evolution and ethics and other essays-第3章

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vastly　longer　period　had　elapsed；　throughout　which　it　is　easy　to
follow　the　traces　of　the　same　process　of　ceaseless　modification　and　of
the　internecine　struggle　for　existence　of　living　things；　and　that　even
when　we　can　get　no　further　＇4＇　back；　it　is　not　because　there　is　any
reason　to　think　we　have　reached　the　beginning；　but　because　the　trail
of　the　most　ancient　life　remains　hidden；　or　has　become　obliterated。

Thus　that　state　of　nature　of　the　world　of　plants　which　we　began　by
considering；　is　far　from　possessing　the　attribute　of　permanence。　Rather
its　very　essence　is　impermanence。　It　may　have　lasted　twenty　or　thirty
thousand　years；　it　may　last　for　twenty　or　thirty　thousand　years　more；
without　obvious　change；　but；　as　surely　as　it　has　followed　upon　a　very
different　state；　so　it　will　be　followed　by　an　equally　different
condition。　That　which　endures　is　not　one　or　another　association　of
living　forms；　but　the　process　of　which　the　cosmos　is　the　product；　and
of　which　these　are　among　the　transitory　expressions。　And　in　the　living
world；　one　of　the　most　characteristic　features　of　this　cosmic　process
is　the　struggle　for　existence；　the　competition　of　each　with　all；　the
result　of　which　is　the　selection；　that　is　to　say；　the　survival　of
those　forms　which；　on　the　whole；　are　best　adapted；　to　the　conditions
which　at　any　period　obtain；　and　which　are；　therefore；　in　that　respect；
and　only　in　that　respect；　the　fittest。*　The　acme　reached　by　the　cosmic
＇5＇　process　in　the　vegetation　of　the　downs　is　seen　in　the　turf；　with
its　weeds　and　gorse。　Under　the　conditions；　they　have　come　out　of　the
struggle　victorious；　and；　by　surviving；　have　proved　that　they　are　the
fittest　to　survive。

　　　　*　That　every　theory　of　evolution　must　be　consistent　not　merely
　　　　with　progressive　development；　but　with　indefinite　persistence
　　　　in　the　same　condition　and　with　retrogressive　modification；　is　a
　　　　point　which　I　have　insisted　upon　repeatedly　from　the　year　1862
　　　　till　now。　See　Collected　Essays；　vol。　ii。　pp。　461…89；　vol。　iii。
　　　　p。　33；　vol。　viii。　p。　304。　In　the　address　on　〃Geological
　　　　Contemporaneity　and　Persistent　Types〃　（1862）；　the
　　　　paleontological　proofs　of　this　proposition　were；　I　believe；
　　　　first　set　forth。

That　the　state　of　nature；　at　any　time；　is　a　temporary　phase　of　a
process　of　incessant　change；　which　has　been　going　on　for　innumerable
ages；　appears　to　me　to　be　a　proposition　as　well　established　as　any　in
modern　history。

Paleontology　assures　us；　in　addition；　that　the　ancient　philosophers
who；　with　less　reason；　held　the　same　doctrine；　erred　in　supposing　that
the　phases　formed　a　cycle；　exactly　repeating　the　past；　exactly
foreshadowing　the　future；　in　their　rotations。　On　the　contrary；　it
furnishes　us　with　conclusive　reasons　for　thinking　that；　if　every　link
in　the　ancestry　of　these　humble　indigenous　plants　had　been　preserved
and　were　accessible　to　us；　the　whole　would　present　a　converging　series
of　forms　of　gradually　diminishing　complexity；　until；　at　some　period　in
the　history　of　the　earth；　far　more　remote　than　any　of　which　organic
remains　have　yet　been　discovered；　they　would　merge　in　those　low　groups
among　which　the　Boundaries　between　animal　and　vegetable　life　become
effaced。*

　　　　*　〃On　the　Border　Territory　between　the　Animal　and　the　Vegetable
　　　　Kingdoms；〃　Essays；　vol。　viii。　p。　162

＇6＇　The　word　〃evolution；〃　now　generally　applied　to　the　cosmic　process；
has　had　a　singular　history；　and　is　used　in　various　senses。*　Taken　in
its　popular　signification　it　means　progressive　development；　that　is；
gradual　change　from　a　condition　of　relative　uniformity　to　one　of
relative　complexity；　but　its　connotation　has　been　widened　to　include
the　phenomena　of　retrogressive　metamorphosis；　that　is；　of　progress
from　a　condition　of　relative　complexity　to　one　of　relative　uniformity。

As　a　natural　process；　of　the　same　character　as　the　development　of　a
tree　from　its　seed；　or　of　a　fowl　from　its　egg；　evolution　excludes
creation　and　all　other　kinds　of　supernatural　intervention。　As　the
expression　of　a　fixed　order；　every　stage　of　which　is　the　effect　of
causes　operating　according　to　definite　rules；　the　conception　of
evolution　no　less　excludes　that　of　chance。　　It　is　very　desirable　to
remember　that　evolution　is　not　an　explanation　of　the　cosmic　process；
but　merely　a　generalized　statement　of　the　method　and　results　of　that
process。　And；　further；　that；　if　there　is　proof　that　the　cosmic　process
was　set　going　by　any　agent；　then　that　agent　will　be；　the　creator　of　it
and　of　all　its　products；　although　supernatural　intervention　may　remain
strictly　excluded　from　its　further　course。

So　far　as　that　limited　revelation　of　the　nature　of　things；　which　we
call　scientific　knowledge；　has　＇7＇　yet　gone；　it　tends；　with　constantly
increasing　emphasis；　to　the　belief　that；　not　merely　the　world　of
plants；　but　that　of　animals；　not　merely　living　things；　but　the　whole
fabric　of　the　earth；　not　merely　our　planet；　but　the　whole　solar
system；　not　merely　our　star　and　its　satellites；　but　the　millions　of
similar　bodies　which　bear　witness　to　the　order　which　pervades
boundless　space；　and　has　endured　through　boundless　time；　are　all
working　out　their　predestined　courses　of　evolution。

　　　　*　See　〃Evolution　in　Biology；〃　Essays；　vol。　ii。　p。　187

With　none　of　these　have　I　anything　to　do；　at　present；　except　with　that
exhibited　by　the　forms　of　life　which　tenant　the　earth。　All　plants　and
animals　exhibit　the　tendency　to　vary；　the　causes　of　which　have　yet　to
be　ascertained；　it　is　the　tendency　of　the　conditions　of　life；　at　any
given　time；　while　favouring　the　existence　of　the　variations　best
adapted　to　them；　to　oppose　that　of　the　rest　and　thus　to　exercise
selection；　and　all　living　things　tend　to　multiply　without　limit；　while
the　means　of　support　are　limited；　the　obvious　cause　of　which　is　the
production　of　offspring　more　numerous　than　their　progenitors；　but　with
equal　expectation　of　life　in　the　actuarial　sense。　Without　the　first
tendency　there　could　be　no　evolution。　　Without　the　second；　there　would
be　no　good　reason　why　one　variation　should　disappear　and　another　take
its　place；　that　is　to　say　there　would　be　no　selection。　Without　the　＇8＇
third；　the　struggle　for　existence；　the　agent　of　the　selective　process
in　the　state　of　nature；　would　vanish。*

　　　　*　Collected　Essays；　vol。　ii。　passim。

Granting　the　existence　of　these　tendencies；　all　the　known　facts　of　the
history　of　plants　and　of　animals　may　be　brought　into　rational
correlation。　　And　this　is　more　than　can　be　said　for　any　other
hypothesis　that　I　know　of。　　Such　hypotheses；　for　example；　as　that　of
the　existence　of　a　primitive；　orderless　chaos；　of　a　passive　and
sluggish　eternal　matter　moulded；　with　but　partial　success；　by
archetypal　ideas；　of　a　brand…new　world…stuff　suddenly　created　and
swiftly　shaped　by　a　supernatural　power；　receive　no　encouragement；　but
the　contrary；　from　our　present　knowledge。　That　our　earth　may　once　have
formed　part　of　a　nebulous　cosmic　magma　is　certainly　possible；　indeed
seems　highly　probable；　but　there　is　no　reason　to　doubt　that　order
reigned　there；　as　completely　as　amidst　what　we　regard　as　the　most
finished　works　of　nature　or　of　man。**　The　faith　which　is　born　of
knowledge；　finds　its　object　in　an　eternal　order；　bringing　forth
ceaseless　change；　through　endless　time；　in　endless　space；　the
manifestations　of　the　cosmic　energy　alternating　between　phases　of
potentiality　and　phases　of　explication。　It　may　be　that；　as　Kant
suggests；***　every　cosmic　＇9＇　magma　predestined　to　evolve　into　a　new
world；　has　been　the　no　less　predestined　end　of　a　vanished　predecessor。

　　　　**Ibid。；　vol。　iv。　p。　138；　vol。　v。　pp。　71…73。
　　　　***Ibid。；　vol。　viii。　p。　321。


　　　　　　　　　　　　　　　　　　　　II。

Three　or　four　years　have　elapsed　since　the　state　of　nature；　to　which　I
have　referred；　was　brought　to　an　end；　so　far　as　a　small　patch　of　the
soil　is　concerned；　by　the　intervention　of　man。　The　patch　was　cut　off
from　the　rest　by　a　wall；　within　the　area　thus　protected；　the　native
vegetation　was；　as　far　as　possible；　extirpated；　while　a　colony　of
strange　plants　was　imported　and　set　down　in　its　place。　In　short；　it
was　made　into　a　garden。　At　the　present　time；　this　artificially　treated
area　presents　a