a history of science-1-第25章

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nth　century。　To　have　forecast　even　dimly　this　newest　phase　of　chemical　knowledge；　across　the　abyss　of　centuries；　is　indeed　a　feat　to　put　Democritus　in　the　front　rank　of　thinkers。　But　this　estimate　should　not　blind　us　to　the　fact　that　the　pre…vision　of　Democritus　was　but　a　slight　elaboration　of　a　theory　which　had　its　origin　with　another　thinker。　The　association　between　Anaxagoras　and　Democritus　cannot　be　directly　traced；　but　it　is　an　association　which　the　historian　of　ideas　should　never　for　a　moment　forget。　If　we　are　not　to　be　misled　by　mere　word…jugglery；　we　shall　recognize　the　founder　of　the　atomic　theory　of　matter　in　Anaxagoras；　its　expositors　along　slightly　different　lines　in　Leucippus　and　Democritus；　its　re…discoverer　of　the　nineteenth　century　in　Dalton。　All　in　all；　then；　just　as　Anaxagoras　preceded　Democritus　in　time；　so　must　he　take　precedence　over　him　also　as　an　inductive　thinker；　who　carried　the　use　of　the　scientific　imagination　to　its　farthest　reach。　An　analysis　of　the　theories　of　the　two　men　leads　to　somewhat　the　same　conclusion　that　might　be　reached　from　a　comparison　of　their　lives。　Anaxagoras　was　a　sceptical；　experimental　scientist；　gifted　also　with　the　prophetic　imagination。　He　reasoned　always　from　the　particular　to　the　general；　after　the　manner　of　true　induction；　and　he　scarcely　took　a　step　beyond　the　confines　of　secure　induction。　True　scientist　that　he　was；　he　could　content　himself　with　postulating　different　qualities　for　his　elements；　without　pretending　to　know　how　these　qualities　could　be　defined。　His　elements　were　by　hypothesis　invisible；　hence　he　would　not　attempt　to　visualize　them。　Democritus；　on　the　other　hand；　refused　to　recognize　this　barrier。　Where　he　could　not　know；　he　still　did　not　hesitate　to　guess。　Just　as　he　conceived　his　atom　of　a　definite　form　with　a　definite　structure；　even　so　he　conceived　that　the　atmosphere　about　him　was　full　of　invisible　spirits；　he　accepted　the　current　superstitions　of　his　time。　Like　the　average　Greeks　of　his　day；　he　even　believed　in　such　omens　as　those　furnished　by　inspecting　the　entrails　of　a　fowl。　These　chance　bits　of　biography　are　weather…　vanes　of　the　mind　of　Democritus。　They　tend　to　substantiate　our　conviction　that　Democritus　must　rank　below　Anaxagoras　as　a　devotee　of　pure　science。　But；　after　all；　such　comparisons　and　estimates　as　this　are　utterly　futile。　The　essential　fact　for　us　is　that　here；　in　the　fifth　century　before　our　era；　we　find　put　forward　the　most　penetrating　guess　as　to　the　constitution　of　matter　that　the　history　of　ancient　thought　has　to　present　to　us。　In　one　direction；　the　avenue　of　progress　is　barred；　there　will　be　no　farther　step　that　way　till　we　come　down　the　centuries　to　the　time　of　Dalton。

HIPPOCRATES　AND　GREEK　MEDICINE　These　studies　of　the　constitution　of　matter　have　carried　us　to　the　limits　of　the　field　of　scientific　imagination　in　antiquity；　let　us　now　turn　sharply　and　consider　a　department　of　science　in　which　theory　joins　hands　with　practicality。　Let　us　witness　the　beginnings　of　scientific　therapeutics。　Medicine　among　the　early　Greeks；　before　the　time　of　Hippocrates；　was　a　crude　mixture　of　religion；　necromancy；　and　mysticism。　Temples　were　erected　to　the　god　of　medicine；　aesculapius；　and　sick　persons　made　their　way；　or　were　carried；　to　these　temples；　where　they　sought　to　gain　the　favor　of　the　god　by　suitable　offerings；　and　learn　the　way　to　regain　their　health　through　remedies　or　methods　revealed　to　them　in　dreams　by　the　god。　When　the　patient　had　been　thus　cured；　he　placed　a　tablet　in　the　temple　describing　his　sickness；　and　telling　by　what　method　the　god　had　cured　him。　He　again　made　suitable　offerings　at　the　temple；　which　were　sometimes　in　the　form　of　gold　or　silver　representations　of　the　diseased　organa　gold　or　silver　model　of　a　heart；　hand；　foot；　etc。　Nevertheless；　despite　this　belief　in　the　supernatural；　many　drugs　and　healing　lotions　were　employed；　and　the　Greek　physicians　possessed　considerable　skill　in　dressing　wounds　and　bandaging。　But　they　did　not　depend　upon　these　surgical　dressings　alone；　using　with　them　certain　appropriate　prayers　and　incantations；　recited　over　the　injured　member　at　the　time　of　applying　the　dressings。　Even　the　very　early　Greeks　had　learned　something　of　anatomy。　The　daily　contact　with　wounds　and　broken　bones　must　of　necessity　lead　to　a　crude　understanding　of　anatomy　in　general。　The　first　Greek　anatomist；　however；　who　is　recognized　as　such；　is　said　to　have　been　Alcmaeon。　He　is　said　to　have　made　extensive　dissections　of　the　lower　animals；　and　to　have　described　many　hitherto　unknown　structures；　such　as　the　optic　nerve　and　the　Eustachian　canalthe　small　tube　leading　into　the　throat　from　the　ear。　He　is　credited　with　many　unique　explanations　of　natural　phenomena；　such　as；　for　example；　the　explanation　that　〃hearing　is　produced　by　the　hollow　bone　behind　the　ear；　for　all　hollow　things　are　sonorous。〃　He　was　a　rationalist；　and　he　taught　that　the　brain　is　the　organ　of　mind。　The　sources　of　our　information　about　his　work；　however；　are　unreliable。　Democedes；　who　lived　in　the　sixth　century　B。C。；　is　the　first　physician　of　whom　we　have　any　trustworthy　history。　We　learn　from　Herodotus　that　he　came　from　Croton　to　aegina；　where；　in　recognition　of　his　skill；　he　was　appointed　medical　officer　of　the　city。　From　aegina　he　was　called　to　Athens　at　an　increased　salary；　and　later　was　in　charge　of　medical　affairs　in　several　other　Greek　cities。　He　was　finally　called　to　Samos　by　the　tyrant　Polycrates；　who　reigned　there　from　about　536　to　522　B。C。　But　on　the　death　of　Polycrates；　who　was　murdered　by　the　Persians；　Democedes　became　a　slave。　His　fame　as　a　physician；　however；　had　reached　the　ears　of　the　Persian　monarch；　and　shortly　after　his　capture　he　was　permitted　to　show　his　skill　upon　King　Darius　himself。　The　Persian　monarch　was　suffering　from　a　sprained　ankle；　which　his　Egyptian　surgeons　had　been　unable　to　cure。　Democedes　not　only　cured　the　injured　member　but　used　his　influence　in　saving　the　lives　of　his　Egyptian　rivals；　who　had　been　condemned　to　death　by　the　king。　At　another　time　he　showed　his　skill　by　curing　the　queen；　who　was　suffering　from　a　chronic　abscess　of　long　standing。　This　so　pleased　the　monarch　that　he　offered　him　as　a　reward　anything　he　might　desire；　except　his　liberty。　But　the　costly　gifts　of　Darius　did　not　satisfy　him　so　long　as　he　remained　a　slave；　and　determined　to　secure　his　freedom　at　any　cost；　he　volunteered　to　lead　some　Persian　spies　into　his　native　country；　promising　to　use　his　influence　in　converting　some　of　the　leading　men　of　his　nation　to　the　Persian　cause。　Laden　with　the　wealth　that　had　been　heaped　upon　him　by　Darius；　he　set　forth　upon　his　mission；　but　upon　reaching　his　native　city　of　Croton　he　threw　off　his　mask；　renounced　his　Persian　mission；　and　became　once　more　a　free　Greek。　While　the　story　of　Democedes　throws　little　light　upon　the　medical　practices　of　the　time；　it　shows　that　paid　city　medical　officers　existed　in　Greece　as　early　as　the　fifth　and　sixth　centuries　B。C。　Even　then　there　were　different　〃schools〃　of　medicine；　whose　disciples　disagreed　radically　in　their　methods　of　treating　diseases；　and　there　were　also　specialists　in　certain　diseases；　quacks；　and　charlatans。　Some　physicians　depended　entirely　upon　external　lotions　for　healing　all　disorders；　others　were　〃hydrotherapeutists〃　or　〃bath…　physicians〃；　while　there　were　a　host　of　physicians　who　administered　a　great　variety　of　herbs　and　drugs。　There　were　also　magicians　who　pretended　to　heal　by　sorcery；　and　great　numbers　of　bone…setters；　oculists；　and　dentists。　Many　of　the　wealthy　physicians　had　hospitals；　or　clinics；　where　patients　were　operated　upon　and　treated。　They　were　not　hospitals　in　our　modern　understanding　of　the　term；　but　were　more　like　dispensaries；　where　patients　were　treated　temporarily；　but　were　not　allowed　to　remain　for　any　length　of　time。　Certain　communities　established　and　supported　these　dispensaries　for　the　care　of　the　poor。　But　anything　approaching　a　rational　system　of　medicine　was　not　established；　until　Hippocrates　of　Cos；　the　〃father　of　medicine；〃　came　upon　the　scene。　In　an　age　that　produced　Phidias；　Lysias；　Herodotus；　Sophocles；　and　Pericles；　it　seems　but　natural　that　the　medical　art　should　find　an　exponent　who　would　rise　above　superstitious　dogmas　and　lay　the　foundation　for　a　medical　science。　His　rejection　of　the　supernatural　alone　stamps　the　greatness　of　his　genius。　But；　besides　this；　he　introduced　more　detailed　observation　of　diseases；　and　demonstrated　the　importance　that　attaches　to　prognosis。　Hippocrates　was　born　at　Cos；　about　460　B。C。；　but　spent　most　of　his　life　at　Larissa；　in　Thessaly。　He　was　educated　as　a　physician　by　his　father；　and　travelled　extensively　as　an　itinerant　practitioner　for　several　years。　His　travels　in　different　climates　and　among　many　different　people　undoubtedly　tended　to　sharpen　his　keen　sense　of　observation。　He　was　a　practical　physician　as　well　as　a　theorist；　and；　withal；　a　clear　and　concise　writer。　〃Life　is　short；〃　he　says；　〃opportunity　fleeting；　judgment　difficult；　treatment　easy；　but　treatment　after　thought　is　proper　and　profitable。〃　His　knowledge　of　anatomy　was　necessarily　very　imperfect；　and　was　gained　largely　from　his　predecessors；　to　whom　he　gave　full　credit。　Dissections　of　the　human　body　were　forbidden　him；　and　he　was　obliged　to　confine　his　experimental　researches　to　operations　on　the　lower　animals。　His　knowledge　of　the　structure　and　arrangement　of　the　bones；　however；　was　fairly　accurate；　but　the　anatomy　of　the　softer　tissues；　as　he　conceived　it；　was　a　queer　jumbling　together　of　blood…vessels；　muscles；　and　tendons。　He　does　refer　to　〃nerves；〃　to　be　sure；　but　apparently　the　structures　referred　to　are　the　tendons　and　ligaments；　rather　than　the　nerves　themselves。　He　was　better　acquainted　with　the　principal　organs　in　the　cavities　of　the　body；　and　knew；　for　example；　that　the　heart　is　divided　into　four　cavities；　two　of　which　he　supposed　to　contain　blood；　and　the　other　two　air。　His　most　revolutionary　step　was　his　divorcing　of　the　supernatural　from　the　natural；　and　establishing　the　fact　that　disease　is　due　to　natural　causes　and　should　be　treated　accordingly。　The　effect　of　such　an　attitude　can　hardly　be　over…estimated。　The　establishment　of　such　a　theory　was　naturally　followed　by　a　close　observation　as　to　the　course　of　diseases　and　the　effects　of　treatment。　To　facilitate　this；　he　introduced　the　custom　of　writing　down　his　observations　as　he　made　themthe　〃clinical　history〃　of　the　case。　Such　clinical　records　are　in　use　all　over　the　world　to…day；　and　their　importance　is　so　obvious　that　it　is　almost　incomprehensible　that　they　should　have　fallen　into　disuse　shortly　after　the　time　of　Hippocrates；　and　not　brought　into　general　use　again　until　almost　two　thousand　years　later。　But　scarcely　less　important　than　his　recognition　of　disease　as　a　natural　phenomenon　was　the　importance　he　attributed　to　prognosis。　Prognosis；　in　the　sense　of　prophecy；　was　common　before　the　time　of　Hippocrates。　But　prognosis；　as　he　practised　it　and　as　we　understand　it　to…day；　is　prophecy　based　on　careful　observation　of　the　course　of　diseasessomething　more　than　superstitious　conjecture。　Although　Hippocratic　medicine　rested　on　the　belief　in　natural　causes；　nevertheless；　dogma　and　theory　held　an　important　place。　The　humoral　theory　of　disease　was　an　all…important　one；　and　so　fully　was　this