Criticisms on The Origin of Species
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Thomas H. Huxley >> Criticisms on The Origin of Species
This etext was prepared by Amy E. Zelmer.
CRITICISMS ON "THE ORIGIN OF SPECIES"*
by Thomas H. Huxley
[FOOTNOTE] *'The Natural History Review', 1864.
1. UEBER DIE DARWIN'SCHE SCH PFUNGSTHEORIE; EIN VORTRAG, VON A. K
LLIKER. Leipzig, 1864.
2. EXAMINATION DU LIVRE DE M. DARWIN SUR L'ORIGINE DES ESPECES. PAR P.
FLOURENS. Paris, 1864.
In the course of the present year 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'*, to express his high
appreciation of, and general concordance with, Mr. Darwin's views.
[footnote] *'Die Radiolarien: eine Monographie', p. 231.
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 Kolliker, the well-known anatomist and histologist of
Wurzburg; the other by M. Flourens, Perpetual Secretary of the French
Academy of Sciences.
Professor Kolliker'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 Kolliker, 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 Kolliker'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 Kolliker, "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 would 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.
But leaving our own impressions of the 'Origin of Species,' and turning
to those passages especially cited by Professor Kolliker, we cannot
admit that they bear the interpretation he puts upon them. Darwin, if
we read him rightly, does 'not' affirm that every detail in the
structure of an animal has been created for its benefit. His words are
(p. 199):--
"The foregoing remarks lead me to say a few words on the protest lately
made by some naturalists against the utilitarian doctrine that every
detail of structure has been produced for the good of its possessor.
They believe that very many structures have been created for beauty in
the eyes of man, or for mere variety. This doctrine, if true, would be
absolutely fatal to my theory--yet I fully admit that many structures
are of no direct use to their possessor."
And after sundry illustrations and qualifications, he concludes (p.
200):--
"Hence every detail of structure in every living creature (making some
little allowance for the direct action of physical conditions) may be
viewed either as having been of special use to some ancestral form, or
as being now of special use to the descendants of this form--either
directly, or indirectly, through the complex laws of growth."
But it is one thing to say, Darwinically, that every detail observed in
an animal's structure is of use to it, or has been of use to its
ancestors; and quite another to affirm, teleologically, that every
detail of an animal's structure has been created for its benefit. On
the former hypothesis, for example, the teeth of the foetal Balaena
have a meaning; on the latter, none. So far as we are aware, there is
not a phrase in the 'Origin of Species', inconsistent with Professor
Kolliker's position, that "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."
On the contrary, Mr. Darwin writes (Summary of Chap. V.):--
"Our ignorance of the laws of variation is profound. Not in one case
out of a hundred can we pretend to assign any reason why this or that
part varies more or less from the same part in the parents.... The
external conditions of life, as climate and food, etc., seem to have
induced some slight modifications. Habit, in producing constitutional
differences, and use, in strengthening, and disuse, in weakening and
diminishing organs, seem to have been more potent in their effects."
And finally, as if to prevent all possible misconception, Mr. Darwin
concludes his Chapter on Variation with these pregnant words:--
"Whatever the cause may be of each slight difference in the offspring
from their parents--and a cause for each must exist--it is the steady
accumulation, through natural selection of such differences, when
beneficial to the individual, that gives rise to all the more important
modifications of structure which the innumerable beings on the face of
the earth are enabled to struggle with each other, and the best adapted
to survive."
We have dwelt at length upon this subject, because of its great general
importance, and because we believe that Professor Kolliker's criticisms
on this head are based upon a misapprehension of Mr. Darwin's
views--substantially they appear to us to coincide with his own. The
other objections which Professor Kolliker enumerates and discusses are
the following*:--
[footnote] *Space will not allow us to give Professor
Kolliker's arguments in detail; our readers will find a
full and accurate version of them in the 'Reader' for
August 13th and 20th, 1864.
"1. No transitional forms between existing species are known; and known
varieties, whether selected or spontaneous, never go so far as to
establish new species."
To this Professor Kolliker appears to attach some weight. He makes the
suggestion that the short-faced tumbler pigeon may be a pathological
product.
"2. No transitional forms of animals are met with among the organic
remains of earlier epochs."
Upon this, Professor Kolliker remarks that the absence of transitional
forms in the fossil world, though not necessarily fatal to Darwin's
views, weakens his case.
"3. The struggle for existence does not take place."
To this objection, urged by Pelzeln, Kolliker, very justly, attaches no
weight.
"4. A tendency of organisms to give rise to useful varieties, and a
natural selection, do not exist.
"The varieties which are found arise in consequence of manifold
external influences, and it is not obvious why they all, or partially,
should be particularly useful. Each animal suffices for its own ends,
is perfect of its kind, and needs no further development. Should,
however, a variety be useful and even maintain itself, there is no
obvious reason why it should change any further. The whole conception
of the imperfection of organisms and the necessity of their becoming
perfected is plainly the weakest side of Darwin's Theory, and a 'pis
aller' (Nothbehelf) because Darwin could think of no other principle by
which to explain the metamorphoses which, as I also believe, have
occurred."
Here again we must venture to dissent completely from Professor
Kolliker's conception of Mr. Darwin's hypothesis. It appears to us to
be one of the many peculiar merits of that hypothesis that it involves
no belief in a necessary and continual progress of organisms.
Again, Mr. Darwin, if we read him aright, assumes no special tendency
of organisms to give rise to useful varieties, and knows nothing of
needs of development, or necessity of perfection. What he says is, in
substance: All organisms vary. It is in the highest degree improbable
that any given variety should have exactly the same relations to
surrounding conditions as the parent stock. In that case it is either
better fitted (when the variation may be called useful), or worse
fitted, to cope with them. If better, it will tend to supplant the
parent stock; if worse, it will tend to be extinguished by the parent
stock.
If (as is hardly conceivable) the new variety is so perfectly adapted to
the conditions that no improvement upon it is possible,--it will
persist, because, though it does not cease to vary, the varieties will
be inferior to itself.
If, as is more probable, the new variety is by no means perfectly
adapted to its conditions, but only fairly well adapted to them, it
will persist, so long as none of the varieties which it throws off are
better adapted than itself.
On the other hand, as soon as it varies in a useful way, i.e. when the
variation is such as to adapt it more perfectly to its conditions, the
fresh variety will tend to supplant the former.
So far from a gradual progress towards perfection forming any necessary
part of the Darwinian creed, it appears to us that it is perfectly
consistent with indefinite persistence in one estate, or with a gradual
retrogression. Suppose, for example, a return of the glacial epoch and
a spread of polar climatal conditions over the whole globe. The
operation of natural selection under these circumstances would tend, on
the whole, to the weeding out of the higher organisms and the
cherishing of the lower forms of life. Cryptogamic vegetation would
have the advantage over Phanerogamic; Hydrozoa over Corals; Crustacea
over Insecta, and Amphipoda and Isopoda over the higher Crustacea;
Cetaceans and Seals over the Primates; the civilization of the
Esquimaux over that of the European.
"5. Pelzeln has also objected that if the later organisms have proceeded
from the earlier, the whole developmental series, from the simplest to
the highest, could not now exist; in such a case the simpler organisms
must have disappeared."
To this Professor Kolliker replies, with perfect justice, that the
conclusion drawn by Pelzeln does not really follow from Darwin's
premisses, and that, if we take the facts of Palaeontology as they
stand, they rather support than oppose Darwin's theory.
"6. Great weight must be attached to the objection brought forward by
Huxley, otherwise a warm supporter of Darwin's hypothesis, that we know
of no varieties which are sterile with one another, as is the rule
among sharply distinguished animal forms.
"If Darwin is right, it must be demonstrated that forms may be produced
by selection, which, like the present sharply distinguished animal
forms, are infertile, when coupled with one another, and this has not
been done."
The weight of this objection is obvious; but our ignorance of the
conditions of fertility and sterility, the want of carefully conducted
experiments extending over long series of years, and the strange
anomalies presented by the results of the cross-fertilization of many
plants, should all, as Mr. Darwin has urged, be taken into account in
considering it.
The seventh objection is that we have already discussed ('supra', p.
178).
The eighth and last stands as follows:--
"8. The developmental theory of Darwin is not needed to enable us to
understand the regular harmonious progress of the complete series of
organic forms from the simpler to the more perfect.
"The existence of general laws of Nature explains this harmony, even if
we assume that all beings have arisen separately and independent of one
another. Darwin forgets that inorganic nature, in which there can be no
thought of genetic connexion of forms, exhibits the same regular plan,
the same harmony, as the organic world; and that, to cite only one
example, there is as much a natural system of minerals as of plants and
animals."
We do not feel quite sure that we seize Professor Kolliker's meaning
here, but he appears to suggest that the observation of the general
order and harmony which pervade inorganic nature, would lead us to
anticipate a similar order and harmony in the organic world. And this
is no doubt true, but it by no means follows that the particular order
and harmony observed among them should be that which we see. Surely
the stripes of dun horses, and the teeth of the foetal 'Balaena', are
not explained by the "existence of general laws of Nature." Mr.
Darwin endeavours to explain the exact order of organic nature which
exists; not the mere fact that there is some order.
And with regard to the existence of a natural system of minerals; the
obvious reply is that there may be a natural classification of any
objects--of stones on a sea-beach, or of works of art; a natural
classification being simply an assemblage of objects in groups, so as
to express their most important and fundamental resemblances and
differences. No doubt Mr. Darwin believes that those resemblances and
differences upon which our natural systems or classifications of
animals and plants are based, are resemblances and differences which
have been produced genetically, but we can discover no reason for
supposing that he denies the existence of natural classifications of
other kinds.
And, after all, is it quite so certain that a genetic relation may not
underlie the classification of minerals? The inorganic world has not
always been what we see it. It has certainly had its metamorphoses,
and, very probably, a long "Entwickelungsgeschichte" out of a nebular
blastema. Who knows how far that amount of likeness among sets of
minerals, in virtue of which they are now grouped into families and
orders, may not be the expression of the common conditions to which
that particular patch of nebulous fog, which may have been constituted
by their atoms, and of which they may be, in the strictest sense, the
descendants, was subjected?
It will be obvious from what has preceded, that we do not agree with
Professor Kolliker in thinking the objections which he brings forward
so weighty as to be fatal to Darwin's view. But even if the case were
otherwise, we should be unable to accept the "Theory of Heterogeneous
Generation" which is offered as a substitute. That theory is thus
stated:--
"The fundamental conception of this hypothesis is, that, under the
influence of a general law of development, the germs of organisms
produce others different from themselves. This might happen (1) by
the fecundated ova passing, in the course of their development, under
particular circumstances, into higher forms; (2) by the primitive and
later organisms producing other organisms without fecundation, out of
germs or eggs (Parthenogenesis)."
In favour of this hypothesis, Professor Kolliker adduces the well-known
facts of Agamogenesis, or "alternate generation"; the extreme
dissimilarity of the males and females of many animals; and of the
males, females, and neuters of those insects which live in colonies:
and he defines its relations to the Darwinian theory as follows:--
"It is obvious that my hypothesis is apparently very similar to
Darwin's, inasmuch as I also consider that the various forms of animals
have proceeded directly from one another. My hypothesis of the
creation of organisms by heterogeneous generation, however, is
distinguished very essentially from Darwin's by the entire absence of
the principle of useful variations and their natural selection: and my
fundamental conception is this, that a great plan of development lies
at the foundation of the origin of the whole organic world, impelling
the simpler forms to more and more complex developments. How this law
operates, what influences determine the development of the eggs and
germs, and impel them to assume constantly new forms, I naturally
cannot pretend to say; but I can at least adduce the great analogy of
the alternation of generations. If a 'Bipinnaria', a 'Brachialaria', a
'Pluteus', is competent to produce the Echinoderm, which is so widely
different from it; if a hydroid polype can produce the higher Medusa;
if the vermiform Trematode 'nurse' can develop within itself the very
unlike 'Cercaria', it will not appear impossible that the egg, or
ciliated embryo, of a sponge, for once, under special conditions, might
become a hydroid polype, or the embryo of a Medusa, an Echinoderm."
It is obvious, from these extracts, that Professor Kolliker's hypothesis
is based upon the supposed existence of a close analogy between the
phenomena of Agamogenesis and the production of new species from
pre-existing ones. But is the analogy a real one? We think that it
is not, and, by the hypothesis, cannot be.
For what are the phenomena of Agamogenesis, stated generally? An
impregnated egg develops into an asexual form, A; this gives rise,
asexually, to a second form or forms, B, more or less different from
A. B may multiply asexually again; in the simpler cases, however, it
does not, but, acquiring sexual characters, produces impregnated eggs
from whence A, once more, arises.
No case of Agamogenesis is known in which, 'when A differs widely from
B', it is itself capable of sexual propagation. No case whatever is
known in which the progeny of B, by sexual generation, is other than a
reproduction of A.
But if this be a true statement of the nature of the process of
Agamogenesis, how can it enable us to comprehend the production of new
species from already existing ones? Let us suppose Hyaenas to have
preceded Dogs, and to have produced the latter in this way. Then the
Hyena will represent A, and the Dog, B. The first difficulty that
presents itself is that the Hyena must be asexual, or the process will
be wholly without analogy in the world of Agamogenesis. But passing
over this difficulty, and supposing a male and female Dog to be
produced at the same time from the Hyaena stock, the progeny of the
pair, if the analogy of the simpler kinds of Agamogenesis* is to be
followed, should be a litter, not of puppies, but of young Hyenas. For
the Agamogenetic series is always, as we have seen, A: B: A: B, etc.;
whereas, for the production of a new species, the series must be A: B:
B: B, etc. The production of new species, or genera, is the extreme
permanent divergence from the primitive stock. All known Agamogenetic
processes, on the other hand, end in a complete return to the
primitive stock. How then is the production of new species to be
rendered intelligible by the analogy of Agamogenesis?