the critique of pure reason- 第101部分

earth；　pure　water；　or　pure　air；　is　not　to　be　discovered。　And　yet　we

require　these　conceptions　（which　have　their　origin　in　the　reason；　so

far　as　regards　their　absolute　purity　and　completeness）　for　the　purpose

of　determining　the　share　which　each　of　these　natural　causes　has　in

every　phenomenon。　Thus　the　different　kinds　of　matter　are　all　ref　erred

to　earths；　as　mere　weight；　to　salts　and　inflammable　bodies；　as　pure

force；　and　finally；　to　water　and　air；　as　the　vehicula　of　the　former；

or　the　machines　employed　by　them　in　their　operations…　for　the

purpose　of　explaining　the　chemical　action　and　reaction　of　bodies　in

accordance　with　the　idea　of　a　mechanism。　For；　although　not　actually　so

expressed；　the　influence　of　such　ideas　of　reason　is　very　observable　in

the　procedure　of　natural　philosophers。

　　If　reason　is　the　faculty　of　deducing　the　particular　from　the

general；　and　if　the　general　be　certain　in　se　and　given；　it　is　only

necessary　that　the　judgement　should　subsume　the　particular　under　the

general；　the　particular　being　thus　necessarily　determined。　I　shall

term　this　the　demonstrative　or　apodeictic　employment　of　reason。　If；

however；　the　general　is　admitted　as　problematical　only；　and　is　a

mere　idea；　the　particular　case　is　certain；　but　the　universality　of　the

rule　which　applies　to　this　particular　case　remains　a　problem。

Several　particular　cases；　the　certainty　of　which　is　beyond　doubt；

are　then　taken　and　examined；　for　the　purpose　of　discovering　whether

the　rule　is　applicable　to　them；　and　if　it　appears　that　all　the

particular　cases　which　can　be　collected　follow　from　the　rule；　its

universality　is　inferred；　and　at　the　same　time；　all　the　causes　which

have　not；　or　cannot　be　presented　to　our　observation；　are　concluded

to　be　of　the　same　character　with　those　which　we　have　observed。　This

I　shall　term　the　hypothetical　employment　of　the　reason。

　　The　hypothetical　exercise　of　reason　by　the　aid　of　ideas　employed

as　problematical　conceptions　is　properly　not　constitutive。　That　is

to　say；　if　we　consider　the　subject　strictly；　the　truth　of　the　rule；

which　has　been　employed　as　an　hypothesis；　does　not　follow　from　the　use

that　is　made　of　it　by　reason。　For　how　can　we　know　all　the　possible

cases　that　may　arise？　some　of　which　may；　however；　prove　exceptions

to　the　universality　of　the　rule。　This　employment　of　reason　is　merely

regulative；　and　its　sole　aim　is　the　introduction　of　unity　into　the

aggregate　of　our　particular　cognitions；　and　thereby　the

approximating　of　the　rule　to　universality。

　　The　object　of　the　hypothetical　employment　of　reason　is　therefore　the

systematic　unity　of　cognitions；　and　this　unity　is　the　criterion　of　the

truth　of　a　rule。　On　the　other　hand；　this　systematic　unity…　as　a　mere

idea…　is　in　fact　merely　a　unity　projected；　not　to　be　regarded　as

given；　but　only　in　the　light　of　a　problem…　a　problem　which　serves；

however；　as　a　principle　for　the　various　and　particular　exercise　of　the

understanding　in　experience；　directs　it　with　regard　to　those　cases

which　are　not　presented　to　our　observation；　and　introduces　harmony　and

consistency　into　all　its　operations。

　　All　that　we　can　be　certain　of　from　the　above　considerations　is

that　this　systematic　unity　is　a　logical　principle；　whose　aim　is　to

assist　the　understanding；　where　it　cannot　of　itself　attain　to　rules；

by　means　of　ideas；　to　bring　all　these　various　rules　under　one

principle；　and　thus　to　ensure　the　most　complete　consistency　and

connection　that　can　be　attained。　But　the　assertion　that　objects　and

the　understanding　by　which　they　are　cognized　are　so　constituted　as

to　be　determined　to　systematic　unity；　that　this　may　be　postulated　a

priori；　without　any　reference　to　the　interest　of　reason；　and　that　we

are　justified　in　declaring　all　possible　cognitions…　empirical　and

others…　to　possess　systematic　unity；　and　to　be　subject　to　general

principles　from　which；　notwithstanding　their　various　character；　they

are　all　derivable　such　an　assertion　can　be　founded　only　upon　a

transcendental　principle　of　reason；　which　would　render　this　systematic

unity　not　subjectively　and　logically…　in　its　character　of　a　method；

but　objectively　necessary。

　　We　shall　illustrate　this　by　an　example。　The　conceptions　of　the

understanding　make　us　acquainted；　among　many　other　kinds　of　unity；

with　that　of　the　causality　of　a　substance；　which　is　termed　power。

The　different　phenomenal　manifestations　of　the　same　substance　appear

at　first　view　to　be　so　very　dissimilar　that　we　are　inclined　to

assume　the　existence　of　just　as　many　different　powers　as　there　are

different　effects…　as；　in　the　case　of　the　human　mind；　we　have　feeling；

consciousness；　imagination；　memory；　wit；　analysis；　pleasure；　desire

and　so　on。　Now　we　are　required　by　a　logical　maxim　to　reduce　these

differences　to　as　small　a　number　as　possible；　by　comparing　them　and

discovering　the　hidden　identity　which　exists。　We　must　inquire；　for

example；　whether　or　not　imagination　（connected　with　consciousness）；

memory；　wit；　and　analysis　are　not　merely　different　forms　of

understanding　and　reason。　The　idea　of　a　fundamental　power；　the

existence　of　which　no　effort　of　logic　can　assure　us　of；　is　the　problem

to　be　solved；　for　the　systematic　representation　of　the　existing

variety　of　powers。　The　logical　principle　of　reason　requires　us　to

produce　as　great　a　unity　as　is　possible　in　the　system　of　our

cognitions；　and　the　more　the　phenomena　of　this　and　the　other　power　are

found　to　be　identical；　the　more　probable　does　it　become；　that　they　are

nothing　but　different　manifestations　of　one　and　the　same　power；

which　may　be　called；　relatively　speaking；　a　fundamental　power。　And

so　with　other　cases。

　　These　relatively　fundamental　powers　must　again　be　compared　with　each

other；　to　discover；　if　possible；　the　one　radical　and　absolutely

fundamental　power　of　which　they　are　but　the　manifestations。　But　this

unity　is　purely　hypothetical。　It　is　not　maintained；　that　this　unity

does　really　exist；　but　that　we　must；　in　the　interest　of　reason；　that

is；　for　the　establishment　of　principles　for　the　various　rules

presented　by　experience；　try　to　discover　and　introduce　it；　so　far　as

is　practicable；　into　the　sphere　of　our　cognitions。

　　But　the　transcendental　employment　of　the　understanding　would　lead　us

to　believe　that　this　idea　of　a　fundamental　power　is　not　problematical；

but　that　it　possesses　objective　reality；　and　thus　the　systematic　unity

of　the　various　powers　or　forces　in　a　substance　is　demanded　by　the

understanding　and　erected　into　an　apodeictic　or　necessary　principle。

For；　without　having　attempted　to　discover　the　unity　of　the　various

powers　existing　in　nature；　nay；　even　after　all　our　attempts　have

failed；　we　notwithstanding　presuppose　that　it　does　exist；　and　may

be；　sooner　or　later；　discovered。　And　this　reason　does；　not　only；　as　in

the　case　above　adduced；　with　regard　to　the　unity　of　substance；　but

where　many　substances；　although　all　to　a　certain　extent　homogeneous；

are　discoverable；　as　in　the　case　of　matter　in　general。　Here　also

does　reason　presuppose　the　existence　of　the　systematic　unity　of

various　powers…　inasmuch　as　particular　laws　of　nature　are

subordinate　to　general　laws；　and　parsimony　in　principles　is　not　merely

an　economical　principle　of　reason；　but　an　essential　law　of　nature。

　　We　cannot　understand；　in　fact；　how　a　logical　principle　of　unity

can　of　right　exist；　unless　we　presuppose　a　transcendental　principle；

by　which　such　a　systematic　unit…　as　a　property　of　objects

themselves…　is　regarded　as　necessary　a　priori。　For　with　what　right　can

reason；　in　its　logical　exercise；　require　us　to　regard　the　variety　of

forces　which　nature　displays；　as　in　effect　a　disguised　unity；　and　to

deduce　them　from　one　fundamental　force　or　power；　when　she　is　free　to

admit　that　it　is　just　as　possible　that　all　forces　should　be

different　in　kind；　and　that　a　systematic　unity　is　not　conformable　to

the　design　of　nature？　In　this　view　of　the　case；　reason　would　be

proceeding　in　direct　opposition　to　her　own　destination；　by　setting

as　an　aim　an　idea　which　entirely　conflicts　with　the　procedure　and

arrangement　of　nature。　Neither　can　we　assert　that　reason　has

previously　inferred　this　unity　from　the　contingent　nature　of

phenomena。　For　the　law　of　reason　which　requires　us　to　seek　for　this

unity　is　a　necessary　law；　inasmuch　as　without　it　we　should　not　possess

a　faculty　of　reason；　nor　without　reason　a　consistent　and

self…accordant　mode　of　employing　the　understanding；　nor；　in　the

absence　of　this；　any　proper　and　sufficient　criterion　of　empirical

truth。　In　relation　to　this　criterion；　therefore；　we　must　suppose　the

idea　of　the　systematic　unity　of　nature　to　possess　objective　validity

and　necessity。

　　We　find　this　transcendental　presupposition　lurking　in　different

forms　in　the　principles　of　philosophers；　although　they　have　neither

recognized　it　nor　confessed　to　themselves　its　presence。　That　the

diversities　of　individual　things　do　not　exclude　identity　of　species；

that　the　various　species　must　be　considered　as　merely　different

determinations　of　a　few　genera；　and　these　again　as　divisions　of

still　higher　races；　and　so　on…　that；　accordingly；　a　certain　systematic

unity　of　all　possible　empirical　conceptions；　in　so　far　as　they　can

be　deduced　from　higher　and　more　general　conceptions；　must　be　sought

for；　is　a　scholastic　maxim　or　logical　principle；　without　which

reason　could　not　be　employed　by　us。　For　we　can　infer　the　particular

from　the　general；　only　in　so　far　as　general　properties　of　things

constitute　the　foundation　upon　which　the　particular　rest。

　　That　the　same　unity　exists　in　nature　is　presupposed　by

philosophers　in　the　well…known　scholastic　maxim；　which　forbids　us

unnecessarily　to　augment　the　number　of　entities　or　principles　（entia

praeter　necessitatem　non　esse　multiplicanda）。　This　maxim　asserts

that　nature　herself　assists　in　the　establishment　of　this　unity　of

reason；　and　that　the　seemingly　infinite　diversity　of　phenomena

should　not　deter　us　from　the　expectation　of　discove