the critique of practical reason- 第23部分

cal　which　might　slip　into　our　maxims　as　a　determining　principle　of　the　will　can　be　detected　at　once　by　the　feeling　of　pleasure　or　pain　which　necessarily　attaches　to　it　as　exciting　desire；　whereas　pure　practical　reason　positively　refuses　to　admit　this　feeling　into　its　principle　as　a　condition。　The　heterogeneity　of　the　determining　principles　（the　empirical　and　rational）　is　clearly　detected　by　this　resistance　of　a　practically　legislating　reason　against　every　admixture　of　inclination；　and　by　a　peculiar　kind　of　sentiment；　which；　however；　does　not　precede　the　legislation　of　the　practical　reason；　but；　on　the　contrary；　is　produced　by　this　as　a　constraint；　namely；　by　the　feeling　of　a　respect　such　as　no　man　has　for　inclinations　of　whatever　kind　but　for　the　law　only；　and　it　is　detected　in　so　marked　and　prominent　a　manner　that　even　the　most　uninstructed　cannot　fail　to　see　at　once　in　an　example　presented　to　him；　that　empirical　principles　of　volition　may　indeed　urge　him　to　follow　their　attractions；　but　that　he　can　never　be　expected　to　obey　anything　but　the　pure　practical　law　of　reason　alone。　　　The　distinction　between　the　doctrine　of　happiness　and　the　doctrine　of　morality；　in　the　former　of　which　empirical　principles　constitute　the　entire　foundation；　while　in　the　second　they　do　not　form　the　smallest　part　of　it；　is　the　first　and　most　important　office　of　the　Analytic　of　pure　practical　reason；　and　it　must　proceed　in　it　with　as　much　exactness　and；　so　to　speak；　scrupulousness；　as　any　geometer　in　his　work。　The　philosopher；　however；　has　greater　difficulties　to　contend　with　here　（as　always　in　rational　cognition　by　means　of　concepts　merely　without　construction）；　because　he　cannot　take　any　intuition　as　a　foundation　（for　a　pure　noumenon）。　He　has；　however；　this　advantage　that；　like　the　chemist；　he　can　at　any　time　make　an　experiment　with　every　man's　practical　reason　for　the　purpose　of　distinguishing　the　moral　（pure）　principle　of　determination　from　the　empirical；　namely；　by　adding　the　moral　law　（as　a　determining　principle）　to　the　empirically　affected　will　（e。g。；　that　of　the　man　who　would　be　ready　to　lie　because　he　can　gain　something　thereby）。　It　is　as　if　the　analyst　added　alkali　to　a　solution　of　lime　in　hydrochloric　acid；　the　acid　at　once　forsakes　the　lime；　combines　with　the　alkali；　and　the　lime　is　precipitated。　just　in　the　same　way；　if　to　a　man　who　is　otherwise　honest　（or　who　for　this　occasion　places　himself　only　in　thought　in　the　position　of　an　honest　man）；　we　present　the　moral　law　by　which　he　recognises　the　worthlessness　of　the　liar；　his　practical　reason　（in　forming　a　judgement　of　what　ought　to　be　done）　at　once　forsakes　the　advantage；　combines　with　that　which　maintains　in　him　respect　for　his　own　person　（truthfulness）；　and　the　advantage　after　it　has　been　separated　and　washed　from　every　particle　of　reason　（which　is　altogether　on　the　side　of　duty）　is　easily　weighed　by　everyone；　so　that　it　can　enter　into　combination　with　reason　in　other　cases；　only　not　where　it　could　be　opposed　to　the　moral　law；　which　reason　never　forsakes；　but　most　closely　unites　itself　with。　　　But　it　does　not　follow　that　this　distinction　between　the　principle　of　happiness　and　that　of　morality　is　an　opposition　between　them；　and　pure　practical　reason　does　not　require　that　we　should　renounce　all　claim　to　happiness；　but　only　that　the　moment　duty　is　in　question　we　should　take　no　account　of　happiness。　It　may　even　in　certain　respects　be　a　duty　to　provide　for　happiness；　partly；　because　（including　skill；　wealth；　riches）　it　contains　means　for　the　fulfilment　of　our　duty；　partly；　because　the　absence　of　it　（e。g。；　poverty）　implies　temptations　to　transgress　our　duty。　But　it　can　never　be　an　immediate　duty　to　promote　our　happiness；　still　less　can　it　be　the　principle　of　all　duty。　Now；　as　all　determining　principles　of　the　will；　except　the　law　of　pure　practical　reason　alone　（the　moral　law）；　are　all　empirical　and；　therefore；　as　such；　belong　to　the　principle　of　happiness；　they　must　all　be　kept　apart　from　the　supreme　principle　of　morality　and　never　be　incorporated　with　it　as　a　condition；　since　this　would　be　to　destroy　all　moral　worth　just　as　much　as　any　empirical　admixture　with　geometrical　principles　would　destroy　the　certainty　of　mathematical　evidence；　which　in　Plato's　opinion　is　the　most　excellent　thing　in　mathematics；　even　surpassing　their　utility。　　　Instead；　however；　of　the　deduction　of　the　supreme　principle　of　pure　practical　reason；　that　is；　the　explanation　of　the　possibility　of　such　a　knowledge　a　priori；　the　utmost　we　were　able　to　do　was　to　show　that　if　we　saw　the　possibility　of　the　freedom　of　an　efficient　cause；　we　should　also　see　not　merely　the　possibility；　but　even　the　necessity；　of　the　moral　law　as　the　supreme　practical　law　of　rational　beings；　to　whom　we　attribute　freedom　of　causality　of　their　will；　because　both　concepts　are　so　inseparably　united　that　we　might　define　practical　freedom　as　independence　of　the　will　on　anything　but　the　moral　law。　But　we　cannot　perceive　the　possibility　of　the　freedom　of　an　efficient　cause；　especially　in　the　world　of　sense；　we　are　fortunate　if　only　we　can　be　sufficiently　assured　that　there　is　no　proof　of　its　impossibility；　and　are　now；　by　the　moral　law　which　postulates　it；　compelled　and　therefore　authorized　to　assume　it。　However；　there　are　still　many　who　think　that　they　can　explain　this　freedom　on　empirical　principles；　like　any　other　physical　faculty；　and　treat　it　as　a　psychological　property；　the　explanation　of　which　only　requires　a　more　exact　study　of　the　nature　of　the　soul　and　of　the　motives　of　the　will；　and　not　as　a　transcendental　predicate　of　the　causality　of　a　being　that　belongs　to　the　world　of　sense　（which　is　really　the　point）。　They　thus　deprive　us　of　the　grand　revelation　which　we　obtain　through　practical　reason　by　means　of　the　moral　law；　the　revelation；　namely；　of　a　supersensible　world　by　the　realization　of　the　otherwise　transcendent　concept　of　freedom；　and　by　this　deprive　us　also　of　the　moral　law　itself；　which　admits　no　empirical　principle　of　determination。　Therefore　it　will　be　necessary　to　add　something　here　as　a　protection　against　this　delusion　and　to　exhibit　empiricism　in　its　naked　superficiality。　　　The　notion　of　causality　as　physical　necessity；　in　opposition　to　the　same　notion　as　freedom；　concerns　only　the　existence　of　things　so　far　as　it　is　determinable　in　time；　and；　consequently；　as　phenomena；　in　opposition　to　their　causality　as　things　in　themselves。　Now　if　we　take　the　attributes　of　existence　of　things　in　time　for　attributes　of　things　in　themselves　（which　is　the　common　view）；　then　it　is　impossible　to　reconcile　the　necessity　of　the　causal　relation　with　freedom；　they　are　contradictory。　For　from　the　former　it　follows　that　every　event；　and　consequently　every　action　that　takes　place　at　a　certain　point　of　time；　is　a　necessary　result　of　what　existed　in　time　preceding。　Now　as　time　past　is　no　longer　in　my　power；　hence　every　action　that　I　perform　must　be　the　necessary　result　of　certain　determining　grounds　which　are　not　in　my　power；　that　is；　at　the　moment　in　which　I　am　acting　I　am　never　free。　Nay；　even　if　I　assume　that　my　whole　existence　is　independent　on　any　foreign　cause　（for　instance；　God）；　so　that　the　determining　principles　of　my　causality；　and　even　of　my　whole　existence；　were　not　outside　myself；　yet　this　would　not　in　the　least　transform　that　physical　necessity　into　freedom。　For　at　every　moment　of　time　I　am　still　under　the　necessity　of　being　determined　to　action　by　that　which　is　not　in　my　power；　and　the　series　of　events　infinite　a　parte　priori；　which　I　only　continue　according　to　a　pre…determined　order　and　could　never　begin　of　myself；　would　be　a　continuous　physical　chain；　and　therefore　my　causality　would　never　be　freedom。　　　If；　then；　we　would　attribute　freedom　to　a　being　whose　existence　is　determined　in　time；　we　cannot　except　him　from　the　law　of　necessity　as　to　all　events　in　his　existence　and；　consequently；　as　to　his　actions　also；　for　that　would　be　to　hand　him　over　to　blind　chance。　Now　as　this　law　inevitably　applies　to　all　the　causality　of　things；　so　far　as　their　existence　is　determinable　in　time；　it　follows　that　if　this　were　the　mode　in　which　we　had　also　to　conceive　the　existence　of　these　things　in　themselves；　freedom　must　be　rejected　as　a　vain　and　impossible　conception。　Consequently；　if　we　would　still　save　it；　no　other　way　remains　but　to　consider　that　the　existence　of　a　thing；　so　far　as　it　is　determinable　in　time；　and　therefore　its　causality；　according　to　the　law　of　physical　necessity；　belong　to　appearance；　and　to　attribute　freedom　to　the　same　being　as　a　thing　in　itself。　This　is　certainly　inevitable；　if　we　would　retain　both　these　contradictory　concepts　together；　but　in　application；　when　we　try　to　explain　their　combination　in　one　and　the　same　action；　great　difficulties　present　themselves　which　seem　to　render　such　a　combination　impracticable。　　　When　I　say　of　a　man　who　commits　a　theft　that；　by　the　law　of　causality；　this　deed　is　a　necessary　result　of　the　determining　causes　in　preceding　time；　then　it　was　impossible　that　it　could　not　have　happened；　how　then　can　the　judgement；　according　to　the　moral　law；　make　any　change；　and　suppose　that　it　could　have　been　omitted；　because　the　law　says　that　it　ought　to　have　been　omitted；　that　is；　how　can　a　man　be　called　quite　free　at　the　same　moment；