A History of Science, vol 4 - Henry Smith Williams (epub e ink reader .txt) 📗

before in the

history of science has it happened that a great theory has been

nurtured in its author’s brain through infancy and adolescence to

its full legal majority before being sent out into the world.

 

Thus the fuse that led to the great powder-mine had been lighted.

The explosion itself came more than a year later, in November,

1859, when Darwin, after thirteen months of further effort,

completed the outline of his theory, which was at first begun as

an abstract for the Linnaean Society, but which grew to the size

of an independent volume despite his efforts at condensation, and

which was given that ever-to-be-famous title, The Origin of

Species by Means of Natural Selection, or the Preservation of

Favored Races in the Struggle for Life. And what an explosion it

was! The joint paper of 1858 had made a momentary flare, causing

the hearers, as Hooker said, to “speak of it with bated breath,”

but beyond that it made no sensation. What the result was when

the Origin itself appeared no one of our generation need be told.

The rumble and roar that it made in the intellectual world have

not yet altogether ceased to echo after more than forty years of

reverberation.

NEW CHAMPIONS

To the Origin of Species, then, and to its author, Charles

Darwin, must always be ascribed chief credit for that vast

revolution in the fundamental beliefs of our race which has come

about since 1859, and which made the second half of the century

memorable. But it must not be overlooked that no such sudden

metamorphosis could have been effected had it not been for the

aid of a few notable lieutenants, who rallied to the standards of

the leader immediately after the publication of the Origin.

Darwin had all along felt the utmost confidence in the ultimate

triumph of his ideas. “Our posterity,” he declared, in a letter

to Hooker, “will marvel as much about the current belief [in

special creation] as we do about fossil shells having been

thought to be created as we now see them.” But he fully realized

that for the present success of his theory of transmutation the

championship of a few leaders of science was all-essential. He

felt that if he could make converts of Hooker and Lyell and of

Thomas Henry Huxley at once, all would be well.

 

His success in this regard, as in others, exceeded his

expectations. Hooker was an ardent disciple from reading the

proof-sheets before the book was published; Lyell renounced his

former beliefs and fell into line a 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 mystery—and who

himself had barely escaped independent discovery of that

key—lent 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 champions—with here and there another

of less general renown—was 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 simplicity—which at first sight made it seem neither

new nor important—coupled 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 standpoint 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 species—that 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 victory—take 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

variation—as constantly witnessed, for example, in the

differences between parents and offspring—and 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, there still remains one

great life problem which the doctrine of evolution does not

touch. The origin of species, genera, orders, and classes of

beings through endless transmutations is in a sense explained;

but what of the first term of this long series? Whence came that

primordial organism whose transmuted descendants make up the

existing faunas and floras of the globe?

 

There was a time, soon after the doctrine of evolution gained a

hearing, when the answer to that question seemed to some

scientists of authority to have been given by experiment.

Recurring to a former belief, and repeating some earlier

experiments, the director of the Museum of Natural History at

Rouen, M. F. A. Pouchet, reached the conclusion that organic

beings are spontaneously generated about us constantly, in the

familiar processes of putrefaction, which were known to be due to

the agency of microscopic bacteria. But in 1862 Louis Pasteur

proved that this seeming spontaneous generation is in reality due

to the existence of germs in the air. Notwithstanding the

conclusiveness of these experiments, the claims of Pouchet were

revived in England ten years later by Professor Bastian; but then

the experiments of John Tyndall, fully corroborating the results

of Pasteur, gave a final quietus to the claim of “spontaneous

generation” as hitherto formulated.

 

There for the moment the matter rests. But the end is not