Let us turn now to the other side. What is opposed to Darwinism in the
biological investigations of the experts of to-day is in part simple
criticism of the Darwinian position as a whole or in some of its details,
and in part constructive individual theories and interpretations of the
evolution of organisms.
A. Fleischmann’s book, “Die Darwinsche Theorie,”(39) is professedly only
critical. He suggests no theory of his own as to the evolution of life in
contrast to Darwin’s; for, as we have already seen in connection with his
earlier book, “Die Deszendenztheorie,” he denies evolution altogether. His
agnostic position is maintained, if possible, more resolutely than before.
Natural science, according to him, must keep to facts. Drawing conclusions
and spinning theories is inexact, and distracts from objective study. The
Darwinian theory of selection seems to him a particularly good example of
this, for it is built up _à priori_ on theories and hypotheses, it stands
apart from experimentation, and it twists facts forcibly to its own ends.
It has, however, to be acknowledged that Fleischmann’s book is without any
“apologetic” intentions. It holds equally aloof from teleology. To seek
for purposes and aims in nature he holds to be outside the business of
science, as Kant’s “Critique of Judgment” suffices to show. After having
been more than a decade under the charm of the theory of selection,
Fleischmann knows its fascination well, but he now regards it as so
erroneous that no one who wishes to do serious work should concern himself
about it at all. Point by point he follows all the details of Darwin’s
work, and seeks to analyse the separate views and theories which go to
make up Darwinism as a whole. Darwin’s main example of the evolution of
the modern races of pigeons from one ancestral form, _Columba livia_, is,
according to Fleischmann, not only unproved but unprovable.(40) For this
itself is not a unified type. The process of “unconscious selection” by
man is obscure, and it is not demonstrable, especially in regard to
pigeon-breeding. It is a hazy idea which cannot be transferred to the
realm of nature. The Malthusian assumption of the necessity of the
struggle for existence is erroneous. Malthus was wrong in his law of
population as applied to human life, and Darwin was still more mistaken
when he transferred it to the organic world in general. It was mere
theory. Statistics should have been collected, and observations instead of
theories should have been sought for. The alleged superabundance of
organisms is not a fact. The marvellously intertwined conditions in the
economy of nature make the proportion of supply and demand relatively
constant. And even when there is actual struggle for existence, advantages
of situation,(41) which are quite indifferent as far as selection is
concerned, are much more decisive than any variational differences. The
theory does not explain the first origin of new characters, which can only
become advantageous when they have attained to a certain degree of
development. As to the illustrations of the influence of selection given
by Darwin, from the much discussed fictitious cases, in which the fleet
stags select the lithe wolf, to the marvellous mutual adaptations of
insects and flowers, Fleischmann objects that there is not even
theoretical justification for any one of them. The spade-like foot of the
mole is not “more useful” than the form of foot which probably preceded it
(_cf._ Goette), it is merely “different.” For when the mole took to
burrowing in the earth and adapting itself to that mode of life, it _ipso
facto_ forfeited all the advantages of living above ground. The postulated
myriads of less well-adapted forms of life are no more to be found to-day
than they are in the fauna and flora of palæontological times. The famous
giraffe story has already been disposed of by Mivart’s objections. As to
the whales, it is objected that the earliest stages of their whalebone and
their exaggerated nakedness can have been of no use, and a series of other
alleged selective effects of “utility” are critically analysed. The
refutation of the most brilliant chapter in the Darwinian theory, that on
protective coloration and mimicry, is very insufficient. A long concluding
chapter sums up the fundamental defects of the Darwinian theory.
For the most part, Fleischmann simply brings forward objections which have
been urged against the theory of selection from the first, either by
naturalists or from other quarters. The chief and the most fatal of these
which are still current are the following: The theory of selection does
not explain the actually existing discontinuity of species. The real
characteristics which distinguish species from species are in innumerable
cases quite indifferent from the point of view of “utility” (Nägeli,
Bateson). “Selection preserves the good and weeds out the bad.” But where
does the good come from? (De Vries). The first beginnings of what may
later be useful are almost always useless. The theory of selection might
perhaps explain the useful qualities, but not the superfluous, useless, or
directly injurious characters which actually exist. Confirmation of the
theory of descent may be found in the palæontological record, but it
affords none of the theory of selection. Natural selection is continually
being neutralised by subsequent inter-crossing and reversion. Natural
selection may indeed prevent degeneration within the limits of the species
by weeding out what is weak and bad, but it is powerless beyond these
limits, and so forth.(42)
These ever-repeated and ever-increasing objections are purely critical. As
this is true of Fleischmann’s whole book, it is therefore unsatisfactory.
It leaves everything in the mist, and puts nothing in place of what it
attempts to demolish. But attempts are being made in other quarters,
especially among the Lamarckians, to build up an opposition theory.
Lamarckism and Neo-Lamarckism.
The “Lamarckian” view as opposed to the Darwinian continues to hold its
own, and indeed is more ardently supported than ever. On this view,
evolution has been accomplished not by a laborious selection of the best
which chanced to present itself—a selection in relation to which organisms
remained passive, but rather through the exertions of the organisms
themselves. It has been especially through the use and exercise of the
various organs in response to the requirements of life, through the
increased exercise of physical and mental functions, that the organism has
adapted itself more diversely and more fully to the conditions of its
life. What one generation acquired in differentiation of structure, in
capacities and habits, through its own exertions, it handed on to the
next. By cumulative inheritance there ultimately arose the fixed specific
characters, and the diversity and progressive gradations of organisms have
gone hand in hand with an ever increasing activity. And as with the
physical so it has been with the mental. Through continual use and
exercise of the functions their capacity has been increased and modified.
Through the frequent repetition of voluntary actions necessary to life the
habitual use of them has come about. Habits that have become fixed are
correlated with habitual psychical predispositions. These, gradually
handed on by inheritance to the descendants, have resulted in the
marvellous instincts of animals. Instinct is inherited habit that has
become fixed. Corresponding to this there is on the other hand the
recognition—in theory at least—that the disuse of an organ, the
non-exercising of a function leads to degeneration of structure and so
co-operates in bringing about a gradual but persistent modification of the
features and constitution of organisms.
These views, which have grown out of Lamarck’s fundamental ideas
(“Philosophie zoologique,” 1809) are now usually associated with the
theory advanced chiefly by Etienne Geoffrey St. Hilaire (“Philosophie
zoologique,” 1830), the opponent of Cuvier, and the ally of Goethe, of the
direct influence of the _monde ambiant_. The “surrounding world,” the
influences of climate, of locality, of the weather, of nutrition, of
temperature, of the salinity of the water, of the moisture in the air, and
all other conditions of existence, influence the living organism. And they
do so not indirectly, as is implied in the process of selection, simply
playing the part of a sieve, and not themselves moulding and transforming,
but _directly_ by necessitating the production of new developments in the
living substance, new chemical and physiological activities, new groupings
and changes of form, and new organs.
Darwin himself did not regard these two theories as opposed to the theory
of selection, but utilised them as subsidiary interpretations. It is
obvious, however, that at bottom they conceal an essentially different
fundamental idea, which, if followed out to its logical consequences,
reduces the “struggle for existence” to at most a wholly indifferent
accessory circumstance. Weismann felt this, and hence his entirely
consistent endeavours to show by great examples, such as the origin of
flowers, the mutual adaptations of flowers and insects, the phenomena of
mimicry, and many other cases, that neither the Lamarckian nor any other
factor in evolution, except only natural, passive selection, suffices as
an interpretation. From the Darwinian standpoint he is absolutely right,
and must needs speak of the “omnipotence of natural selection,” for it
must either be omnipotent, or it must give place to the other two factors,
and retain only the significance we attributed to it in another connection
(p. 157), which amounts to saying none at all. It is obvious enough why
the discussion as to these factors should centre round the question of the
“inheritance of acquired characters,” “acquired” either through the use or
disuse of organs, the exercise or non-exercise of functions, or through
the stimuli of the external world.
The neo-Lamarckian conflict with Darwinism has become more and more acute
in recent times, and the neo-Lamarckians have sometimes passed from
contrasting rival interpretations to excluding the Darwinian factor
altogether. As the particular champion of the neo-Lamarckian view, we must
name Th. Eimer, the recently deceased Tübingen zoologist. His chief work
is in three volumes, entitled “Die Entstehung der Arten auf Grund von
Vererbung erworbener Eigenschaften, nach Gesetzen organischen
Wachsens.”(43) It is a polemic against Weismannism in all details, even to
the theory of “germinal selection.” Eimer follows in the footsteps of St.
Hilaire, and shows what a relatively plastic and sensitive creature the
organism is to the surrounding world, the conditions of nutrition and
other such influences. There is in this connection a particularly
instructive chapter on the physiological and other variations brought
about by external influences which act as “stimuli of the nervous system.”
The whole theory of Lamarck and St. Hilaire transcends—notwithstanding the
protests of Eimer to the contrary—the categories of the mechanical theory
of life, and this chapter does so in particular. The array of facts here
marshalled as to the spontaneous self-adaptation of organisms to their
environment—in relation to colour mainly—forms the most thoroughgoing
refutation of Darwinism that it is possible to imagine. It is shown, too,
by a wealth of examples from osteology, how use (and the necessities of
the case—a consideration which again goes beyond the bounds of mere
Lamarckism) may modify, increase or diminish vertebræ, ribs, skull and
limbs, in short, the whole skeleton.
Kassowitz is equally keen and convinced in his opposition to natural
selection, and in his comprehensive “Allgemeine Biologic”(44) he attacks
orthodox Darwinism from the neo-Lamarckian standpoint. The whole of the
first volume is almost chapter for chapter a critical analysis, and the
polemical element rather outweighs his positive personal contribution. He
criticises very severely all attempts to carry the Darwinian principle of
explaining adaptations into internal and minute details, arguing against
Roux’s “Struggle of Parts” and Weismann’s “Germinal Selection.” And though
he himself maintains very decidedly that the ultimate aim of biology is to
find a mechanical solution of the problem of life, he criticises the
modern hypotheses in this direction without prejudice, and declares them
unsuccessful and insufficient, inclining himself towards the
“neo-vitalistic reaction” in its most recent expression. Along with Eimer
and Kassowitz, we may name W. Haacke, especially in relation to his views
on the acquisition and transmission of functional modifications and his
thoroughgoing denial of Darwinism proper. But his work must be dealt with
later in a different connection.(45)
These neo-Lamarckian views give us a picture of the evolution of the world
that is much more convincing than the strictly Darwinian one. Instead of
passive and essentially unintelligent “adaptation” through the sieve of
selection, we have here direct self-adaptation of organisms to the
conditions of their existence, through their own continual restless
activity and exertion, an ascent of their own accord to ever greater
heights and perfections. A theory of this kind might easily form part of a
religious conception of the world. We might think of the world with
primitive tendencies and capacities, in which the potentialities of its
evolution were implied, and so ordered that it had to struggle by its own
exertions to achieve the full realisation of its possibilities, to attain
to ever higher—up to the highest—forms of Being. The process of nature
would thus be the direct anticipation of what occurs in the history of man
and of mind. And the task set to the freedom of individual men, and to
mankind as a whole, namely, to work out their own nature through their own
labour and exertion, and to ascend to perfection—this deepest meaning of
all individual and collective existence—would have its exact prelude and
preparation in the general nature and evolution of all living creatures.
The transition from these theories of nature to a teleological outlook
from the highest and most human point of view is so obvious as to be
almost unavoidable. And although a natural science which keeps to its own
business and within its own boundaries has certainly no right to make this
transition for itself, it has still less right to prevent its being made
outside of its limits.
Theory of Definite Variation.
But the question now arises, whether both Darwinism and Lamarckism must
not be replaced, or at least reduced to the level of accessory theories
and factors, by another theory of evolution which was in the field before
Darwin, and which since his time has been advanced anew, especially by
Nägeli, and has now many adherents who support it in whole or in part.
This view affects the very foundations of the Darwinian doctrine. The
theory of “indefinite” variation, bringing about easy transitions and
affecting every part of the organism separately, which is the necessary
correlate of the “struggle for existence,” is rejected altogether.
Evolution takes place only along a few definite lines, predetermined
through the internal organisation and the laws of growth. It is wholly
indifferent to “utility,” and brings forth only what it must according to
its own inner laws, not seldom even the monstrous. According to this view,
new species arise, not in easy transition, but with a visible leap, by a
considerable and far-reaching displacement of the organic equilibrium.
What Darwin calls the correlation of parts, and in no way denies, is here
maintained in strong opposition to his doctrine of the isolated variation
of individual parts; every member or character of the organism depends
upon others, and variation of one affects many, and in some way all of the
rest.
This theory is for the most part intended by its champions to be purely
naturalistic. But every one of its points yields support to teleological
considerations, most obviously so the concrete instances of correlation.
If any one were to attempt to make a theory of evolution from a decidedly
teleological standpoint, he would probably construct one very similar to
the one we are now considering.
It is noteworthy that it has generally been the botanists who have
especially supported these views of saltatory evolution in a definite
direction and according to internal law, who have therefore tended to
react most strongly from Darwinism. We find examples in Nägeli’s large and
comprehensive work, “Mechanisch-physikalische Theorie der
Abstammungslehre”; and, before him, in Wigand’s “Darwinismus und die
Naturforschung Newton’s und Cuvier’s”; in von Kölliker’s “Heterogenesis”;
in von Baer’s “Endeavour after an End”; in the chapter added by the
translator, Bronn, to the first German edition of the “Origin of Species,”
where he urges weighty objections against the theory of selection, and
refers to the “innate impulse to development, persistently varying in a
definite direction”; in Askenasy’s oft-quoted “Beiträge zur Kritik der
Darwinschen Lehre,” also referring to “variation in a definite direction,”
for instance, in flowers; in Delpino’s views, and in the works of many
other older writers. But we must leave all these out of account here,
since we are concerned only with the present state of the question.
De Vries’s Mutation-theory.
The work that has probably excited most interest in this connection is De
Vries’ “Die Mutationstheorie: Versuche und Beobachtungen über die
Entstehung von Arten im Pflanzenleben.”(46) In a short preliminary paper
he had previously given some account of his leading experiments on a
species of evening primrose (_Œnothera lamarckiana_), and the outlines of
his theory. In the work itself he extends this, adding much concrete
material, and comparing his views in detail with other theories. Darwin,
he says, had already distinguished between variability and mutability; the
former manifesting itself in gradual and isolated changes, the latter in
saltatory changes on a larger scale. The mistake made by Wallace and by
the later Darwinians has been that they regarded this latter form (“single
variation”) as unimportant and not affecting evolution, and the former as
the real method of evolutionary process. That fluctuating individual
variations do occur De Vries admits, but only within narrow limits, never
overstepping the type of the species. Here De Vries utilises the recent
statistical investigations into the phenomena of individual variation and
their laws, as formulated chiefly by Quetelet and Bateson, which were
unknown to Darwin and the earlier Darwinians. The actual transition from
“species to species” is made suddenly, by mutation, not through variation.
And the state of equilibrium thus reached is such a relatively stable one
that individual variations can only take place within its limits, but can
in no way disturb it.
De Vries marshals a series of facts which present insurmountable
difficulties to the Darwinian theory, but afford corroboration of the
Mutation theory. In particular, he brings forward, from his years of
experiment and horticultural observation, comprehensive evidence of the
mutational origin of new species from old ones by leaps, and this not in
long-past geological times, but in the course of a human life and before
our very eyes. The main importance of the book lies in the record of these
experiments and observations, rather than in the theory as such, for the
way had been paved for it by other workers.
In contrast to Darwinism, De Vries states the case for “Halmatogenesis”
(saltatory evolution) and “Heterogenesis” (the production of forms unlike
the parents), taking his examples from the plant world, but his attitude
to Darwinism is conciliatory throughout. Eimer, on the other hand, is
sharply antagonistic, especially to Weismann; he takes his proofs from the
animal kingdom, and in the second volume of his large work already
mentioned, which deals with the “orthogenesis of butterflies,” he attempts
to set against the Darwinism “chance theory,” a proof of “definitely
directed evolution,” and therefore of the “insufficiency of natural
selection in the formation of species.”
Eimer’s Orthogenesis.
Organisation is due to internal causes. Structural characters crystallise
out, as it were. “Orthogenesis,” or the definitely determined tendency of
evolution to advance in a few directions, is a law for the whole of the
animate world. In active response to the stimuli and influences of the
environment the organism expresses itself in “organic growth” without any
relation to utility. Butterflies in particular, and especially their
markings and coloration, are taken as illustrations. In the Darwinian
theory of “mimicry” these played a brilliant part. The great resemblance
to leaves, to dried twigs, or to well-protected species which are secure
from enemies, was regarded as the most convincing proof of the operation
of natural selection. But Eimer shows that markings, striping, spots, the
development of pattern, and the alleged or real resemblances to leaves,
are really subject to definite laws of growth, in obedience to which they
gradually appear, developing according to their own internal laws, varying
and progressing altogether by internal necessity, and without any
reference to advantage or disadvantage, In association with this
orthogenesis, Eimer recognises halmatogenesis, correlation and
“genepistasis” (coming to a standstill at a fixed and definite stage), and
these seem to him to make the Darwinian theory utterly impossible. The
text and the illustrations of the book show how, in the sequence of
evolution (according to Eimer’s laws of transformation), the groupings of
stripes, bands, and eye-spots must have appeared on the butterfly’s wing,
how convex or concave curvings of the contour must have come about at
certain points, so that the form of a “leaf” and the lines of its venation
resulted, how the eye-spots must have been moulded and shunted, so that
they produced the effect of rust or other spots on withered leaves.
Particular interest attaches to the detailed arguments against the idea
that the butterfly must receive some advantage from its “mimicry.” Even
the Darwinians have to admit that in a whole series of cases the advantage
is not obvious. They talk with some embarrassment of “pseudomimicry.” Some
butterflies that are supposed to be protected have the protective markings
on the underside, so that these are actually hidden when the insects are
flying from pursuing birds. Many of the leaf-like butterflies are not
wood-butterflies at all, but meadow species,(47) and so Eimer’s arguments
continue.
A specially energetic fellow-worker on Eimer’s line is W. Haacke, a
zoologist of Jena, author of “Gestaltung und Vererbung,” and “Die
Schöpfung des Menschen und seiner Ideale.”(48) In the first of these works
Haacke combats, energetically and with much detail, Weismann’s
“preformation theory,” and defends “epigenesis,” for which he endeavours
to construct graphic diagrams, his aim being to make a foundation for the
inheritance of acquired characters, definitely directed evolution,
saltatory, symmetrical, and correlated variation.
The principles of the new school are very widespread to-day, but we cannot
here follow their development in the works of individual investigators,
such as Reinke, R. Hertwig, O. Hertwig, Wiesner, Hamann, Dreyer, Wolff,
Goette, Kassowitz, v. Wettstein, Korschinsky, and others.(49)
The Spontaneous Activity of the Organism.
What is particularly luminous in all the theories that express the most
recent anti-Darwinian tendency is that they tend to bring into prominence
the mysterious powers of living organisms, by means of which, instead of
passively waiting for natural selection and the continual accumulation of
unceasing variations, they are able spontaneously and of themselves to
bring forth what is necessary for self-maintenance, often what is new and
different, of course not unlimitedly, but with considerable freedom and
often with a surprising range of possibilities. It is, perhaps, partly the
fault of the one-sidedness of strict Darwinism that this consideration has
been so slowly brought into prominence and subjected to investigation and
experiment. It is bound up with the capacity that all forms of life have
of reacting spontaneously to “stimuli” and, to a certain extent, of
helping themselves if the conditions of existence be unfavourable. They
are able, for instance, to produce protective adaptations against cold or
heat, to “regenerate” lost parts, often to replace entire organs that have
been lost, and, under certain circumstances, to produce new organs
altogether. If all this be true, it seems almost like caprice to follow
only the roundabout theory of the struggle for existence, and not to take
account of these spontaneous capacities of the living organism directly
and before all other factors in the attempt to explain evolution. There is
no end to the illustrations that are being adduced, that must force
investigation to pass from merely superficial considerations of the
struggle for existence type to the deeper and more real problems
themselves.
An effectively modified and adapted type of Alpine flora has not been
evolved by a laborious process of selection lasting for many thousand
years; the organism may quickly and immediately produce the new characters
by its own reaction. Crustaceans gradually transferred from a salt-water
to a fresh-water habitat, or conversely, produce in a few generations the
type of a new “species” with correlated variations (Schmankewitsch). Birds
weaned by careful experiment from a diet of seeds to one of flesh, or
conversely, produce changes of effective correlation and adaptation in the
characters of their alimentary system. Plants that have been deprived of
their normal organs for absorbing water and prevented from growing new
ones produce entirely new and effective “hydatodes.”(50)
It is instructive to notice that Darwinism seems likely to be robbed of
its stock illustration, namely, “protective coloration.” By its own
internal power of reaction, and sometimes within one generation, and even
in the lifetime of an individual, an organism may assume the colour of the
substratum beneath it (soles, grasshoppers), of its surroundings (Eimer’s
tree frogs), the colour and spottiness of the granite rock on which it
hangs, the colour of the leaves and twigs among which it lives (Poulton’s
butterfly pupæ), and even that of the brightly coloured sheets of paper
amidst which it is kept imprisoned. Certain spiders assume a white, pink,
or greenish “protective coloration” corresponding to the tinted blossom of
the plants which they frequent, and so on.(51) Eimer alleged that direct
psychical factors co-operated in bringing about these changes. In any
case, all this carries us far beyond the domain of mere naturalistic
factors into the mystery of life itself. Even what is called the
“influence of the external world,” and the “active acquirement of new
characters,” have their basis and the reason of their possibility in this
domain. And the whole domain is saturated through and through with
“teleology.”
A recognition of the impressive secret of the organism led Gustav Wolff to
become a very pronounced critic of Darwinism, especially in the form of
Weismannism. As far back as 1896, in a lecture “On the present position of
Darwinism,” in which he dealt only with Weismann, he criticised and
analysed that author’s last attempt to uphold Darwinism by the
construction of his theory of “germinal selection.” He concluded with the
wish:
“That a spirit of earnestness would once more enter into biological
investigation, which would no longer attempt to find in nature just what
it wanted to find, but would be ready to follow truth at all costs, and to
approach the riddle of life with an open mind.”
His “Beiträge zur Kritik der Darwinischen Lehre,” which appeared first as
papers in the “Biologisches Centralblatt,” did not see the light in book
form until 1898. The doctrine of selection was regarded as so unassailable
that no publisher would take the risk of the book. Its appearance is a
sure indication of the general modification of opinions that had taken
place in the interval. The first and second essays are merely critical
objections to the theory of selection, very similar to those frequently
urged before, but more precisely stated.(52) The third is intended to show
that there is in the forms of life themselves, as a faculty of adaptation
peculiar to them, a primary purposiveness, which is unquestionably active
throughout the lifetime and development of every individual, but which is
also the deepest cause of “phylogenesis,” or the formation of a race. This
doctrine makes both the Darwinian and Lamarckian theories merely
secondary. For the phenomena which suggest the Lamarckian interpretation
presuppose this most essential factor—the primary adaptiveness. Wolff
concludes with a very striking instance—discovered by himself—of this
primary adaptiveness of the organism—the regeneration of the lens in the
newt’s eye.
More comprehensively, but from a precisely similar standpoint, Driesch has
followed up the discussion of this problem.(53) He is, of all modern
investigators, perhaps the one who has most persistently and thoroughly
worked out the problem of causal and teleological interpretation, and he
has also thrown much light on the scientific and epistemological aspects
of the problem. That he could, in a recent volume of the “Biologisches
Zentralblatt,” write a respectful and sympathetic exposition of the
Hegelian nature-philosophy—as regards its aims, though not its methods—is
as remarkable a symptom as we can instance of the modern trend of views
and opinions.(54)
Contrast Between Darwinian and Post-Darwinian Views.
The new views that have thus arisen have been definitely summarised and
clearly contrasted with Darwinism by the botanist Korschinsky. He died
before completing his general work, “Heterogenesis und Evolution,” but he
has elsewhere(55) given an excellent summary of his results, which we
append in abstract.
DARWIN. (1) Everything organic is capable of variation. Variations arise
in part from internal, in part from external causes. They are slight,
inconspicuous, individual differences.
KORSCHINSKY AND THE MODERNS. (1) Everything organic is capable of
variation. This capability is a fundamental, inherent character of living
forms in general, and is independent of external conditions. It is usually
kept latent by “heredity,” but occasionally breaks forth in sudden
variations.
DARWIN. (2) The struggle for existence. This combines, increases, fixes
useful variations, and eliminates the useless. All the characters and
peculiarities of a finished species are the results of long-continued
selection; they must therefore be adapted to the external conditions.
KORSCHINSKY AND THE MODERNS. (2) Saltatory variations.—These are, under
favourable circumstances, the starting-point of new and constant races.
The characters may sometimes be useful, sometimes quite indifferent,
neither advantageous nor disadvantageous. Sometimes they are not in
harmony with external circumstances.
DARWIN. (3) The species is subject to constant variation. It is
continually subject to selection and augmentation of its characters. Hence
again the origin of new species.
KORSCHINSKY AND THE MODERNS. (3) All fully developed species persist, but
through heterogenesis a splitting up into new forms may take place, and
this is accompanied by a disturbance of the vital equilibrium. The new
state is at first insecure and fluctuating, and only gradually becomes
stable. Thus new forms and races arise with gradual consolidation of their
constitution.
DARWIN. (4) The sharper and more acute the effect of the environment, the
keener is the struggle for existence, and the more rapidly and certainly
do new forms arise.
KORSCHINSKY AND THE MODERNS. (4) Only in specially favourable conditions,
only when the struggle for existence is weak, or when there is none, can
new forms arise and become fixed. When the conditions are severe no new
forms arise, or if they do they are speedily eliminated.
DARWIN. (5) The chief condition of evolution is therefore the struggle for
existence and the selection which this involves.
KORSCHINSKY AND THE MODERNS. (5) The struggle for existence simply
decimates the overwhelming abundance of possible forms. Where it occurs it
prevents the establishment of new variations, and in reality stands in the
way of new developments. It is rather an unfavourable than an advantageous
factor.
DARWIN. (6) If there were no struggle for existence there would be no
adaptation, no perfecting.
KORSCHINSKY AND THE MODERNS. (6) Were there no struggle for existence,
there would be no destruction of new forms, or of forms in process of
arising. The world of organisms would then be a colossal genealogical tree
of enormous luxuriance, and with an incalculable wealth of forms.
DARWIN. (7) Progress in nature, the “perfecting” of organisms, is only an
increasingly complex and ever more perfect adaptation to the external
circumstances. It is attained by purely mechanical methods, by an
accumulation of the variations most useful at the time.
KORSCHINSKY AND THE MODERNS. (7) The adaptation which the struggle for
existence brings about has nothing to do with perfecting, for the
organisms which are physiologically and morphologically higher are by no
means always better adapted to external circumstances than those lower in
the scale. Evolution cannot be explained mechanically. The origin of
higher forms from lower is only possible if there is a tendency to
progress innate in the organism itself. This tendency is nearly related to
or identical with the tendency to variation. It compels the organism to
perfect itself as far as external circumstances will permit.
All this implies an admission of evolution and of descent, but a setting
aside of Darwinism proper as an unsuccessful hypothesis, and a positive
recognition of an endeavour after an aim, internal causes, and teleology
in nature, as against fortuitous and superficial factors. This opens up a
vista into the background of things, and thereby yields to the religious
conception all that a study of nature can yield—namely, an acknowledgment
of the possibility and legitimacy of interpreting the world in a religious
sense, and assistance in so doing.
The most important point has already been emphasised. Even if the theory
of the struggle for existence were correct, it would be possible to
subject the world as a whole to a teleological interpretation. But these
anti-Darwinian theories now emerging, though they do not directly induce
teleological interpretation, suggest it much more strongly than orthodox
Darwinism does. A world which in its evolution is not exposed, for good or
ill, to the action of chance factors—playing with it and forcing it hither
and thither—but which, exposed indeed to the most diverse conditions of
existence and their influences, and harmonising with them, nevertheless
carries implicitly and infallibly within itself the laws of its own
expression, and especially the necessity to develop upwards into higher
and higher forms, is expressly suited for teleological consideration, and
we can understand how it is that the old physico-teleological evidences of
the existence of God are beginning to hold up their heads again. They are
wrong when they try to demonstrate God, but quite right when they simply
seek to show that nature does not contradict—in fact that it allows room
and validity to—belief in the Highest Wisdom as the cause and guide of all
things natural.
As far as the question of the right to interpret nature teleologically is
concerned, it would be entirely indifferent whether what Korschinsky calls
“the tendency to progress,” and the system of laws in obedience to which
evolution brings forth its forms, can be interpreted “mechanically” or
not; that is to say, whether or not evolution depends on conditions and
potentialities of living matter, which can be demonstrated and made
mechanically commensurable or not. It may be that they can neither be
demonstrated nor made mechanically commensurable, but lie in the
impenetrable mystery inherent in all life. Whether this mystery really
exists, and whether religion has any particular interest in it if it does,
must be considered in the following chapter.