the critique of pure reason- 第102部分

reason；　and　that　the　seemingly　infinite　diversity　of　phenomena

should　not　deter　us　from　the　expectation　of　discovering　beneath　this

diversity　a　unity　of　fundamental　properties；　of　which　the　aforesaid

variety　is　but　a　more　or　less　determined　form。　This　unity；　although

a　mere　idea；　thinkers　have　found　it　necessary　rather　to　moderate　the

desire　than　to　encourage　it。　It　was　considered　a　great　step　when

chemists　were　able　to　reduce　all　salts　to　two　main　genera…　acids　and

alkalis；　and　they　regard　this　difference　as　itself　a　mere　variety；

or　different　manifestation　of　one　and　the　same　fundamental　material。

The　different　kinds　of　earths　（stones　and　even　metals）　chemists　have

endeavoured　to　reduce　to　three；　and　afterwards　to　two；　but　still；

not　content　with　this　advance；　they　cannot　but　think　that　behind　these

diversities　there　lurks　but　one　genus…　nay；　that　even　salts　and　earths

have　a　common　principle。　It　might　be　conjectured　that　this　is　merely

an　economical　plan　of　reason；　for　the　purpose　of　sparing　itself

trouble；　and　an　attempt　of　a　purely　hypothetical　character；　which；

when　successful；　gives　an　appearance　of　probability　to　the　principle

of　explanation　employed　by　the　reason。　But　a　selfish　purpose　of　this

kind　is　easily　to　be　distinguished　from　the　idea；　according　to　which

every　one　presupposes　that　this　unity　is　in　accordance　with　the　laws

of　nature；　and　that　reason　does　not　in　this　case　request；　but

requires；　although　we　are　quite　unable　to　determine　the　proper

limits　of　this　unity。

　　If　the　diversity　existing　in　phenomena…　a　diversity　not　of　form　（for

in　this　they　may　be　similar）　but　of　content…　were　so　great　that　the

subtlest　human　reason　could　never　by　comparison　discover　in　them　the

least　similarity　（which　is　not　impossible）；　in　this　case　the　logical

law　of　genera　would　be　without　foundation；　the　conception　of　a

genus；　nay；　all　general　conceptions　would　be　impossible；　and　the

faculty　of　the　understanding；　the　exercise　of　which　is　restricted　to

the　world　of　conceptions；　could　not　exist。　The　logical　principle　of

genera；　accordingly；　if　it　is　to　be　applied　to　nature　（by　which　I　mean

objects　presented　to　our　senses）；　presupposes　a　transcendental

principle。　In　accordance　with　this　principle；　homogeneity　is

necessarily　presupposed　in　the　variety　of　phenomena　（although　we　are

unable　to　determine　a　priori　the　degree　of　this　homogeneity）；

because　without　it　no　empirical　conceptions；　and　consequently　no

experience；　would　be　possible。

　　The　logical　principle　of　genera；　which　demands　identity　in

phenomena；　is　balanced　by　another　principle…　that　of　species；　which

requires　variety　and　diversity　in　things；　notwithstanding　their

accordance　in　the　same　genus；　and　directs　the　understanding　to

attend　to　the　one　no　less　than　to　the　other。　This　principle　（of　the

faculty　of　distinction）　acts　as　a　check　upon　the　reason　and　reason

exhibits　in　this　respect　a　double　and　conflicting　interest…　on　the　one

hand；　the　interest　in　the　extent　（the　interest　of　generality）　in

relation　to　genera；　on　the　other；　that　of　the　content　（the　interest　of

individuality）　in　relation　to　the　variety　of　species。　In　the　former

case；　the　understanding　cogitates　more　under　its　conceptions；　in　the

latter　it　cogitates　more　in　them。　This　distinction　manifests　itself

likewise　in　the　habits　of　thought　peculiar　to　natural　philosophers；

some　of　whom…　the　remarkably　speculative　heads…　may　be　said　to　be

hostile　to　heterogeneity　in　phenomena；　and　have　their　eyes　always

fixed　on　the　unity　of　genera；　while　others…　with　a　strong　empirical

tendency…　aim　unceasingly　at　the　analysis　of　phenomena；　and　almost

destroy　in　us　the　hope　of　ever　being　able　to　estimate　the　character　of

these　according　to　general　principles。

　　The　latter　mode　of　thought　is　evidently　based　upon　a　logical

principle；　the　aim　of　which　is　the　systematic　completeness　of　all

cognitions。　This　principle　authorizes　me；　beginning　at　the　genus；　to

descend　to　the　various　and　diverse　contained　under　it；　and　in　this　way

extension；　as　in　the　former　case　unity；　is　assured　to　the　system。

For　if　we　merely　examine　the　sphere　of　the　conception　which

indicates　a　genus；　we　cannot　discover　how　far　it　is　possible　to

proceed　in　the　division　of　that　sphere；　just　as　it　is　impossible；　from

the　consideration　of　the　space　occupied　by　matter；　to　determine　how

far　we　can　proceed　in　the　division　of　it。　Hence　every　genus　must

contain　different　species；　and　these　again　different　subspecies；　and

as　each　of　the　latter　must　itself　contain　a　sphere　（must　be　of　a

certain　extent；　as　a　conceptus　communis）；　reason　demands　that　no

species　or　sub…species　is　to　be　considered　as　the　lowest　possible。　For

a　species　or　sub…species；　being　always　a　conception；　which　contains

only　what　is　common　to　a　number　of　different　things；　does　not

completely　determine　any　individual　thing；　or　relate　immediately　to

it；　and　must　consequently　contain　other　conceptions；　that　is；　other

sub…species　under　it。　This　law　of　specification　may　be　thus　expressed：

entium　varietates　non　temere　sunt　minuendae。

　　But　it　is　easy　to　see　that　this　logical　law　would　likewise　be

without　sense　or　application；　were　it　not　based　upon　a

transcendental　law　of　specification；　which　certainly　does　not

require　that　the　differences　existing　phenomena　should　be　infinite

in　number；　for　the　logical　principle；　which　merely　maintains　the

indeterminateness　of　the　logical　sphere　of　a　conception；　in　relation

to　its　possible　division；　does　not　authorize　this　statement；　while

it　does　impose　upon　the　understanding　the　duty　of　searching　for

subspecies　to　every　species；　and　minor　differences　in　every

difference。　For；　were　there　no　lower　conceptions；　neither　could

there　be　any　higher。　Now　the　understanding　cognizes　only　by　means　of

conceptions；　consequently；　how　far　soever　it　may　proceed　in

division；　never　by　mere　intuition；　but　always　by　lower　and　lower

conceptions。　The　cognition　of　phenomena　in　their　complete

determination　（which　is　possible　only　by　means　of　the　understanding）

requires　an　unceasingly　continued　specification　of　conceptions；　and

a　progression　to　ever　smaller　differences；　of　which　abstraction　bad

been　made　in　the　conception　of　the　species；　and　still　more　in　that

of　the　genus。

　　This　law　of　specification　cannot　be　deduced　from　experience；　it

can　never　present　us　with　a　principle　of　so　universal　an

application。　Empirical　specification　very　soon　stops　in　its

distinction　of　diversities；　and　requires　the　guidance　of　the

transcendental　law；　as　a　principle　of　the　reason…　a　law　which

imposes　on　us　the　necessity　of　never　ceasing　in　our　search　for

differences；　even　although　these　may　not　present　themselves　to　the

senses。　That　absorbent　earths　are　of　different　kinds　could　only　be

discovered　by　obeying　the　anticipatory　law　of　reason；　which　imposes

upon　the　understanding　the　task　of　discovering　the　differences

existing　between　these　earths；　and　supposes　that　nature　is　richer　in

substances　than　our　senses　would　indicate。　The　faculty　of　the

understanding　belongs　to　us　just　as　much　under　the　presupposition　of

differences　in　the　objects　of　nature；　as　under　the　condition　that

these　objects　are　homogeneous；　because　we　could　not　possess

conceptions；　nor　make　any　use　of　our　understanding；　were　not　the

phenomena　included　under　these　conceptions　in　some　respects

dissimilar；　as　well　as　similar；　in　their　character。

　　Reason　thus　prepares　the　sphere　of　the　understanding　for　the

operations　of　this　faculty：　1。　By　the　principle　of　the　homogeneity

of　the　diverse　in　higher　genera；　2。　By　the　principle　of　the　variety　of

the　homogeneous　in　lower　species；　and；　to　complete　the　systematic

unity；　it　adds；　3。　A　law　of　the　affinity　of　all　conceptions　which

prescribes　a　continuous　transition　from　one　species　to　every　other

by　the　gradual　increase　of　diversity。　We　may　term　these　the　principles

of　the　homogeneity；　the　specification；　and　the　continuity　of　forms。

The　latter　results　from　the　union　of　the　two　former；　inasmuch　as　we

regard　the　systematic　connection　as　complete　in　thought；　in　the　ascent

to　higher　genera；　as　well　as　in　the　descent　to　lower　species。　For

all　diversities　must　be　related　to　each　other；　as　they　all　spring　from

one　highest　genus；　descending　through　the　different　gradations　of　a

more　and　more　extended　determination。

　　We　may　illustrate　the　systematic　unity　produced　by　the　three　logical

principles　in　the　following　manner。　Every　conception　may　be　regarded

as　a　point；　which；　as　the　standpoint　of　a　spectator；　has　a　certain

horizon；　which　may　be　said　to　enclose　a　number　of　things　that　may　be

viewed；　so　to　speak；　from　that　centre。　Within　this　horizon　there

must　be　an　infinite　number　of　other　points；　each　of　which　has　its

own　horizon；　smaller　and　more　circumscribed；　in　other　words；　every

species　contains　sub…species；　according　to　the　principle　of

specification；　and　the　logical　horizon　consists　of　smaller　horizons

（subspecies）；　but　not　of　points　（individuals）；　which　possess　no

extent。　But　different　horizons　or　genera；　which　include　under　them

so　many　conceptions；　may　have　one　common　horizon；　from　which；　as

from　a　mid…point；　they　may　be　surveyed；　and　we　may　proceed　thus；

till　we　arrive　at　the　highest　genus；　or　universal　and　true　horizon；

which　is　determined　by　the　highest　conception；　and　which　contains

under　itself　all　differences　and　varieties；　as　genera；　species；　and

subspecies。

　　To　this　highest　standpoint　I　am　conducted　by　the　law　of　homogeneity；

as　to　all　lower　and　more　variously…determined　conceptions　by　the　law

of　specification。　Now　as　in　this　way　there　exists　no　void　in　the　whole

extent　of　all　possible　conceptions；　and　as　out　of　the　sphere　of

these　the　mind　can　discover　nothing；　there　arises　from　the

presupposition　of　the　universal　horizon　above　mentioned；　and　its

complete　division；　the　principle：　Non　datur　vacuum　formarum。　This

principle　asserts　that　there　are　not　different　primitive　and　highest

g