essays on life, art and science-第30章

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manner　indicated　in　Darwin's　hypothesis　of　pangenesis；　is　wholly
unnecessary　for　the　explanation　of　these　phenomena。　　Still　we　cannot
exclude　the　possibility　of　such　a　transmission　occasionally
occurring；　for　even　if　the　greater　part　of　the　effects　must　be
attributable　to　natural　selection；　there　might　be　a　smaller　part　in
certain　cases　which　depends　on　this　exceptional　factor。〃

I　repeatedly　tried　to　understand　Mr。　Darwin's　theory　of　pangenesis；
and　so　often　failed　that　I　long　since　gave　the　matter　up　in　despair。
I　did　so　with　the　less　unwillingness　because　I　saw　that　no　one　else
appeared　to　understand　the　theory；　and　that　even　Mr。　Darwin's
warmest　adherents　regarded　it　with　disfavour。　　If　Mr。　Darwin　means
that　every　cell　of　the　body　throws　off　minute　particles　that　find
their　way　to　the　germ…cells；　and　hence　into　the　new　embryo；　this　is
indeed　difficult　of　comprehension　and　belief。　　If　he　means　that　the
rhythms　or　vibrations　that　go　on　ceaselessly　in　every　cell　of　the
body　communicate　themselves　with　greater　or　less　accuracy　or
perturbation；　as　the　case　may　be；　to　the　cells　that　go　to　form
offspring；　and　that　since　the　characteristics　of　matter　are
determined　by　vibrations；　in　communicating　vibrations　they　in　effect
communicate　matter；　according　to　the　view　put　forward　in　the　last
chapter　of　my　book　〃Luck　or　Cunning；〃　｛36｝　then　we　can　better
understand　it。　　I　have　nothing；　however；　to　do　with　Mr。　Darwin's
theory　of　pangenesis　beyond　avoiding　the　pretence　that　I　understand
either　the　theory　itself　or　what　Professor　Weismann　says　about　it；
all　I　am　concerned　with　is　Professor　Weismann's　admission；　made
immediately　afterwards；　that　the　somatic　cells　may；　and　perhaps
sometimes　do；　impart　characteristics　to　the　germ…cells。

〃A　complete　and　satisfactory　refutation　of　such　an　opinion；〃　he
continues；　〃cannot　be　brought　forward　at　present〃；　so　I　suppose　we
must　wait　a　little　longer；　but　in　the　meantime　we　may　again　remark
that；　if　we　admit　even　occasional　communication　of　changes　in　the
somatic　cells　to　the　germ…cells；　we　have　let　in　the　thin　end　of　the
wedge；　as　Mr。　Darwin　did　when　he　said　that　use　and　disuse　did　a　good
deal　towards　modification。　　Buffon；　in　his　first　volume　on　the　lower
animals；　｛37｝　dwells　on　the　impossibility　of　stopping　the　breach
once　made　by　admission　of　variation　at　all。　　〃If　the　point；〃　he
writes；　〃were　once　gained；　that　among　animals　and　vegetables　there
had　been；　I　do　not　say　several　species；　but　even　a　single　one；　which
had　been　produced　in　the　course　of　direct　descent　from　another
species；　if；　for　example；　it　could　be　once　shown　that　the　ass　was
but　a　degeneration　from　the　horsethen　there　is　no　farther　limit　to
be　set　to　the　power　of　Nature；　and　we　should　not　be　wrong　in
supposing　that　with　sufficient　time　she　could　have　evolved　all　other
organised　forms　from　one　primordial　type。〃　　So　with　use　and　disuse
and　transmission　of　acquired　characteristics　generallyonce　show
that　a　single　structure　or　instinct　is　due　to　habit　in　preceding
generations；　and　we　can　impose　no　limit　on　the　results　achievable　by
accumulation　in　this　respect；　nor　shall　we　be　wrong　in　conceiving　it
as　possible　that　all　specialisation；　whether　of　structure　or
instinct；　may　be　due　ultimately　to　habit。

How　far　this　can　be　shown　to　be　probable　is；　of　course；　another
matter；　but　I　am　not　immediately　concerned　with　this；　all　I　am
concerned　with　now　is　to　show　that　the　germ…cells　not　unfrequently
become　permanently　affected　by　events　that　have　made　a　profound
impression　upon　the　somatic　cells；　in　so　far　that　they　transmit　an
obvious　reminiscence　of　the　impression　to　the　embryos　which　they　go
subsequently　towards　forming。　　This　is　all　that　is　necessary　for　my
case；　and　I　do　not　find　that　Professor　Weismann；　after　all；　disputes
it。

But　here；　again；　comes　the　difficulty　of　saying　what　Professor
Weismann　does；　and　what　he　does　not；　dispute。　　One　moment　he　gives
all　that　is　wanted　for　the　Lamarckian　contention；　the　next　he　denies
common…sense　the　bare　necessaries　of　life。　　For　a　more　exhaustive
and　detailed　criticism　of　Professor　Weismann's　position；　I　would
refer　the　reader　to　an　admirably　clear　article　by　Mr。　Sidney　H。
Vines；　which　appeared　in　Nature；　October　24；　1889。　　I　can　only　say
that　while　reading　Professor　Weismann's　book；　I　feel　as　I　do　when　I
read　those　of　Mr。　Darwin；　and　of　a　good　many　other　writers　on
biology　whom　I　need　not　name。　　I　become　like　a　fly　in　a　window…pane。
I　see　the　sunshine　and　freedom　beyond；　and　buzz　up　and　down　their
pages；　ever　hopeful　to　get　through　them　to　the　fresh　air　without；
but　ever　kept　back　by　a　mysterious　something；　which　I　feel　but
cannot　either　grasp　or　see。　　It　was　not　thus　when　I　read　Buffon；
Erasmus　Darwin；　and　Lamarck；　it　is　not　thus　when　I　read　such
articles　as　Mr。　Vines's　just　referred　to。　　Love　of　self…display；　and
the　want　of　singleness　of　mind　that　it　inevitably　engendersthese；
I　suppose；　are　the　sins　that　glaze　the　casements　of　most　men's
minds；　and　from　these；　no　matter　how　hard　he　tries　to　free　himself；
nor　how　much　he　despises　them；　who　is　altogether　exempt？

Finally；　then；　when　we　consider　the　immense　mass　of　evidence
referred　to　briefly；　but　sufficiently；　by　Mr。　Charles　Darwin；　and
referred　to　without　other；　for　the　most　part；　than　off…hand
dismissal　by　Professor　Weismann　in　the　last　of　the　essays　that　have
been　recently　translated；　I　do　not　see　how　any　one　who　brings　an
unbiased　mind　to　the　question　can　hesitate　as　to　the　side　on　which
the　weight　of　testimony　inclines。　　Professor　Weismann　declares　that
〃the　transmission　of　mutilations　may　be　dismissed　into　the　domain　of
fable。〃　｛38｝　　If　so；　then；　whom　can　we　trust？　　What　is　the　use　of
science　at　all　if　the　conclusions　of　a　man　as　competent　as　I　readily
admit　Mr。　Darwin　to　have　been；　on　the　evidence　laid　before　him　from
countless　sources；　is　to　be　set　aside　lightly　and　without　giving　the
clearest　and　most　cogent　explanation　of　the　why　and　wherefore？　　When
we　see　a　person　〃ostrichising〃　the　evidence　which　he　has　to　meet；　as
clearly　as　I　believe　Professor　Weismann　to　be　doing；　we　shall　in
nine　cases　out　of　ten　be　right　in　supposing　that　he　knows　the
evidence　to　be　too　strong　for　him。



THE　DEADLOCK　IN　DARWINISMPART　III



Now　let　me　return　to　the　recent　division　of　biological　opinion　into
two　main　streamsLamarckism　and　Weismannism　Both　Lamarckians　and
Weismannists；　not　to　mention　mankind　in　general；　admit　that　the
better　adapted　to　its　surroundings　a　living　form　may　be；　the　more
likely　it　is　to　outbreed　its　compeers。　　The　world　at　large；　again；
needs　not　to　be　told　that　the　normal　course　is　not　unfrequently
deflected　through　the　fortunes　of　war；　nevertheless；　according　to
Lamarckians　and　Erasmus…Darwinians；　habitual　effort；　guided　by　ever…
growing　intelligencethat　is　to　say；　by　continued　increase　of　power
in　the　matter　of　knowing　our　likes　and　dislikeshas　been　so　much
the　main　factor　throughout　the　course　of　organic　development；　that
the　rest；　though　not　lost　sight　of；　may　be　allowed　to　go　without
saying。　　According；　on　the　other　hand；　to　extreme　Charles…Darwinians
and　Weismannists；　habit；　effort　and　intelligence　acquired　during　the
experience　of　any　one　life　goes　for　nothing。　　Not　even　a　little
fraction　of　it　endures　to　the　benefit　of　offspring。　　It　dies　with
him　in　whom　it　is　acquired；　and　the　heirs　of　a　man's　body　take　no
interest　therein。　　To　state　this　doctrine　is　to　arouse　instinctive
loathing；　it　is　my　fortunate　task　to　maintain　that　such　a　nightmare
of　waste　and　death　is　as　baseless　as　it　is　repulsive。

The　split　in　biological　opinion　occasioned　by　the　deadlock　to　which
Charles…Darwinism　has　been　reduced；　though　comparatively　recent；
widens　rapidly。　　Ten　years　ago　Lamarck's　name　was　mentioned　only　as
a　byword　for　extravagance；　now；　we　cannot　take　up　a　number　of　Nature
without　seeing　how　hot　the　contention　is　between　his　followers　and
those　of　Weismann。　　This　must　be　referred；　as　I　implied　earlier；　to
growing　perception　that　Mr。　Darwin　should　either　have　gone　farther
towards　Lamarckism　or　not　so　far。　　In　admitting　use　and　disuse　as
freely　as　he　did；　he　gave　Lamarckians　leverage　for　the　overthrow　of
a　system　based　ostensibly　on　the　accumulation　of　fortunate
accidents。　　In　assigning　the　lion's　share　of　development　to　the
accumulation　of　fortunate　accidents；　he　tempted　fortuitists　to　try
to　cut　the　ground　from　under　Lamarck's　feet　by　denying　that　the
effects　of　use　and　disuse　can　be　inherited　at　all。　　When　the　public
had　once　got　to　understand　what　Lamarck　had　intended；　and　wherein
Mr。　Charles　Darwin　had　differed　from　him；　it　became　impossible　for
Charles…Darwinians　to　remain　where　they　were；　nor　is　it　easy　to　see
what　course　was　open　to　them　except　to　cast　about　for　a　theory　by
which　they　could　get　rid　of　use　and　disuse　altogether。　　Weismannism；
therefore；　is　the　inevitable　outcome　of　the　straits　to　which
Charles…Darwinians　were　reduced　through　the　way　in　which　their
leader　had　halted　between　two　opinions。

This　is　why　Charles…Darwinians；　from　Professor　Huxley　downwards；
have　kept　the　difference　between　Lamarck's　opinions　and　those　of　Mr。
Darwin　so　much　in　the　background。　　Unwillingness　to　make　this
understood　is　nowhere　manifested　more　clearly　than　in　Dr。　Francis
Darwin's　life　of　his　father。　　In　this　work　Lamarck　is　sneered　at
once　or　twice；　and　told　to　go　away；　but　there　is　no　attempt　to　state
the　two　cases　side　by　side；　from　which；　as　from　not　a　little　else；　I
conclude　that　Dr。　Francis　Darwin　has　descended　from　his　father　with
singularly　little　modification。

Proceeding　to　the　evidence　for　the　transmissions　of　acquired　habits；
I　will　quote　two　recently　adduced　examples　from　among　the　many　that
have　been　credibly　attested。　　The　first　was　contributed　to　Nature
（March　14；　1889）　by　Professor　Marcus　M。　Hartog；　who　wrote：…

〃A。　B。　is　moderately　myopic　and　very　astigmatic　in　the　left　eye；
extremely　myopic　in　the　right。　　As　the　left　eye　gave　such　bad　images
for　near　objects；　he　was　compelled　in　childhood　to　mask　it；　and
acquired　the　habit　of　leaning　his　head　on　his　left　arm　for　writing；
so　as　to　blind　that　eye；　or　of　resting　the　left　temple　and　eye　on
the　hand；　with　the　elbow　on　the　table。　　At　the　age　of　fifteen　the
eyes　were　equalised　by　the　use　of　suitable　spectacles；　and　he　soon
lost　the　habit　completely　and　permanently。　　He　is　now　the　father　of
two　children；　a　boy　and　a　girl；　whose　vision　（tested　repeatedly　and
fully）　is　emmetropic　in　both　eyes；　so　that　they　have　not　inherited
the　congenital　optical　defect　of　their　father。　　All　the　same；　they
have　both　of　them　inherited　his　early　acquired　habit；　and　need
constant　watchfulness　to　prevent　their　hiding　the　left　eye　when
writing；　by　resting　the　head　on　the　left　forearm　or　hand。　　Imitation
is　here　quite　out　of　the　question。

〃Considering　that　every　habit　involves　changes　in　the　proportional
development　of　the　muscular　and　osseous　systems；　and　hence　probably
of　the　nervous　system　also；　the　importance　of　inherited　habits；
natural　or　acquired；　cannot　be　overlooked　in　the　general　theory　of
inheritance。　　I　am　fully　aware　that　I　shall　be　accused　of　flat
Lamarckism；　but　a　nickname　is　not　an　argument。〃

To　this　Professor　Ray　Lankest