strongest supporters of the special creation hypothesis had not, now and
then, an uneasy consciousness that all was not right, their position
seemed more impregnable than ever, if not by its own inherent strength,
at any rate by the obvious failure of all the attempts which had been
made to carry it. On the other hand, however much the few, who thought
deeply on the question of species, might be repelled by the generally
received dogmas, they saw no way of escaping from them, save by the
adoption of suppositions, so little justified by experiment or by
observation, as to be at least equally distasteful.
The choice lay between two absurdities and a middle condition of uneasy
scepticism; which last, however unpleasant and unsatisfactory, was
obviously the only justifiable state of mind under the circumstances.
Such being the general ferment in the minds of naturalists, it is no
wonder that they mustered strong in the rooms of the Linnæan Society, on
the 1st of July of the year 1858, to hear two papers by authors living
on opposite sides of the globe, working out their results independently,
and yet professing to have discovered one and the same solution of all
the problems connected with species. The one of these authors was an
able naturalist, Mr. Wallace, who had been employed for some years in
studying the productions of the islands of the Indian Archipelago, and
who had forwarded a memoir embodying his views to Mr. Darwin, for
communication to the Linnæan Society. On perusing the essay, Mr. Darwin
was not a little surprised to find that it embodied some of the leading
ideas of a great work which he had been preparing for twenty years, and
parts of which, containing a development of the very same views, had
been perused by his private friends fifteen or sixteen years before.
Perplexed in what manner to do full justice both to his friend and to
himself, Mr. Darwin placed the matter in the hands of Dr. Hooker and Sir
Charles Lyell, by whose advice he communicated a brief abstract of his
own views to the Linnæan Society, at the same time that Mr. Wallace's
paper was read. Of that abstract, the work on the "Origin of Species" is
an enlargement; but a complete statement of Mr. Darwin's doctrine is
looked for in the large and well-illustrated work which he is said to be
preparing for publication.
The Darwinian hypothesis has the merit of being eminently simple and
comprehensible in principle, and its essential positions may be stated
in a very few words: all species have been produced by the development
of varieties from common stocks by the conversion of these first into
permanent races and then into new species, by the process of _natural
selection_, which process is essentially identical with that artificial
selection by which man has originated the races of domestic animals--the
_struggle for existence_ taking the place of man, and exerting, in the
case of natural selection, that selective action which he performs in
artificial selection.
The evidence brought forward by Mr. Darwin in support of his hypothesis
is of three kinds. First, he endeavours to prove that species may be
originated by selection; secondly, he attempts to show that natural
causes are competent to exert selection; and thirdly, he tries to prove
that the most remarkable and apparently anomalous phænomena exhibited by
the distribution, development, and mutual relations of species, can be
shown to be deducible from the general doctrine of their origin, which
he propounds, combined with the known facts of geological change; and
that, even if all these phænomena are not at present explicable by it,
none are necessarily inconsistent with it.
There cannot be a doubt that the method of inquiry which Mr. Darwin has
adopted is not only rigorously in accordance with the canons of
scientific logic, but that it is the only adequate method. Critics
exclusively trained in classics or in mathematics, who have never
determined a scientific fact in their lives by induction from experiment
or observation, prate learnedly about Mr. Darwin's method, which is not
inductive enough, not Baconian enough, forsooth, for them. But even if
practical acquaintance with the process of scientific investigation is
denied them, they may learn, by the perusal of Mr. Mill's admirable
chapter "On the Deductive Method," that there are multitudes of
scientific inquiries, in which the method of pure induction helps the
investigator but a very little way.
"The mode of investigation," says Mr. Mill, "which, from the proved
inapplicability of direct methods of observation and experiment,
remains to us as the main source of the knowledge we possess, or
can acquire, respecting the conditions and laws of recurrence of
the more complex phænomena, is called, in its most general
expression, the deductive method, and consists of three operations:
the first, one of direct induction; the second, of ratiocination;
and the third, of verification."
Now, the conditions which have determined the existence of species are
not only exceedingly complex, but, so far as the great majority of them
are concerned, are necessarily beyond our cognizance. But what Mr.
Darwin has attempted to do is in exact accordance with the rule laid
down by Mr. Mill; he has endeavoured to determine certain great facts
inductively, by observation and experiment; he has then reasoned from
the data thus furnished; and lastly, he has tested the validity of his
ratiocination by comparing his deductions with the observed facts of
Nature. Inductively, Mr. Darwin endeavours to prove that species arise
in a given way. Deductively, he desires to show that, if they arise in
that way, the facts of distribution, development, classification, &c.,
may be accounted for, _i.e._ may be deduced from their mode of origin,
combined with admitted changes in physical geography and climate, during
an indefinite period. And this explanation, or coincidence of observed
with deduced facts, is, so far as it extends, a verification of the
Darwinian view.
There is no fault to be found with Mr. Darwin's method, then; but it is
another question whether he has fulfilled all the conditions imposed by
that method. Is it satisfactorily proved, in fact, that species may be
originated by selection? that there is such a thing as natural
selection? that none of the phænomena exhibited by species are
inconsistent with the origin of species in this way? If these questions
can be answered in the affirmative, Mr. Darwin's view steps out of the
ranks of hypotheses into those of proved theories; but, so long as the
evidence at present adduced falls short of enforcing that affirmation,
so long, to our minds, must the new doctrine be content to remain among
the former--an extremely valuable, and in the highest degree probable,
doctrine, indeed the only extant hypothesis which is worth anything in a
scientific point of view; but still a hypothesis, and not yet the theory
of species.
After much consideration, and with assuredly no bias against Mr.
Darwin's views, it is our clear conviction that, as the evidence stands,
it is not absolutely proven that a group of animals, having all the
characters exhibited by species in Nature, has ever been originated by
selection, whether artificial or natural. Groups having the
morphological character of species, distinct and permanent races in
fact, have been so produced over and over again; but there is no
positive evidence, at present, that any group of animals has, by
variation and selective breeding, given rise to another group which was
even in the least degree infertile with the first. Mr. Darwin is
perfectly aware of this weak point, and brings forward a multitude of
ingenious and important arguments to diminish the force of the
objection. We admit the value of these arguments to their fullest
extent; nay, we will go so far as to express our belief that
experiments, conducted by a skilful physiologist, would very probably
obtain the desired production of mutually more or less infertile breeds
from a common stock, in a comparatively few years; but still, as the
case stands at present, this "little rift within the lute" is not to be
disguised nor overlooked.
In the remainder of Mr. Darwin's argument our own private ingenuity has
not hitherto enabled us to pick holes of any great importance; and
judging by what we hear and read, other adventurers in the same field do
not seem to have been much more fortunate. It has been urged, for
instance, that in his chapters on the struggle for existence and on
natural selection, Mr. Darwin does not so much prove that natural
selection does occur, as that it must occur; but, in fact, no other sort
of demonstration is attainable. A race does not attract our attention in
Nature until it has, in all probability, existed for a considerable
time, and then it is too late to inquire into the conditions of its
origin. Again, it is said that there is no real analogy between the
selection which takes place under domestication, by human influence, and
any operation which can be effected by Nature, for man interferes
intelligently. Reduced to its elements, this argument implies that an
effect produced with trouble by an intelligent agent must, _à fortiori_,
be more troublesome, if not impossible, to an unintelligent agent. Even
putting aside the question whether Nature, acting as she does according
to definite and invariable laws, can be rightly called an unintelligent
agent, such a position as this is wholly untenable. Mix salt and sand,
and it shall puzzle the wisest of men, with his mere natural appliances,
to separate all the grains of sand from all the grains of salt; but a
shower of rain will effect the same object in ten minutes. And so, while
man may find it tax all his intelligence to separate any variety which
arises, and to breed selectively from it, the destructive agencies
incessantly at work in Nature, if they find one variety to be more
soluble in circumstances than the other, will inevitably, in the long
run, eliminate it.
A frequent and a just objection to the Lamarckian hypothesis of the
transmutation of species is based upon the absence of transitional forms
between many species. But against the Darwinian hypothesis this argument
has no force. Indeed, one of the most valuable and suggestive parts of
Mr. Darwin's work is that in which he proves, that the frequent absence
of transitions is a necessary consequence of his doctrine, and that the
stock whence two or more species have sprung, need in no respect be
intermediate between these species. If any two species have arisen from
a common stock in the same way as the carrier and the pouter, say, have
arisen from the rock-pigeon, then the common stock of these two species
need be no more intermediate between the two than the rock-pigeon is
between the carrier and pouter. Clearly appreciate the force of this
analogy, and all the arguments against the origin of species by
selection, based on the absence of transitional forms, fall to the
ground. And Mr. Darwin's position might, we think, have been even
stronger than it is if he had not embarrassed himself with the aphorism,
"_Natura non facit saltum_," which turns up so often in his pages. We
believe, as we have said above, that Nature does make jumps now and
then, and a recognition of the fact is of no small importance in
disposing of many minor objections to the doctrine of transmutation.
But we must pause. The discussion of Mr. Darwin's arguments in detail
would lead us far beyond the limits within which we proposed, at
starting, to confine this article. Our object has been attained if we
have given an intelligible, however brief, account of the established
facts connected with species, and of the relation of the explanation of
those facts offered by Mr. Darwin to the theoretical views held by his
predecessors and his contemporaries, and, above all, to the requirements
of scientific logic. We have ventured to point out that it does not, as
yet, satisfy all those requirements; but we do not hesitate to assert
that it is as superior to any preceding or contemporary hypothesis, in
the extent of observational and experimental basis on which it rests, in
its rigorously scientific method, and in its power of explaining
biological phænomena, as was the hypothesis of Copernicus to the
speculations of Ptolemy. But the planetary orbits turned out to be not
quite circular after all, and, grand as was the service Copernicus
rendered to science, Kepler and Newton had to come after him. What if
the orbit of Darwinism should be a little too circular? What if species
should offer residual phænomena, here and there, not explicable by
natural selection? Twenty years hence naturalists may be in a position
to say whether this is, or is not, the case; but in either event they
will owe the author of "The Origin of Species" an immense debt of
gratitude. We should leave a very wrong impression on the reader's mind
if we permitted him to suppose that the value of that work depends
wholly on the ultimate justification of the theoretical views which it
contains. On the contrary, if they were disproved to-morrow, the book
would still be the best of its kind--the most compendious statement of
well-sifted facts bearing on the doctrine of species that has ever
appeared. The chapters on Variation, on the Struggle for Existence, on
Instinct, on Hybridism, on the Imperfection of the Geological Record, on
Geographical Distribution, have not only no equals, but, so far as our
knowledge goes, no competitors, within the range of biological
literature. And viewed as a whole, we do not believe that, since the
publication of Von Baer's Researches on Development, thirty years ago,
any work has appeared calculated to exert so large an influence, not
only on the future of Biology, but in extending the domination of
Science over regions of thought into which she has, as yet, hardly
penetrated.
FOOTNOTES:
[61] On the Osteology of the Chimpanzees and Orangs: Transactions of the
Zoological Society, 1858.
[62] Colonel Humphreys' statements are exceedingly explicit on this
point:--"When an Ancon ewe is impregnated by a common ram, the increase
resembles wholly either the ewe or the ram. The increase of the common
ewe impregnated by an Ancon ram follows entirely the one or the other,
without blending any of the distinguishing and essential peculiarities
of both. Frequent instances have happened where common ewes have had
twins by Ancon rams, when one exhibited the complete marks and features
of the ewe, the other of the ram. The contrast has been rendered
singularly striking, when one short-legged and one long-legged lamb,
produced at a birth, have been seen sucking the dam at the same
time."--_Philosophical Transactions_, 1813, Pt. I., pp. 89, 90.
[63] Recent investigations tend to show that this statement is not
strictly accurate.--1870.
[64] See Phil. Zoologique, vol. i. p. 222, et seq.
XIII.
CRITICISMS ON "THE ORIGIN OF SPECIES."
1. UEBER DIE DARWIN'SCHE SCHÖPFUNGSTHEORIE; EIN VORTAG, VON A.
KÖLLIKER. Leipzig, 1864.
2. EXAMINATION DU LIVRE DE M. DARWIN SUR L'ORIGINE DES ESPÈCES.
PAR P. FLOURENS. Paris, 1864.
In the course of the present year [1864] several foreign commentaries
upon Mr. Darwin's great work have made their appearance. Those who have
perused that remarkable chapter of the "Antiquity of Man," in which Sir
Charles Lyell draws a parallel between the development of species and
that of languages, will be glad to hear that one of the most eminent
philologers of Germany, Professor Schleicher, has, independently,
published a most instructive and philosophical pamphlet (an excellent
notice of which is to be found in the _Reader_, for February 27th of
this year) supporting similar views with all the weight of his special
knowledge and established authority as a linguist. Professor Haeckel, to
whom Schleicher addresses himself, previously took occasion, in his
splendid monograph on the _Radiolaria_,[65] to express his high
appreciation of, and general concordance with, Mr. Darwin's views.
But the most elaborate criticisms of the "Origin of Species" which have
appeared are two works of very widely different merit, the one by
Professor Kölliker, the well-known anatomist and histologist of
Würzburg; the other by M. Flourens, Perpetual Secretary of the French
Academy of Sciences.
Professor Kölliker's critical essay "Upon the Darwinian Theory" is, like
all that proceeds from the pen of that thoughtful and accomplished
writer, worthy of the most careful consideration. It comprises a brief
but clear sketch of Darwin's views, followed by an enumeration of the
leading difficulties in the way of their acceptance; difficulties which
would appear to be insurmountable to Professor Kölliker, inasmuch as he
proposes to replace Mr. Darwin's Theory by one which he terms the
"Theory of Heterogeneous Generation." We shall proceed to consider first
the destructive, and secondly, the constructive portion of the essay.
We regret to find ourselves compelled to dissent very widely from many
of Professor Kölliker's remarks; and from none more thoroughly than from
those in which he seeks to define what we may term the philosophical
position of Darwinism.
"Darwin," says Professor Kölliker, "is, in the fullest sense of the
Word, a Teleologist. He says quite distinctly (First Edition, pp.
199, 200) that every particular in the structure of an animal has
been created for its benefit, and he regards the whole series of
animal forms only from this point of view."
And again:
"7. The teleological general conception adopted by Darwin is a
mistaken one.
"Varieties arise irrespectively of the notion of purpose, or of
utility, according to general laws of Nature, and may be either
useful, or hurtful, or indifferent.
"The assumption that an organism exists only on account of some
definite end in view, and represents something more than the
incorporation of a general idea, or law, implies a one-sided
conception of the universe. Assuredly, every organ has, and every
organism fulfils, its end, but its purpose is not the condition of
its existence. Every organism is also sufficiently perfect for the
purpose it serves, and in that, at least, it is useless to seek for
a cause of its improvement."
It is singular how differently one and the same book will impress
different minds. That which struck the present writer most forcibly on
his first perusal of the "Origin of Species" was the conviction that
Teleology, as commonly understood, had received its deathblow at Mr.
Darwin's hands. For the teleological argument runs thus: an organ or
organism (A) is precisely fitted to perform a function or purpose (B);
therefore it was specially constructed to perform that function. In
Paley's famous illustration, the adaptation of all the parts of the
watch to the function, or purpose, of showing the time, is held to be
evidence that the watch was specially contrived to that end; on the
ground, that the only cause we know of, competent to produce such an
effect as a watch which shall keep time, is a contriving intelligence
adapting the means directly to that end.
Suppose, however, that any one had been able to show that the watch had
not been made directly by any person, but that it was the result of the
modification of another watch which kept time but poorly; and that this
again had proceeded from a structure which could hardly be called a
watch at all--seeing that it had no figures on the dial and the hands
were rudimentary; and that going back and back in time we came at last
to a revolving barrel as the earliest traceable rudiment of the whole
fabric. And imagine that it had been possible to show that all these
changes had resulted, first, from a tendency of the structure to vary
indefinitely; and secondly, from something in the surrounding world
which helped all variations in the direction of an accurate time-keeper,
and checked all those in other directions; then it is obvious that the
force of Paley's argument would be gone. For it would be demonstrated
that an apparatus thoroughly well adapted to a particular purpose might
be the result of a method of trial and error worked by unintelligent
agents, as well as of the direct application of the means appropriate to
that end, by an intelligent agent.
Now it appears to us that what we have here, for illustration's sake,
supposed to be done with the watch, is exactly what the establishment of
Darwin's Theory will do for the organic world. For the notion that every
organism has been created as it is and launched straight at a purpose,
Mr. Darwin substitutes the conception of something which may fairly be
termed a method of trial and error. Organisms vary incessantly; of these
variations the few meet with surrounding conditions which suit them and
thrive; the many are unsuited and become extinguished.
According to Teleology, each organism is like a rifle bullet fired
straight at a mark; according to Darwin, organisms are like grapeshot of
which one hits something and the rest fall wide.
For the teleologist an organism exists because it was made for the
conditions in which it is found; for the Darwinian an organism exists
because, out of many of its kind, it is the only one which has been
able to persist in the conditions in which it is found.
Teleology implies that the organs of every organism are perfect and
cannot be improved; the Darwinian theory simply affirms that they work
well enough to enable the organism to hold its own against such
competitors as it has met with, but admits the possibility of indefinite
improvement. But an example may bring into clearer light the profound
opposition between the ordinary teleological, and the Darwinian,
conception.
Cats catch mice, small birds and the like, very well. Teleology tells us
that they do so because they were expressly constructed for so
doing--that they are perfect mousing apparatuses, so perfect and so
delicately adjusted that no one of their organs could be altered,
without the change involving the alteration of all the rest. Darwinism
affirms, on the contrary, that there was no express construction
concerned in the matter; but that among the multitudinous variations of
the Feline stock, many of which died out from want of power to resist
opposing influences, some, the cats, were better fitted to catch mice
than others, whence they throve and persisted, in proportion to the
advantage over their fellows thus offered to them.
Far from imagining that cats exist _in order_ to catch mice well,
Darwinism supposes that cats exist _because_ they catch mice
well--mousing being not the end, but the condition, of their existence.
And if the cat-type has long persisted as we know it, the interpretation
of the fact upon Darwinian principles would be, not that the cats have
remained invariable, but that such varieties as have incessantly
occurred have been, on the whole, less fitted to get on in the world
than the existing stock.
If we apprehend the spirit of the "Origin of Species" rightly, then,
nothing can be more entirely and absolutely opposed to Teleology, as it
is commonly understood, than the Darwinian Theory. So far from being a
"Teleologist in the fullest sense of the word," we should deny that he
is a Teleologist in the ordinary sense at all; and we should say that,
apart from his merits as a naturalist, he has rendered a most remarkable
service to philosophical thought by enabling the student of Nature to
recognise, to their fullest extent, those adaptations to purpose which
are so striking in the organic world, and which Teleology has done good
service in keeping before our minds, without being false to the
fundamental principles of a scientific conception of the universe. The
apparently diverging teachings of the Teleologist and of the
Morphologist are reconciled by the Darwinian hypothesis.