a history of science-2-第12章

按键盘上方向键 ← 或 → 可快速上下翻页，按键盘上的 Enter 键可回到本书目录页，按键盘上方向键 ↑ 可回到本页顶部！
————未阅读完？加入书签已便下次继续阅读！


stion　of　the　earth's　position　in　the　universe。　Therefore　the　voyage　of　Magellan　served　to　fortify；　rather　than　to　dispute；　the　Ptolemaic　theory。　According　to　that　theory；　as　we　have　seen；　the　earth　was　supposed　to　lie　immovable　at　the　centre　of　the　universe；　the　various　heavenly　bodies；　including　the　sun；　revolving　about　it　in　eccentric　circles。　We　have　seen　that　several　of　the　ancient　Greeks；　notably　Aristarchus；　disputed　this　conception；　declaring　for　the　central　position　of　the　sun　in　the　universe；　and　the　motion　of　the　earth　and　other　planets　about　that　body。　But　this　revolutionary　theory　seemed　so　opposed　to　the　ordinary　observation　that；　having　been　discountenanced　by　Hipparchus　and　Ptolemy；　it　did　not　find　a　single　important　champion　for　more　than　a　thousand　years　after　the　time　of　the　last　great　Alexandrian　astronomer。　The　first　man；　seemingly；　to　hark　back　to　the　Aristarchian　conception　in　the　new　scientific　era　that　was　now　dawning　was　the　noted　cardinal；　Nikolaus　of　Cusa；　who　lived　in　the　first　half　of　the　fifteenth　century；　and　was　distinguished　as　a　philosophical　writer　and　mathematician。　His　De　Docta　Ignorantia　expressly　propounds　the　doctrine　of　the　earth's　motion。　No　one；　however；　paid　the　slightest　attention　to　his　suggestion；　which；　therefore；　merely　serves　to　furnish　us　with　another　interesting　illustration　of　the　futility　of　propounding　even　a　correct　hypothesis　before　the　time　is　ripe　to　receive　itparticularly　if　the　hypothesis　is　not　fully　fortified　by　reasoning　based　on　experiment　or　observation。　The　man　who　was　destined　to　put　forward　the　theory　of　the　earth's　motion　in　a　way　to　command　attention　was　born　in　1473；　at　the　village　of　Thorn；　in　eastern　Prussia。　His　name　was　Nicholas　Copernicus。　There　is　no　more　famous　name　in　the　entire　annals　of　science　than　this；　yet　posterity　has　never　been　able　fully　to　establish　the　lineage　of　the　famous　expositor　of　the　true　doctrine　of　the　solar　system。　The　city　of　Thorn　lies　in　a　province　of　that　border　territory　which　was　then　under　control　of　Poland；　but　which　subsequently　became　a　part　of　Prussia。　It　is　claimed　that　the　aspects　of　the　city　were　essentially　German；　and　it　is　admitted　that　the　mother　of　Copernicus　belonged　to　that　race。　The　nationality　of　the　father　is　more　in　doubt；　but　it　is　urged　that　Copernicus　used　German　as　his　mother…tongue。　His　great　work　was；　of　course；　written　in　Latin；　according　to　the　custom　of　the　time；　but　it　is　said　that；　when　not　employing　that　language；　he　always　wrote　in　German。　The　disputed　nationality　of　Copernicus　strongly　suggests　that　he　came　of　a　mixed　racial　lineage；　and　we　are　reminded　again　of　the　influences　of　those　ethnical　minglings　to　which　we　have　previously　more　than　once　referred。　The　acknowledged　centres　of　civilization　towards　the　close　of　the　fifteenth　century　were　Italy　and　Spain。　Therefore；　the　birthplace　of　Copernicus　lay　almost　at　the　confines　of　civilization；　reminding　us　of　that　earlier　period　when　Greece　was　the　centre　of　culture；　but　when　the　great　Greek　thinkers　were　born　in　Asia　Minor　and　in　Italy。　As　a　young　man；　Copernicus　made　his　way　to　Vienna　to　study　medicine；　and　subsequently　he　journeyed　into　Italy　and　remained　there　many　years；　About　the　year　1500　he　held　the　chair　of　mathematics　in　a　college　at　Rome。　Subsequently　he　returned　to　his　native　land　and　passed　his　remaining　years　there；　dying　at　Domkerr；　in　Frauenburg；　East　Prussia；　in　the　year　1543。　It　would　appear　that　Copernicus　conceived　the　idea　of　the　heliocentric　system　of　the　universe　while　he　was　a　comparatively　young　man；　since　in　the　introduction　to　his　great　work；　which　he　addressed　to　Pope　Paul　III。；　he　states　that　he　has　pondered　his　system　not　merely　nine　years；　in　accordance　with　the　maxim　of　Horace；　but　well　into　the　fourth　period　of　nine　years。　Throughout　a　considerable　portion　of　this　period　the　great　work　of　Copernicus　was　in　manuscript；　but　it　was　not　published　until　the　year　of　his　death。　The　reasons　for　the　delay　are　not　very　fully　established。　Copernicus　undoubtedly　taught　his　system　throughout　the　later　decades　of　his　life。　He　himself　tells　us　that　he　had　even　questioned　whether　it　were　not　better　for　him　to　confine　himself　to　such　verbal　teaching；　following　thus　the　example　of　Pythagoras。　Just　as　his　life　was　drawing　to　a　close；　he　decided　to　pursue　the　opposite　course；　and　the　first　copy　of　his　work　is　said　to　have　been　placed　in　his　hands　as　he　lay　on　his　deathbed。　The　violent　opposition　which　the　new　system　met　from　ecclesiastical　sources　led　subsequent　commentators　to　suppose　that　Copernicus　had　delayed　publication　of　his　work　through　fear　of　the　church　authorities。　There　seems；　however；　to　be　no　direct　evidence　for　this　opinion。　It　has　been　thought　significant　that　Copernicus　addressed　his　work　to　the　pope。　It　is；　of　course；　quite　conceivable　that　the　aged　astronomer　might　wish　by　this　means　to　demonstrate　that　he　wrote　in　no　spirit　of　hostility　to　the　church。　His　address　to　the　pope　might　have　been　considered　as　a　desirable　shield　precisely　because　the　author　recognized　that　his　work　must　needs　meet　with　ecclesiastical　criticism。　Be　that　as　it　may；　Copernicus　was　removed　by　death　from　the　danger　of　attack；　and　it　remained　for　his　disciples　of　a　later　generation　to　run　the　gauntlet　of　criticism　and　suffer　the　charges　of　heresy。　The　work　of　Copernicus；　published　thus　in　the　year　1543　at　Nuremberg；　bears　the　title　De　Orbium　Coelestium　Revolutionibus。　It　is　not　necessary　to　go　into　details　as　to　the　cosmological　system　which　Copernicus　advocated；　since　it　is　familiar　to　every　one。　In　a　word；　he　supposed　the　sun　to　be　the　centre　of　all　the　planetary　motions；　the　earth　taking　its　place　among　the　other　planets；　the　list　of　which；　as　known　at　that　time；　comprised　Mercury；　Venus；　the　Earth；　Mars；　Jupiter；　and　Saturn。　The　fixed　stars　were　alleged　to　be　stationary；　and　it　was　necessary　to　suppose　that　they　are　almost　infinitely　distant；　inasmuch　as　they　showed　to　the　observers　of　that　time　no　parallax；　that　is　to　say；　they　preserved　the　same　apparent　position　when　viewed　from　the　opposite　points　of　the　earth's　orbit。　But　let　us　allow　Copernicus　to　speak　for　himself　regarding　his　system；　His　exposition　is　full　of　interest。　We　quote　first　the　introduction　just　referred　to；　in　which　appeal　is　made　directly　to　the　pope。　〃I　can　well　believe；　most　holy　father；　that　certain　people；　when　they　hear　of　my　attributing　motion　to　the　earth　in　these　books　of　mine；　will　at　once　declare　that　such　an　opinion　ought　to　be　rejected。　Now；　my　own　theories　do　not　please　me　so　much　as　not　to　consider　what　others　may　judge　of　them。　Accordingly；　when　I　began　to　reflect　upon　what　those　persons　who　accept　the　stability　of　the　earth；　as　confirmed　by　the　opinion　of　many　centuries；　would　say　when　I　claimed　that　the　earth　moves；　I　hesitated　for　a　long　time　as　to　whether　I　should　publish　that　which　I　have　written　to　demonstrate　its　motion；　or　whether　it　would　not　be　better　to　follow　the　example　of　the　Pythagoreans；　who　used　to　hand　down　the　secrets　of　philosophy　to　their　relatives　and　friends　only　in　oral　form。　As　I　well　considered　all　this；　I　was　almost　impelled　to　put　the　finished　work　wholly　aside；　through　the　scorn　I　had　reason　to　anticipate　on　account　of　the