CopernicusPolishname:MikolajKopernik.Polishastronomerandmathematicianwho,asastudent,studiedcanonlaw,mathematics,andmedicineatCracow,Bologna,Rome,Padua,andFerrara.Copernicusbecameinterestedinastronomyandpublishedanearlydescriptionofhis"heliocentric"modelofthesolarsysteminCommentariolus(1512).Inthismodel,thesunwasactuallynotexactlythecenterofthesolarsystem,butwasslightlyoffsetfromthecenterusingadeviceinventedbyPtolemyknownastheequantpoint.TheideathattheSunwasthecenterofthesolarsystemwasnotnew(similartheorieshadbeenproposedbyAristarchusandNicholasofCusa),butCopernicusalsoworkedouthissysteminfullmathematicaldetail.EventhoughthemathematicsinhisdescriptionwasnotanysimplerthanPtolemy's,itrequiredfewerbasicassumptions.BypostulatingonlytherotationoftheEarth,revolutionaboutthesun,andtiltofEarth'srotationalaxis,Copernicuscouldexplaintheobservedmotionoftheheavens.However,becauseCopernicusretainedcircularorbits,hissystemrequiredtheinclusionofepicycles.Unfortunately,outoffearthathisideasmightgethimintotroublewiththechurch,Copernicusdelayedpublicationofthem.In1539,CopernicustookonRheticusasastudentandhandedoverhismanuscripttohimtowriteapopularizationoftheheliocentrictheory,publishedasNarratioPrimain1540.Shortlybeforehisdeath,RheticusconvincedCopernicustoallowpublicationofhisoriginalmanuscript,andDeRevolutionibusOrbiumCoelestiumwaspublishedin1543.Copernicusproposedhistheoryasatruedescription,notjustatheorytosaveappearances.UnlikeBuridanandOresme,hedidnotthinkthatanytheorywhichsavedappearanceswasvalid,insteadbelievingthattherecouldonlybeasingletruetheory.Whentheworkwaspublished,however,AndreasOsianderaddedanunauthorized用心爱心专心prefacestatingthatthecontentswasmerelyadevicetosimplifycalculations.Copernicusadaptedphysicstothedemandsofastronomy,believingthattheprinciplesofPtolemy'ssystemwereincorrect,notthemathorobservations.Hewasthefirstpersoninhistorytocreateacompleteandgeneralsystem,combiningmathematics,physics,andcosmology.(Ptolemy,forinstance,hadtreatedeachplanetseparately.)Copernicus'ssystemwastaughtinsomeuniversitiesinthe1500sbuthadnotpermeatedtheacademicworlduntilapproximately1600.Somepeople,amongwhomJohnDonneandWilliamShakespearewerethemostinfluential,fearedCopernicus'stheory,feelingthatitdestroyedhierarchalnaturalorderwhichwouldinturndestroysocialorderandbringaboutchaos.Indeed,somepeople(suchasBruno),usedCopernicus'stheorytojustifyradicaltheologicalviews.BeforeCopernicusformulatedhistheoryofthesolarsystem,astronomyinEuropehadstagnated.AftertheAlmagesthadbeentranslatedintoLatin,EuropeanastronomerssuchastheAustrianmathematicianGeorgvonPeurbachandtheGermanastronomerRegiomontanusproposednonewtheories,attemptinginsteadtorefinetheflawedsystemalreadylaidoutbyPtolemy.TheastronomytextbookusedforteachingwasstillTheSphere,thesamebookthathadbeeninusesincethe1200s.Ratherthanformulatingnewtheories,astronomershadbusiedthemselvesin"savingappearances,"whichconsistedoftryingtopatchitupPtolemy'scumbersomeandinaccuratemodel.Copernicus,however,wipedtheslatecleaninasinglebroadstroke,andproposedafundamentallydifferentmodelinwhichtheplanetsallcircledtheSuninDeRevolutionibusOrbiumCoelestium.WhileradicallydifferentfromPtolemy'smodel,Copernicus'sheliocentrictheorywashardlyanoriginalidea.SimilartheorieshadbeenproposedbyAristarchusasearlyasthethirdcenturyB.C.,andNicholasdeCusa,aGermanscholar,hadindependen...
