on sense and the sensible-第2章

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as　to　be　imperceptible　to　us；　we　should　have　expected　that　in　the



daytime　the　light　of　the　sun　should　be　quenched　when　rain　falls；　and



that　darkness　should　prevail　in　frosty　weather。　Flame；　for　example；



and　ignited　bodies　are　subject　to　such　extinction；　but　experience



shows　that　nothing　of　this　sort　happens　to　the　sunlight。



　　Empedocles　at　times　seems　to　hold　that　vision　is　to　be　explained



as　above　stated　by　light　issuing　forth　from　the　eye；　e。g。　in　the



following　passage：…







　　　　　　　　As　when　one　who　purposes　going　abroad　prepares　a　lantern；



　　　　　　　　A　gleam　of　fire　blazing　through　the　stormy　night；



　　　　　　　　Adjusting　thereto；　to　screen　it　from　all　sorts　of　winds；



　　　　　　　　　　　　　　　　transparent　sides；



　　　　　　　　Which　scatter　the　breath　of　the　winds　as　they　blow；



　　　　　　　　While；　out　through　them　leaping；　the　fire；



　　　　　　　　　　　　　　　　i。e。　all　the　more　subtile　part　of　this；



　　　　　　　　Shines　along　his　threshold　old　incessant　beams：



　　　　　　　　So　＇Divine　love＇　embedded　the　round　〃lens〃；　＇viz。＇



　　　　　　　　　　　　　　　　the　primaeval　fire　fenced　within　the　membranes；



　　　　　　　　In　＇its　own＇　delicate　tissues；



　　　　　　　　And　these　fended　off　the　deep　surrounding　flood；



　　　　　　　　While　leaping　forth　the　fire；　i。e。　all　its　more　subtile　part…。







　　Sometimes　he　accounts　for　vision　thus；　but　at　other　times　he



explains　it　by　emanations　from　the　visible　objects。



　　Democritus；　on　the　other　hand；　is　right　in　his　opinion　that　the



eye　is　of　water；　not；　however；　when　he　goes　on　to　explain　seeing　as



mere　mirroring。　The　mirroring　that　takes　place　in　an　eye　is　due　to　the



fact　that　the　eye　is　smooth；　and　it　really　has　its　seat　not　in　the　eye



which　is　seen；　but　in　that　which　sees。　For　the　case　is　merely　one　of



reflexion。　But　it　would　seem　that　even　in　his　time　there　was　no



scientific　knowledge　of　the　general　subject　of　the　formation　of　images



and　the　phenomena　of　reflexion。　It　is　strange　too；　that　it　never



occurred　to　him　to　ask　why；　if　his　theory　be　true；　the　eye　alone　sees；



while　none　of　the　other　things　in　which　images　are　reflected　do　so。



　　True；　then；　the　visual　organ　proper　is　composed　of　water；　yet　vision



appertains　to　it　not　because　it　is　so　composed；　but　because　it　is



translucent…　a　property　common　alike　to　water　and　to　air。　But　water



is　more　easily　confined　and　more　easily　condensed　than　air；



wherefore　it　is　that　the　pupil；　i。e。　the　eye　proper；　consists　of



water。　That　it　does　so　is　proved　by　facts　of　actual　experience。　The



substance　which　flows　from　eyes　when　decomposing　is　seen　to　be



water；　and　this　in　undeveloped　embryos　is　remarkably　cold　and



glistening。　In　sanguineous　animals　the　white　of　the　eye　is　fat　and



oily；　in　order　that　the　moisture　of　the　eye　may　be　proof　against



freezing。　Wherefore　the　eye　is　of　all　parts　of　the　body　the　least



sensitive　to　cold：　no　one　ever　feels　cold　in　the　part　sheltered　by　the



eyelids。　The　eyes　of　bloodless　animals　are　covered　with　a　hard　scale



which　gives　them　similar　protection。



　　It　is；　to　state　the　matter　generally；　an　irrational　notion　that



the　eye　should　see　in　virtue　of　something　issuing　from　it；　that　the



visual　ray　should　extend　itself　all　the　way　to　the　stars；　or　else　go



out　merely　to　a　certain　point；　and　there　coalesce；　as　some　say；　with



rays　which　proceed　from　the　object。　It　would　be　better　to　suppose　this



coalescence　to　take　place　in　the　fundament　of　the　eye　itself。　But　even



this　would　be　mere　trifling。　For　what　is　meant　by　the　'coalescence'　of



light　with　light？　Or　how　is　it　possible？　Coalescence　does　not　occur



between　any　two　things　taken　at　random。　And　how　could　the　light　within



the　eye　coalesce　with　that　outside　it？　For　the　environing　membrane



comes　between　them。



　　That　without　light　vision　is　impossible　has　been　stated　elsewhere；



but；　whether　the　medium　between　the　eye　and　its　objects　is　air　or



light；　vision　is　caused　by　a　process　through　this　medium。



　　Accordingly；　that　the　inner　part　of　the　eye　consists　of　water　is



easily　intelligible；　water　being　translucent。



　　Now；　as　vision　outwardly　is　impossible　without　＇extra…organic＇



light；　so　also　it　is　impossible　inwardly　＇without　light　within　the



organ＇。　There　must；　therefore；　be　some　translucent　medium　within　the



eye；　and；　as　this　is　not　air；　it　must　be　water。　The　soul　or　its



perceptive　part　is　not　situated　at　the　external　surface　of　the　eye；



but　obviously　somewhere　within：　whence　the　necessity　of　the　interior



of　the　eye　being　translucent；　i。e。　capable　of　admitting　light。　And



that　it　is　so　is　plain　from　actual　occurrences。　It　is　matter　of



experience　that　soldiers　wounded　in　battle　by　a　sword　slash　on　the



temple；　so　inflicted　as　to　sever　the　passages　of　＇i。e。　inward　from＇



the　eye；　feel　a　sudden　onset　of　darkness；　as　if　a　lamp　had　gone　out；



because　what　is　called　the　pupil；　i。e。　the　translucent；　which　is　a



sort　of　inner　lamp；　is　then　cut　off　＇from　its　connexion　with　the



soul＇。



　　Hence；　if　the　facts　be　at　all　as　here　stated；　it　is　clear　that…　if



one　should　explain　the　nature　of　the　sensory　organs　in　this　way；



i。e。　by　correlating　each　of　them　with　one　of　the　four　elements；…　we



must　conceive　that　the　part　of　the　eye　immediately　concerned　in　vision



consists　of　water；　that　the　part　immediately　concerned　in　the



perception　of　sound　consists　of　air；　and　that　the　sense　of　smell



consists　of　fire。　（I　say　the　sense　of　smell；　not　the　organ。）　For　the



organ　of　smell　is　only　potentially　that　which　the　sense　of　smell；　as



realized；　is　actually；　since　the　object　of　sense　is　what　causes　the



actualization　of　each　sense；　so　that　it　（the　sense）　must　（at　the



instant　of　actualization）　be　（actually）　that　which　before　（the



moment　of　actualization）　it　was　potentially。　Now；　odour　is　a



smoke…like　evaporation；　and　smoke…like　evaporation　arises　from　fire。



This　also　helps　us　to　understand　why　the　olfactory　organ　has　its



proper　seat　in　the　environment　of　the　brain；　for　cold　matter　is



potentially　hot。　In　the　same　way　must　the　genesis　of　the　eye　be



explained。　Its　structure　is　an　offshoot　from　the　brain；　because　the



latter　is　the　moistest　and　coldest　of　all　the　bodily　parts。



　　The　organ　of　touch　proper　consists　of　earth；　and　the　faculty　of



taste　is　a　particular　form　of　touch。　This　explains　why　the　sensory



organ　of　both　touch　and　taste　is　closely　related　to　the　heart。　For　the



heart　as　being　the　hottest　of　all　the　bodily　parts；　is　the



counterpoise　of　the　brain。



　　This　then　is　the　way　in　which　the　characteristics　of　the　bodily



organs　of　sense　must　be　determined。



　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　3







　　Of　the　sensibles　corresponding　to　each　sensory　organ；　viz。　colour；



sound；　odour；　savour；　touch；　we　have　treated　in　On　the　Soul　in　general



terms；　having　there　determined　what　their　function　is；　and　what　is



implied　in　their　becoming　actualized　in　relation　to　their　respective



organs。　We　must　next　consider　what　account　we　are　to　give　of　any　one



of　them；　what；　for　example；　we　should　say　colour　is；　or　sound；　or



odour；　or　savour；　and　so　also　respecting　＇the　object　of＇　touch。　We



begin　with　colour。



　　Now；　each　of　them　may　be　spoken　of　from　two　points　of　view；　i。e。



either　as　actual　or　as　potential。　We　have　in　On　the　Soul　explained



in　what　sense　the　colour；　or　sound；　regarded　as　actualized　＇for



sensation＇　is　the　same　as；　and　in　what　sense　it　is　different　from；　the



correlative　sensation；　the　actual　seeing　or　hearing。　The　point　of



our　present　discussion　is；　therefore；　to　determine　what　each



sensible　object　must　be　in　itself；　in　order　to　be　perceived　as　it　is



in　actual　consciousness。



　　We　have　already　in　On　the　Soul　stated　of　Light　that　it　is　the　colour



of　the　Translucent；　＇being　so　related　to　it＇　incidentally；　for



whenever　a　fiery　element　is　in　a　translucent　medium　presence　there



is　Light；　while　the　privation　of　it　is　Darkness。　But　the