a history of science-4-第35章
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few months later； while Huxley； so soon as he had mastered the central idea of natural selection； marvelled that so simple yet all…potent a thought had escaped him so long； and then rushed eagerly into the fray； wielding the keenest dialectic blade that was drawn during the entire controversy。 Then； too； unexpected recruits were found in Sir John Lubbock and John Tyndall； who carried the war eagerly into their respective territories； while Herbert Spencer； who had advocated a doctrine of transmutation on philosophic grounds some years before Darwin published the key to the mysteryand who himself had barely escaped independent discovery of that keylent his masterful influence to the cause。 In America the famous botanist Asa Gray； who had long been a correspondent of Darwin's but whose advocacy of the new theory had not been anticipated； became an ardent propagandist； while in Germany Ernst Heinrich Haeckel； the youthful but already noted zoologist； took up the fight with equal enthusiasm。
Against these few doughty championswith here and there another of less general renownwas arrayed； at the outset； practically all Christendom。 The interest of the question came home to every person of intelligence； whatever his calling； and the more deeply as it became more and more clear how far…reaching are the real bearings of the doctrine of natural selection。 Soon it was seen that should the doctrine of the survival of the favored races through the struggle for existence win； there must come with it as radical a change in man's estimate of his own position as had come in the day when； through the efforts of Copernicus and Galileo； the world was dethroned from its supposed central position in the universe。 The whole conservative majority of mankind recoiled from this necessity with horror。 And this conservative majority included not laymen merely； but a vast preponderance of the leaders of science also。
With the open…minded minority； on the other hand； the theory of natural selection made its way by leaps and bounds。 Its delightful simplicitywhich at first sight made it seem neither new nor importantcoupled with the marvellous comprehensiveness of its implications； gave it a hold on the imagination； and secured it a hearing where other theories of transmutation of species had been utterly scorned。 Men who had found Lamarck's conception of change through voluntary effort ridiculous； and the vaporings of the Vestiges altogether despicable； men whose scientific cautions held them back from Spencer's deductive argument； took eager hold of that tangible； ever…present principle of natural selection； and were led on and on to its goal。 Hour by hour the attitude of the thinking world towards this new principle changed； never before was so great a revolution wrought so suddenly。
Nor was this merely because 〃the times were ripe〃 or 〃men's minds prepared for evolution。〃 Darwin himself bears witness that this was not altogether so。 All through the years in which he brooded this theory he sounded his scientific friends； and could find among them not one who acknowledged a doctrine of transmutation。 The reaction from the stand…point of Lamarck and Erasmus Darwin and Goethe had been complete； and when Charles Darwin avowed his own conviction he expected always to have it met with ridicule or contempt。 In 1857 there was but one man speaking with any large degree of authority in the world who openly avowed a belief in transmutation of speciesthat man being Herbert Spencer。 But the Origin of Species came； as Huxley has said； like a flash in the darkness； enabling the benighted voyager to see the way。 The score of years during which its author had waited and worked had been years well spent。 Darwin had become； as he himself says； a veritable Croesus； 〃overwhelmed with his riches in facts〃facts of zoology； of selective artificial breeding； of geographical distribution of animals； of embryology； of paleontology。 He had massed his facts about his theory； condensed them and recondensed； until his volume of five hundred pages was an encyclopaedia in scope。 During those long years of musing he had thought out almost every conceivable objection to his theory； and in his book every such objection was stated with fullest force and candor； together with such reply as the facts at command might dictate。 It was the force of those twenty years of effort of a master…mind that made the sudden breach in the breaswtork｛sic｝ of current thought。
Once this breach was effected the work of conquest went rapidly on。 Day by day squads of the enemy capitulated and struck their arms。 By the time another score of years had passed the doctrine of evolution had become the working hypothesis of the scientific world。 The revolution had been effected。
And from amid the wreckage of opinion and belief stands forth the figure of Charles Darwin； calm； imperturbable； serene； scatheless to ridicule； contumely； abuse； unspoiled by ultimate success； unsullied alike by the strife and the victorytake him for all in all； for character； for intellect； for what he was and what he did； perhaps the most Socratic figure of the century。 When； in 1882； he died； friend and foe alike conceded that one of the greatest sons of men had rested from his labors； and all the world felt it fitting that the remains of Charles Darwin should be entombed in Westminster Abbey close beside the honored grave of Isaac Newton。 Nor were there many who would dispute the justice of Huxley's estimate of his accomplishment： 〃He found a great truth trodden under foot。 Reviled by bigots； and ridiculed by all the world； he lived long enough to see it； chiefly by his own efforts； irrefragably established in science； inseparably incorporated with the common thoughts of men； and only hated and feared by those who would revile but dare not。〃
THE ORIGIN OF THE FITTEST
Wide as are the implications of the great truth which Darwin and his co…workers established； however； it leaves quite untouched the problem of the origin of those 〃favored variations〃 upon which it operates。 That such variations are due to fixed and determinate causes no one understood better than Darwin； but in his original exposition of his doctrine he made no assumption as to what these causes are。 He accepted the observed fact of variationas constantly witnessed； for example； in the differences between parents and offspringand went ahead from this assumption。
But as soon as the validity of the principle of natural selection came to be acknowledged speculators began to search for the explanation of those variations which； for purposes of argument； had been provisionally called 〃spontaneous。〃 Herbert Spencer had all along dwelt on this phase of the subject； expounding the Lamarckian conceptions of the direct influence of the environment （an idea which had especially appealed to Buffon and to Geoffroy Saint…Hilaire）； and of effort in response to environment and stimulus as modifying the individual organism； and thus supplying the basis for the operation of natural selection。 Haeckel also became an advocate of this idea； and presently there arose a so…called school of neo…Lamarckians； which developed particular strength and prominence in America under the leadership of Professors A。 Hyatt and E。 D。 Cope。
But just as the tide of opinion was turning strongly in this direction； an utterly unexpected obstacle appeared in the form of the theory of Professor August Weismann； put forward in 1883； which antagonized the Lamarckian conception （though not touching the Darwinian； of which Weismann is a firm upholder） by denying that individual variations； however acquired by the mature organism； are transmissible。 The flurry which this denial created has not yet altogether subsided； but subsequent observations seem to show that it was quite disproportionate to the real merits of the case。 Notwithstanding Professor Weismann's objections； the balance of evidence appears to favor the view that the Lamarckian factor of acquired variations stands as the complement of the Darwinian factor of natural selection in effecting the transmutation of species。
Even though this partial explanation of what Professor Cope calls the 〃origin of the fittest〃 be accepted；
