rom　which　the　spirit　of　criticism　derived　its　nourishmentthe　metaphysical　and　dialectical　discussions　practiced　by　the　Eleatic　philosophers；　and　the　semi…historical　method　which　was　applied　to　the　myths　by　Hecataeus　and　Herodotus。　A　third　source　is　to　be　traced　to　the　schools　of　the　physicians。　These　aimed　at　eliminating　the　arbitrary　element　from　the　view　and　knowledge　of　nature；　the　beginnings　of　which　were　bound　up　with　it　in　a　greater　or　less　degree；　though　practically　without　exception　and　by　the　force　of　an　inner　necessity。　A　knowledge　of　medicine　was　destined　to　correct　that　defect；　and　we　shall　mark　the　growth　of　its　most　precious　fruits　in　the　increased　power　of　observation　and　the　counterpoise　it　offered　to　hasty　generalizations；　as　well　as　in　the　confidence　which　learnt　to　reject　untenable　fictions；　whether　produced　by　luxuriant　imagination　or　by　a　priori　speculations；　on　the　similar　ground　of　self…reliant　sense…perception。〃＇3＇
  ＇3＇　Gomperz：　Greek　Thinkers；　Vol。　I；　p。　276。
  The　nature　philosophers　of　the　Ionian　days　did　not　contribute　much　to　medicine　proper；　but　their　spirit　and　their　outlook　upon　nature　influenced　its　students　profoundly。　　Their　bold　generalizations　on　the　nature　of　matter　and　of　the　elements　are　still　the　wonder　of　chemists。　　We　may　trace　to　one　of　them；　Anaximenes；　who　regarded　air　as　the　primary　principle；　the　doctrine　of　the　〃pneuma；〃　or　the　breath　of　lifethe　psychic　force　which　animates　the　body　and　leaves　it　at　death〃Our　soul　being　air；　holds　us　together。〃　Of　another；　the　famous　Heraclitus；　possibly　a　physician；　the　existing　fragments　do　not　relate　specially　to　medicine；　but　to　the　philosopher　of　fire　may　be　traced　the　doctrine　of　heat　and　moisture；　and　their　antitheses；　which　influenced　practice　for　many　centuries。　　There　is　evidence　in　the　Hippocratic　treatise　peri　sarkwn　of　an　attempt　to　apply　this　doctrine　to　the　human　body。　The　famous　expression；　panta　rhei；〃all　things　are　flowing；〃expresses　the　incessant　flux　in　which　he　believed　and　in　which　we　know　all　matter　exists。　　No　one　has　said　a　ruder　thing　of　the　profession；　for　an　extant　fragment　reads：　　〃。　。　。　physicians；　who　cut；　burn；　stab；　and　rack　the　sick；　then　complain　that　they　do　not　get　any　adequate　recompense　for　it。〃＇4＇
  ＇4＇　J。　Burnet：　　Early　Greek　Philosophy；　1892；　p。　137；　Bywater's　no。　LVIII。
  The　South　Italian　nature　philosophers　contributed　much　more　to　the　science　of　medicine；　and　in　certain　of　the　colonial　towns　there　were　medical　schools　as　early　as　the　fifth　century　B。C。　The　most　famous　of　these　physician　philosophers　was　Pythagoras；　whose　life　and　work　had　an　extraordinary　influence　upon　medicine；　particularly　in　connection　with　his　theory　of　numbers；　and　the　importance　of　critical　days。　His　discovery　of　the　dependence　of　the　pitch　of　sound　on　the　length　of　the　vibrating　chord　is　one　of　the　most　fundamental　in　acoustics。　Among　the　members　of　the　school　which　he　founded　at　Crotona　were　many　physicians。　　who　carried　his　views　far　and　wide　throughout　Magna　Graecia。　　Nothing　in　his　teaching　dominated　medicine　so　much　as　the　doctrine　of　numbers；　the　sacredness　of　which　seems　to　have　had　an　enduring　fascination　for　the　medical　mind。　Many　of　the　common　diseases；　such　as　malaria；　or　typhus；　terminating　abruptly　on　special　days；　favored　this　belief。　How　dominant　it　became　and　how　persistent　you　may　judge　from　the　literature　upon　critical　days；　which　is　rich　to　the　middle　of　the　eighteenth　century。
  One　member　of　the　Crotonian　school；　Alcmaeon；　achieved　great　distinction　in　both　anatomy　and　physiology。　　He　first　recognized　the　brain　as　the　organ　of　the　mind；　and　made　careful　dissections　of　the　nerves；　which　he　traced　to　the　brain。　He　described　the　optic　nerves　and　the　Eustachian　tubes；　made　correct　observations　upon　vision；　and　refuted　the　common　view　that　the　sperma　came　from　the　spinal　cord。　　He　suggested　the　definition　of　health　as　the　maintenance　of　equilibrium；　or　an　〃isonomy〃　in　the　material　qualities　of　the　body。　Of　all　the　South　Italian　physicians　of　this　period；　the　personality　of　none　stands　out　in　stronger　outlines　than　that　of　Empedocles　of　Agrigentumphysician；　physiologist；　religious　teacher；　politician　and　poet。　　A　wonder…worker；　also；　and　magician；　he　was　acclaimed　in　the　cities　as　an　immortal　god　by　countless　thousands　desiring　oracles　or　begging　the　word　of　healing。　That　he　was　a　keen　student　of　nature　is　witnessed　by　many　recorded　observations　in　anatomy　and　physiology；　he　reasoned　that　sensations　travel　by　definite　paths　to　the　brain。　But　our　attention　must　be　confined　to　his　introduction　of　the　theory　of　the　four　elementsfire；　air；　earth　and　waterof　which；　in　varying　quantities；　all　bodies　were　made　up。　Health　depended　upon　the　due　equilibrium　of　these　primitive　substances；　disease　was　their　disturbance。　　Corresponding　to　those　were　the　four　essential　qualities　of　heat　and　cold；　moisture　and　dryness；　and　upon　this　four…fold　division　was　engrafted　by　the　later　physicians　the　doctrine　of　the　humors　which；　from　the　days　of　Hippocrates　almost　to　our　own；　dominated　medicine。　All　sorts　of　magical　powers　were　attributed　to　Empedocles。　　The　story　of　Pantheia　whom　he　called　back　to　life　after　a　thirty　days'　trance　has　long　clung　in　the　imagination。　You　remember　how　Matthew　Arnold　describes　him　in　the　well…known　poem；　〃Empedocles　on　Etna〃
  But　his　power　Swells　with　the　swelling　evil　of　this　time；　And　holds　men　mute　to　see　where　it　will　rise。　He　could　stay　swift　diseases　in　old　days；　Chain　madmen　by　the　music　of　his　lyre；　Cleanse　to　sweet　airs　the　breath　of　poisonous　streams；　And　in　the　mountain…chinks　inter　the　winds。　This　he　could　do　of　old＇5＇
  a　quotation　which　will　give　you　an　idea　of　some　of　the　powers　attributed　to　this　wonder…working　physician。
  ＇5＇　Poetical　Works　of　Matthew　Arnold；　Macmillan　&　Co。；　1898；　p。　440。
  But　of　no　one　of　the　men　of　this　remarkable　circle　have　we　such　definite　information　as　of　the　Crotonian　physician　Democedes；　whose　story　is　given　at　length　by　Herodotus；　and　his　story　has　also　the　great　importance　of　showing　that；　even　at　this　early　period；　a　well…devised　scheme　of　public　medical　service　existed　in　the　Greek　cities。　It　dates　from　the　second　half　of　the　sixth　century　B。C。fully　two　generations　before　Hippocrates。　　A　Crotonian；　Democedes　by　name；　was　found　among　the　slaves　of　Oroetes。　　Of　his　fame　as　a　physician　someone　had　heard　and　he　was　called　in　to　treat　the　dislocated　ankle　of　King　Darius。　　The　wily　Greek；　longing　for　his　home；　feared　that　if　he　confessed　to　a　knowledge　of　medicine　there　would　be　no　chance　of　escape；　but　under　threat　of　torture　he　undertook　a　treatment　which　proved　successful。　　Then　Herodotus　tells　his　storyhow；　ill　treated　at　home　in　Crotona；　Democedes　went　to　AEgina；　where　he　set　up　as　a　physician　and　in　the　second　year　the　State　of　AEgina　hired　his　services　at　the　price　of　a　talent。　In　the　third　year；　the　Athenians　engaged　him　at　100　minae；　and　in　the　fourth；　Polycrates　of　Samos　at　two　talents。　Democedes　shared　the　misfortunes　of　Polycrates　and　was　taken　prisoner　by　Oroetes。　　Then　Herodotus　tells　how　he　cured　Atossa；　the　daughter　of　Cyrus　and　wife　of　Darius；　of　a　severe　abscess　of　the　breast；　but　on　condition　that　she　help　him　to　escape；　and　she　induced　her　husband　to　send　an　expedition　of　exploration　to　Greece　under　the　guidance　of　Democedes；　but　with　the　instructions　at　all　costs　to　bring　back　the　much　prized　physician。　　From　Tarentum；　Democedes　escaped　to　his　native　city；　but　the　Persians　followed　him；　and　it　was　with　the　greatest　difficulty　that　he　escaped　from　their　hands。　Deprived　of　their　guide；　the　Persians　gave　up　the　expedition　and　sailed　for　Asia。　　In　palliation　of　his　flight；　Democedes　sent　a　message　to　Darius　that　he　was　engaged　to　the　daughter　of　Milo；　the　wrestler；　who　was　in　high　repute　with　the　King。＇6＇
  ＇6＇　The　well…known　editor　of　Herodotus；　R。　W。　Macan；　Master　of　University　College；　Oxford；　in　his　Hellenikon。　　A　Sheaf　of　Sonnets　after　Herodotus　（Oxford；　1898）　has　included　a　poem　which　may　be　quoted　in　connection　with　this　incident：
  NOSTALGY　　Atossa；　child　of　Cyrus　king　of　kings；　　healed　by　Greek　science　of　a　morbid　breast；　　gave　lord　Dareios　neither　love　nor　rest　　till　he　fulfilled　her　vain　imaginings。　　〃Sir；　show　our　Persian　folk　your　sceptre's　wings！　　Enlarge　my　sire's　and　brother's　large　bequest。　　This　learned　Greek　shall　guide　your　galleys　west；　　and　Dorian　slave…girls　grace　our　banquetings。〃　　So　said　she；　taught　of　that　o'er…artful　man；　　the　Italiote　captive；　Kroton's　Demokede；　　who　recked　not　what　of　maladies　began；　　nor　who　in　Asia　and　in　Greece　might　bleed；　　if　heso　writes　the　guileless　Thurian　　regained　his　home；　and　freedom　of　the　Mede。
  Plato　has　several　references　to　these　state　physicians；　who　were　evidently　elected　by　a　public　assembly：　　〃When　the　assembly　meets　to　elect　a　physician；〃　and　the　office　was　yearly；　for　in　〃The　Statesman〃　we　find　the　following：＇7＇　〃When　the　year　of　office　has　expired；　the　pilot；　or　physician　has　to　come　before　a　court　of　review〃　to　answer　any　charges。　The　physician　must　have　been　in　practice　for　some　time　and　attained　eminence；　before　he　was　deemed　worthy　of　the　post　of　state　physician。
  ＇7＇　Jowett：　　Dialogues　of　Plato；　3d　ed。；　Statesman；　Vol。　IV；　p。　502　（St