discipline.Traditionally,muchof the historyof the subjectwasbasedoncolonial
encountersbetweenWesternEurope andthe restof the world,and muchof 18th- and 19th-century
anthropologyisnowclassedasformsof scientificracism.
Duringthe late 19th-century,battlesoverthe "studyof man" tookplace betweenthose of an
"anthropological"persuasion(relyingonanthropometrical techniques) andthose of an"ethnological"
persuasion(lookingatculturesandtraditions),andthese distinctionsbecame partof the laterdivide
betweenphysical anthropologyandcultural anthropology,the latterusheredinbythe studentsof Franz
Boas.

21. In the mid-20thcentury,muchof the methodologiesof earlieranthropological andethnographical study
were reevaluated withaneye towardsresearchethics,whileatthe same time the scope of investigation
has broadenedfarbeyondthe traditionalstudyof "primitive cultures"(scientificpractice itself isoften
an arena of anthropological study).
The emergence of paleoanthropology,ascientificdiscipline whichdrawsonthe methodologiesof
paleontology,physical anthropologyandethology,amongotherdisciplines,andincreasinginscope and
momentumfromthe mid-20thcentury,continuestoyieldfurtherinsightsintohuman origins,evolution,
geneticandcultural heritage,andperspectivesonthe contemporaryhumanpredicamentaswell.
Emergingdisciplines
Duringthe 20th century,a numberof interdisciplinaryscientificfieldshave emerged.Examplesinclude:
Communication studiescombinesanimalcommunication,informationtheory,marketing,public
relations,telecommunicationsandotherformsof communication.
Computerscience,builtuponafoundationof theoretical linguistics,discrete mathematics,andelectrical
engineering,studiesthe nature andlimitsof computation.Subfieldsinclude computability,
computational complexity,database design,computernetworking,artificialintelligence,andthe design
of computerhardware.One areainwhichadvancesincomputinghave contributedtomore general
scientificdevelopmentisbyfacilitatinglarge-scale archivingof scientificdata.Contemporarycomputer
science typicallydistinguishesitself byemphasisingmathematical 'theory'incontrastto the practical
emphasisof software engineering.
Environmental science isaninterdisciplinaryfield.Itdrawsuponthe disciplinesof biology,chemistry,
earthsciences,ecology,geography,mathematics,andphysics.
Materialsscience hasitsroots inmetallurgy,mineralogy,andcrystallography.Itcombineschemistry,
physics,andseveral engineeringdisciplines.The fieldstudiesmetals,ceramics,glass,plastics,
semiconductors,andcompositematerials.
Academic study
As an academicfield,historyof science andtechnologybeganwiththe publicationof WilliamWhewell's
Historyof the Inductive Sciences(firstpublishedin1837). A more formal studyof the historyof science
as an independentdiscipline waslaunchedbyGeorge Sarton'spublications,Introductiontothe History
of Science (1927) andthe Isisjournal (foundedin1912). Sartonexemplifiedthe early20th-centuryview
of the historyof science asthe historyof great menand greatideas.He sharedwithmanyof his
contemporariesaWhiggishbelief inhistoryasa recordof the advancesanddelaysinthe march of
progress.The historyof science wasnota recognizedsubfieldof Americanhistoryinthisperiod,and
mostof the work wascarriedout by interestedscientistsandphysiciansratherthanprofessional
historians.[119] With the workof I. BernardCohenat Harvard, the historyof science became an
establishedsubdiscipline of historyafter1945.[120]

22. The historyof mathematics,historyof technology,andhistoryof philosophyare distinctareasof
researchand are coveredin otherarticles.Mathematicsiscloselyrelatedtobutdistinctfromnatural
science (atleastinthe modernconception).Technologyislikewise closelyrelatedtobutclearlydiffers
fromthe searchfor empirical truth.
Historyof science isanacademicdiscipline,withaninternationalcommunityof specialists.Main
professionalorganizationsforthisfieldinclude the Historyof Science Society,the BritishSocietyforthe
Historyof Science,andthe EuropeanSocietyforthe Historyof Science.
Much of the studyof the historyof science hasbeendevotedtoansweringquestionsaboutwhat
science is,howitfunctions,andwhetheritexhibitslarge-scale patternsandtrends.[121] The sociology
of science inparticularhasfocusedonthe waysin whichscientistswork,lookingcloselyatthe waysin
whichthey"produce"and"construct"scientificknowledge.Since the 1960s, a commontrendin science
studies(the studyof the sociologyandhistoryof science)hasbeentoemphasize the "human
component"of scientificknowledge,andtode-emphasize the view thatscientificdataare self-evident,
value-free,andcontext-free.[122] The fieldof Science andTechnologyStudies,anareathat overlaps
and ofteninformshistorical studiesof science,focusesonthe social contextof science inboth
contemporaryandhistorical periods.
Humboldtianscience referstothe early19th centuryapproachof combiningscientificfieldworkwith
the age of Romanticismsensitivity,ethicsandaestheticideals.[123] Ithelpedtoinstall natural historyas
a separate field,gave base forecologyandwasbasedonthe role model of scientist,naturalistand
explorerAlexandervonHumboldt.[124] The later19th centurypositivismassertedthatall authentic
knowledge allowsverificationand thatall authenticknowledge assumesthatthe onlyvalidknowledgeis
scientific.[125]
A majorsubjectof concernand controversyinthe philosophyof sciencehasbeenthe nature of theory
change in science.Karl Popperarguedthatscientificknowledge is progressiveandcumulative;Thomas
Kuhn,that scientificknowledge movesthrough"paradigmshifts"andisnotnecessarilyprogressive;and
Paul Feyerabend,thatscientificknowledge isnotcumulativeorprogressiveandthatthere can be no
demarcationin termsof methodbetweenscience andanyotherformof investigation.[126]
The mid 20th centurysaw a seriesof studiesrelyingtothe role of science ina social context,starting
fromThomas Kuhn'sThe Structure of ScientificRevolutionsin1962. Itopenedthe studyof science to
newdisciplinesbysuggestingthatthe evolutionof science wasinpartsociologicallydeterminedand
that positivismdidnotexplainthe actual interactionsandstrategiesof the humanparticipantsin
science.AsThomasKuhnput it,the historyof science maybe seeninmore nuancedterms,suchas that
of competingparadigmsorconceptual systemsinawidermatrix thatincludesintellectual,cultural,
economicandpolitical themesoutsideof science."Partlybyselectionandpartlybydistortion,the
scientistsof earlieragesare implicitlypresentedashavingworkeduponthe same setof fixedproblems
and inaccordance withthe same setof fixedcanonsthatthe mostrecentrevolutioninscientifictheory
and methodmade seemscientific."[127]

23. Furtherstudies,e.g.JeromeRavetz1971 ScientificKnowledge anditsSocial Problemsreferredtothe
role of the scientificcommunity,asa social construct,inacceptingor rejecting(objective)scientific
knowledge.[128] The Science warsof the 1990 were aboutthe influenceof especiallyFrench
philosophers,whichdeniedthe objectivityof science ingeneral orseemedtodoso.Theydescribedas
well differencesbetweenthe idealizedmodel of apure science andthe actual scientificpractice;while
scientism,arevival of the positivismapproach,saw inprecise measurementandrigorouscalculationthe
basisfor finallysettlingenduringmetaphysical andmoral controversies.[129][130] However,more
recentlysome of the leadingcritical theoristshave recognizedthattheirpostmoderndeconstructions
have at timesbeencounter-productive,andare providingintellectualammunitionforreactionary
interests.BrunoLatournotedthat"dangerousextremistsare usingthe verysame argumentof social
constructiontodestroyhard-wonevidence thatcouldsave ourlives.WasIwrong to participate inthe
inventionof thisfieldknownasscience studies?Isitenoughtosay that we didnot reallymeanwhatwe
meant?"[131]
The Plight of Many Scientific Innovators.
One recurringobservationinthe historyof science involvesthe struggleforrecognitionof first-rate
scientistsworkingonthe peripheryof the scientificestablishment.Forinstance,the greatphysicistLord
Rayleighlookedback(citedhere) on JohnJamesWaterston'sseminal paperonthe kinetictheoryof
gases.The historyof the neglectof Waterston'spath-breakingarticle,Rayleighfelt,suggeststhat"a
youngauthor whobelieveshimself capable of greatthingswouldusuallydowell tosecure favourable
recognitionof the scientificworld... before embarkinguponhigherflights."
WilliamHarvey'sexperiencesledhimtoanevenmore pessimisticview:[132]
"But whatremainsto be saidaboutthe quantityandsource of the bloodwhichthuspasses,isof so
novel andunheard-of characterthatI not onlyfearinjurytomyself fromthe envyof a few,butI tremble
lestI have mankindatlarge for my enemies,somuchdothwontand custom, that become asanother
nature,and doctrine once sownandthat hathstruck deeproot,and respectforantiquity,influence all
men."
In more general terms,ThomasK.Merton[133] remarksthat "the historyof science aboundsin
instances[134] of basicpapershavingbeenwrittenbycomparativelyunknownscientists,only tobe
rejectedorneglectedforyears."