The Old Riddle And The Newest Answer Part 10

Such are not by any means the only instances in which the Darwinist can appeal to Nature for facts with which his theory well agrees, and which therefore so far furnish a persuasive argument in its favour; but these are perhaps the chief ones, and the best known, and may serve as representative of their cla.s.s which it is impossible for us to examine in detail.

It now remains to enquire how far, from the point of view of Science, with which alone we are concerned, the Darwinian hypothesis can make good its claim to our acceptance. When we proceed accordingly to examine the grounds upon which it rests, it must be confessed that as we do so it becomes increasingly difficult to understand how such a theory has been able to obtain such wide acceptance, especially on the ground that scientific evidence is in its favour.

On the very threshold of any such enquiry lies a difficulty the gravity of which seems to be strangely overlooked. Darwinism by its own confession knows nothing of Origins, not even of the Origin of Species itself. There must be life already existing before Natural Selection has anything to select; there must be eyes and honey-cells of some kind, before they can be improved; there must be Species, before one can be transformed into another. Is it not evident, however, that the cause--of whatever kind it may be--which brought any of these into being, must have _something_,--not to say everything,--to do with the capacities and potentialities by which its future history is conditioned? But this supreme and vital factor Mr. Darwin entirely eliminates from his calculation. In his system, the initiating force has no more to do with the subsequent career of its productions, than has the gas which lifts a balloon with the direction in which it travels. It is not, on his theory, as the impulse which, besides raising from earth an arrow or rifle bullet, directs it to a goal, but, on the contrary, an organism once launched on its course is left to be driven hither and thither and twisted into this form and that, as clouds are by the wind. For the variations through which transformations are wrought, Darwin could find no better epithet than "fortuitous," and it is laid down by his staunchest disciples that if such variations be predetermined towards certain results, there is an end of Darwinism.

It is not easy to understand how any theory can be deemed satisfactory which thus ignores the initial force, of whose existence and potency we have far clearer evidence than of any other.

When we turn from its omissions to study Darwinism as it is, obviously, in the first place, still, more than forty years since it was given to the world, it remains only an hypothesis, based not upon observation or experiment but speculation. In no single instance, past or contemporary, is one species known to have originated from another. The fact upon which Mr. Darwin primarily relies is that of variation. Undoubtedly amongst both plants and animals the offspring are not mere slavish reproductions of their parents, as if cast in the same mould, but exhibit individual differences, working upon which in domesticated instances, man can by selection produce wonderful varieties, as has already been admitted. But, as M. de Quatref.a.ges says,[191] this tells us no more than that species admit of variation; it does not prove that they are capable of transformation, which is the whole point. Certainly, such transformation has never within our knowledge been effected. No breeder or fancier has succeeded, or can hope to succeed, in producing a new species. Moreover, as was pointed out by a critic whose ability Mr.

Darwin himself candidly acknowledged,[192] the range of variability as we find it in any species is strictly limited, and although at first it is easy,--in the case of some few animals or plants,--to make great changes in particular directions, by selective breeding, it becomes more and more difficult as we proceed to continue in the same line. If, for instance, in the case of pigeons, a bird can be produced in six years with head and beak only one-half the size of those whence the process started, are we to say that in twelve years their bulk will be reduced to a quarter, and in twenty-four to an eighth? No one could suppose anything so absurd. Mr. Darwin would answer, that he relies upon the vast periods of geologic time to produce alterations such as we cannot possibly attempt within the few years at our disposal. But, it is replied, no length of time will avail anything for such a purpose, unless there be some force to produce variations in the required direction, to the required extent. Such a force is not proved to exist--all the evidence is against it. Where art is most practised in improvement of breeds, or the obtaining of any peculiarities--as with the speed of racehorses, the size of toy-terriers, or the "points" of prize cattle, it becomes most strikingly apparent that we have reached a limit beyond which species will not vary. And until such a cause as we require is fully proved to exist, its supposed effects cannot be made the basis of scientific argument.

A given animal or plant, [says the Reviewer] appears to be contained, as it were, within a sphere of variation; one individual lies near one portion of the surface, another individual near another part of the surface; the average animal at the centre. Any individual may produce descendants varying in any direction, but is more likely to produce descendants varying towards the centre of the sphere, and the variations in that direction will be greater in amount than the variations towards the surface. Thus a set of racers of equal merit indiscriminately breeding will produce more colts and foals of inferior than of superior breed, and the falling off of the degenerate will be greater than the improvement of the select (p. 282).

Similarly M. Blanchard declares:[193]

All investigation and observation make it clear that, while the variability of creatures in a state of nature displays itself in very different degrees, yet in its most astonis.h.i.+ng manifestations it remains confined within a circle beyond which it cannot pa.s.s.

And the facts of nature, as we know them, far from favouring the instability of species, exhibit a tenacity of form compelling us to treat them as practically immutable. Thus, as Mr. Carruthers points out,[194] in the notoriously variable genus _Salix_, or willow-tribe, which seems to be actively advancing towards a multiplication of its subdivisions, sub-genera, species, varieties, and hybrid forms,--one species is found, _S. polaris_, dating from before the Glacial Epoch, which has been driven from England and other lands, by climatic changes, to within the Arctic circle of both Hemispheres,--yet amid this stress of circ.u.mstances has preserved its specific ident.i.ty, down even to the casual variations, which might be supposed to furnish the starting-points for new developments. Yet in this tribe, if anywhere, evidence of specific evolution might be looked for.[195]

Other instances seem to show that even under new and trying conditions those creatures survive best which keep closest to the central family type, not those which diverge in any direction. Thus, of European sparrows introduced in America, Mr. b.u.mpus writes:[196]

Natural Selection is most destructive of those birds which have departed most from the ideal type, and its activity raises the general standard by favouring those birds which approach the structural ideal.

Variation supplies the raw material upon which Natural Selection is supposed to work. When we turn to examine the process by which its results should be produced, we find, quite apart from the above difficulties, a crop of others still more formidable.

It must be remembered, that the variations on which Natural Selection must work are in each instance extremely minute, well-nigh infinitesimal. Mr. Darwin was as strongly opposed to the idea of Nature making sudden bounds, as to that of a predetermined course of development. But, he argued, an extra chance of living, however slight, must necessarily tell in the long run, the theory of probabilities giving results as certain as any others in mathematics, and, according to these, we may confidently say that, given sufficient time, the favoured individuals would infallibly distance their compet.i.tors.

The impressiveness of such an argument depends upon its seemingly mathematical character, which is however wholly fallacious, for the probabilities are all the other way. It is perfectly true that a beneficial variation however slight will confer on its happy possessor a corresponding advantage in the struggle for life, as compared with each _individual_ of the non-favoured herd, but, as to that herd collectively, the chances would, on the contrary, ensure that _some_ of its members should outlive the favoured one. Let us even imagine the advantage of the latter to be very great, great enough to double his chances, so that the odds on his surviving each of his fellows will be two to one. Yet if there be a dozen of them to contend with, the odds will be six to one _against_ his surviving the lot. And what of the actual case of minutest benefits conferred by variation? In order to give them even an equal chance of survival, the numbers of those possessing such advantages must be large in proportion as the advantages themselves are small. Thus, if a variation increases the chance of life by one-thousandth part, so that the odds on its possessor are 1001, against 1000 on each non-possessor, yet unless the number of possessors be to that of non-possessors as 1,000 to 1,001, their collective chances will not even be equal. As it is quite absurd to suppose that casual variations could ever occur in such wholesale fas.h.i.+on, how can it be supposed that, were Natural Selection the only factor operating, minute advantages could be acc.u.mulated by variation even in the simplest cases?

But it is also hard to suppose that in any actual case is the matter so simple as it appears to our limited comprehension. To take for instance the above example of the giraffe. It is very well to have a neck that will reach high-branches of a tree,--but this is not everything. For the mere prolongation of life, much else is required, fleet limbs to distance lions, and keen senses, sight, hearing, and smell, to give warning of the approach of human or other hunters, to say nothing of the extra strengthening of muscles and bones which increased size and weight demands. Unless, however, improvements in all these respects happened casually to concur in the same individual, which could scarcely happen, it is clear that each would militate against the others, for the survival of an individual beneficially developed in one respect, would tend to the extinction of other beneficial developments, possessed by individuals whom he overcame in the struggle for life.

Even the case of the insular insects is by no means so plain as might at first sight appear. There can be no doubt that wings are of _some_ advantage, or on no system could they be supposed to exist. Nor do their advantages cease because disadvantages outweigh them. If some insects are blown out to sea when flying, others will doubtless perish in one way or another because they cannot fly. It may even be that those which can fly _best_ will survive, as being able to make head against a breeze which overpowers others. Natural Selection will thus have many arrows in its quiver, some of which must reach the wrong objects.

Still more clearly does this appear in the case of complex structures in which, if they were produced as Mr. Darwin supposes, variation must have hit simultaneously upon independent contrivances, without each of which all the others would be useless and confer no benefit at all. In the eye, for example, to mention but one or two of innumerable similar points, it would be of no avail to have a retina, even such as has been described, without a lens to throw an image upon it, set just at the proper distance, and provided with muscles to alter its shape according to the distance of the object. How can Natural Selection be even conceived to have set to work on such a task as this?

It is still more fundamental to observe that, according to Mr. Darwin's own showing, Natural Selection is purely negative in its action. "If it does select, it selects for death and not for life."[197] It can originate nothing, but only destroy. All that it does for favoured races is to spare them while it sweeps away others, and the sole benefit they derive from it is to have more ample resources upon which to draw. But as for anything they possess in the way of structure or character, they must derive it entirely from themselves--Natural Selection can no more confer it, than the labourer who weeds a garden bed makes the flowers that grow there. Let it be imagined that the first human beings on earth, any number of thousand years ago, planted a garden, and determined to produce a rose, by eliminating every plant that did not show some promise of progress rose-wards. Let the gardeners have been endowed with ac.u.men sufficient to detect every symptom of such a tendency, and let their operations have been carried on without interruption to this day,--it is obvious that if roses had resulted, it could only be because among the plants they allowed to remain there existed a rose-making quality of some kind, to which, and not to anything done by human art or skill, the result was due. It would likewise have to be supposed that there were infinite other potentialities latent in the original plants, as of evolving thistles, shamrocks, or leeks--all equally awaiting their opportunity. Selective action could effectually put such compet.i.tors out of the way; but in the way of developing a race it could but leave it entirely to itself.

Precisely similar is the part played by Natural Selection, except that it must needs play it immensely more slowly,--and if no one can fancy that human agency could by any possibility grow roses unless from some stock predetermined to grow into a rose and nothing else, what grounds have we that can be called scientific for attributing to a blind struggle for life an incomparably greater potency? Nor does it avail to quote the immense extent of time which may be supposed to have been available. No more than Natural Selection has time by itself any creative power. We know on the contrary by experience, that when things are not controlled by some principle of order, the lapse of time serves only to make confusion worse confounded.

Another consideration of prime importance is too frequently ignored. On Darwinian principles, each step in any development can be made, not because it leads to an advantageous result in the future, but only because it is itself advantageous. At each stage favoured individuals survive others because they are favoured here and now, not because, when the development they promote shall be completed, their remote descendants will be favoured. Hence it must, for instance, be possible to suppose, that all the intermediate forms between two extremes, whereof one is supposed to have originated the other, were, each in its day, so beneficial as to preserve their possessors at the expense of non-possessors. But can this possibly be even imagined?

To take one example. We have heard, speaking of embryology, that the feet of lizards and the wings and feet of birds arise from the same fundamental form of limb, whence it is argued that birds and lizards are alike descended from a common sauroid, or lizard-like, ancestor, whose limbs in the case of the former cla.s.s have developed into wings and into feet of a totally new type,--while scales were developing into feathers, and innumerable alterations of internal structure were simultaneously in progress. But if so, to confine our attention to one particular, it must be true that each of the innumerable minute gradations between the fore-limb of a lizard and the wing of a bird, was in its turn the best kind of member for a creature to possess, giving him a distinct advantage in the struggle for existence. Nothing, however, appears plainer than that this could not possibly have been the case. The limb shaping towards a wing would be a very clumsy and inefficient leg long before it got to the point at which it became of the slightest use for purposes of flight, that is to say before its alteration was accompanied by any utility whatever. We can neither imagine that creatures furnished with limbs of such intermediate forms could have been otherwise than hopelessly handicapped by them, nor do we find anywhere in the rocks any trace whatever of the innumerable series of modifications which would be needed to link by imperceptible gradations legs and wings together.

It only serves to make the matter less intelligible, that there _are_ found in Secondary strata some few relics of birds with decidedly saurian characteristics,[198] as the _Hesperornis_ and _Ichthyornis_ in the Chalk, and the _Archaeopteryx_, most ancient of fowls, lower still, in the Oolite. All these creatures have lizard-like heads and teeth; the _Archaeopteryx_ in addition has decidedly reptilian characters connected with its wings and tail. But none of them throw the slightest light upon the point we are now considering. In the case of all, the problem of flight has been completely solved. Their wings are no rudimentary structures half way between legs and wings, but as finished productions as those of to-day. As Professor Huxley acknowledges, if the skeletons of _Hesperornis_ and _Icthyornis_ had been found without their skulls, they would probably have been cla.s.sed without more ado amongst existing birds. The latter "has, [he tells us,] strong wings, and no doubt possessed corresponding powers of flight." The wings of _Hesperornis_, he says, resemble those of our divers and grebes, and were probably used, like theirs, chiefly for swimming.[199] As for the _Archaeopteryx_, its reptilian features notwithstanding, it is a perfectly-appointed bird. As Sir Richard Owen testifies,[200] its wing, despite the peculiarities mentioned, is completely developed as to all essentials.

Nor does even this member furnish the creature with its most bird-like characteristics,--but the keeled breast-bone, so intimately connected with the requirements of flight,--and, still more markedly, the feet.

Professor Huxley writes: "The feet are not only altogether bird-like, but have the special character of the feet of perching birds; while the body had a clothing of true feathers."

Thus, to whatever these Saurian birds may testify,--and the extreme importance of their evidence none will question--they no more serve to bridge the gulf between reptiles and birds, than a group of volcanic islets like the Azores bridges the Atlantic, for they supply no vestige of a continuous way from one term to the other. Rather, they do but enhance the mystery of the transformation, to the manner of which, despite their composite features, they furnish no clue.

All such difficulties are enormously aggravated by a consideration which, obvious as it is, seems seldom to be considered. The arguments we commonly hear appear to imply that _one_ parent is sufficient to secure the transmission of a beneficial variation to the next generation. But, of course, the parent requires a mate, and unless this mate has chanced to hit on the same line of variation, it cannot be supposed that it will be transmitted. Seeing, however, the exceeding minuteness of these variations in each instance, they can avail nothing to bring together the right mates to perpetuate them. Two reptiles, for instance, are not the more likely to pair because their fore limbs have taken the first faint and distant step towards becoming wings, while in the vegetable kingdom, notwithstanding Erasmus Darwin's _Loves of the Plants_, the idea of any choice of partners is still more grotesque. The allotment of mates must therefore be left to Chance; and the results will follow the ordinary laws of probability. Accordingly, if we suppose so large a proportion as five per cent., or one in twenty, of any species to possess an advantageous variation,--only one in twenty of the individuals thus favoured will secure a similarly favoured mate,--for each will have nineteen wrong selections offered to him or her, for one right one. Only one pair in four hundred will therefore transmit the variation to five per cent. of _their_ offspring, or one in eight thousand of the species, and of these only one pair in a-hundred-and-sixty-thousand will make an advantageous match. Such is the inevitable consequence of leaving any definite result to Chance: and here it is that Natural Selection is found to betray the most fatal of all its deficiencies; for, whatever its advocates may say, it is Chance and Chance alone upon which it relies. Just because man can and does select the proper mates, is he able to produce by breeding the results to which Mr. Darwin appeals as evidence, that Nature having no such power of selection, must be able to produce results of which man cannot even dream.[201]

Natural Selection is in truth no selection at all, that is just its weak point, which the t.i.tle conferred upon it serves to hide. What are called its products owe no more to it than Wellington owed his generals.h.i.+p to the bullets which did not hit him at Seringapatam. If they are not determined to a particular development they can attain it only by Chance.

Of Chance, enough has already been said. It is, however, worth our while to observe how constantly to the last Mr. Darwin was haunted by the consciousness that this was in reality the factor upon which his system must depend, and that it could not possibly account for much that he came across in nature. If, as he confessed, the sight of a peac.o.c.k's tail-feather made him sick, it was just because its elaborate beauty, to which no commensurate advantage can be supposed to attach, forbade the notion that his theory could account for it. So, of another still more marvellous instance in which Nature exhibits artistic power, namely the ball-and-socket ornament on the wings of the Argus pheasant, he writes:[202]

No one, I presume, will attribute this shading, which has excited the admiration of many experienced artists, to chance--to the fortuitous concourse of atoms of colouring matter. That these ornaments should have been formed through the selection of many successive variations, not one of which was originally intended to produce the ball-and-socket effect, seems as incredible as that one of Raphael's Madonnas should have been formed by the selection of chance daubs of paints made by a long succession of young artists, not one of whom intended at first to draw the human figure.

[Ill.u.s.tration:

1. Basal portion of secondary wing-feather; nearest body, shewing first rudiment of "ocelli."

2. Portion of secondary wing-feather near body, shewing "elliptic"

ornaments.

3. Part of secondary wing-feather, shewing developed "ocelli."

Feathers from wing of Argus Pheasant, from Darwin's _Descent of Man_.]

Nevertheless, Mr. Darwin proceeds to argue at considerable length that an explanation consistent with his theory is favoured by the occurrence on the same wings of designs exhibiting every stage of gradation from a mere spot to the finished ball-and-socket _ocellus_; in the same way as the tail feathers of a peac.o.c.k advance from a mere sketch to the completed design. It is not easy, however, to understand in what way this is supposed to solve the difficulty and not vastly to increase it.

That a finished artistic effect should be fortuitously produced at all would be incredible enough. That it should be worked up by Chance through a series of processes, each doing something towards its completion, is surely not less, but far more inconceivable.

In such a mode of explanation, however, is exemplified a feature which must not be forgotten in discussing Darwinism,--namely the fatal facility with which seeming arguments can be procured on its behalf. As Mr. Mivart well remarks:[203] "The Darwinian theory has the great advantage of only needing for its support the suggestion of some possible utility, actual or ancestral, in each case--no difficult task for an ingenious, patient, and accomplished thinker." And our _North British_ Reviewer makes a similar comment: "The believer who is at liberty to invent any imaginary circ.u.mstances, will very generally be able to conceive some series of trans.m.u.tations answering his wants."

Or if, as in the above instance of the Argus' eyes, a series is actually found, it is even less difficult to take for granted that it can have but one significance; while such a.s.sumptions are too frequently accepted without hesitation or demur, although it would be no easy task to show that they rest upon any solid grounds. When, in addition, either Mr. Darwin himself or some of his leading partisans has declared that some unverified process has undoubtedly occurred, or that they see no reason to doubt its occurrence, or that nothing which we know precludes its possibility,--it appears to be widely supposed that something substantial is thereby added to the scientific evidence, and that the suppositions thus sanctioned may even rank as facts. But however such a method may avail to secure acceptance for a doctrine, it does nothing for its scientific value. Such a style, as Mr. Mivart says,[204] is calculated to impress only minds too easily dominated, and not prepared by special studies accurately to weigh the evidence put before them.

Ill.u.s.trations of this strange method of procedure are furnished in connexion with various points already mentioned. Thus, as we have seen, Mr. Darwin attempts to explain the origin of rational speech, by the conscious utterance of a significant sound by an unusually wise ape-like creature. In favour of this very large suggestion, Mr. Darwin has nothing more substantial to say[205] than that "it does not appear altogether incredible," which does not appear to take us very far.[206]

Yet I have seen this described as an "idyllic scene" shedding an entirely new light on the subject. So again in regard of the evolution of the eye.[207] Having summarily enumerated the various stages of development exhibited by this organ as actually existing in various animals, Mr. Darwin goes on to say that when we remember how small the number of living forms must be in comparison with extinct, and the other gradations that may consequently have existed, "the difficulty ceases to be very great" in believing that Natural Selection has connected the most rudimentary with the perfect structure. Similarly, as to the cell-making instinct of the bee,[208] having postulated four several suppositions for which evidence is not forthcoming, he concludes: "By such modification of instincts ... I believe that the hive bee has acquired, through natural selection, her inimitable architectural powers."[209] Similar examples might be multiplied indefinitely.

Not unfrequently the tone of such utterances is more imperious. Thus, of the descent of Man from some animal ancestor Mr. Darwin p.r.o.nounces[210]

"The grounds upon which this conclusion rests will never be shaken," and again[211] "the possession of exalted mental powers is no insuperable objection to this conclusion" ... "It is only [p. 32] our natural prejudice which leads us to demur to this conclusion." He even goes so far as to declare that his view is forced upon every man who is not content to a.s.sume the mental att.i.tude of a savage.[212]

Argumentation of this character, which he finds common with Darwin to other Evolutionists, is judged by de Quatref.a.ges to be one of the weakest and most misleading features of their systems.

Personal conviction [he writes],[213] mere possibility, are offered as proofs, or at least as arguments in favour of the theory. Can we admit their validity? Obviously not. The human mind can conceive many things: is that a reason for accepting them all?... Obviously more serious proofs are needed. After all, save where a contradiction is involved, everything is _possible_.... If adopting, under the shadow of Oken's great name, his principle of the repet.i.tion of phenomena, a naturalist should maintain that each of the planets has its own Europe, its England, and its Darwin expounding to the Jovians and Saturnians the origin of species, I do not quite see how one would set about showing him that he was wrong. Unquestionably the thing is _possible_. Are we to draw the conclusion that it is a fact?

Again,[214] the same distinguished naturalist, having quoted Darwin's very elaborate explanation of a difficulty, remarks: We see how with Darwin, as with his precursors, one hypothesis necessitates another. But can he, at least, by means of these subsidiary theories, these comparisons, these metaphors, account for all the facts? No, he himself honestly confesses more than once that he cannot. It is true that he adds "I am convinced that the objections have little weight, and the difficulties are not insoluble." But is this conviction of his a proof, or even an argument?

M. Blanchard likewise comments vigorously on this mode of argumentation.

Speaking of the Mole and Darwin's explanation of its blindness, namely that having taken to living under-ground it lost its eyes through disuse--which he considers a most preposterous supposition,--M Blanchard continues:[215]

The realms of fancy are boundless; but the observer who is concerned with realities can only have recourse to the facts of science. Fossil remains discovered in very ancient strata show that the underground animal of present times does not differ from his geological counterpart. The Mole belongs to a very peculiar type, and has no nearer European relatives than the Hedgehog and the Shrew. Can we imagine a common ancestor of Shrews, Hedgehogs, and Moles? On this point Mr. Darwin expresses no opinion,--which should not be, for when confronted by forms clearly differentiated, he is wont to extricate himself from difficulties with matchless facility. The intermediate links, he will say, were doubtless less fitted to live than were the others, and so have disappeared. After _that_ the Evolutionists consider any one quite out of date who does not consider himself entirely satisfied with so felicitous an explanation.

M. de Quatref.a.ges denounces another fatal defect often observable in the method of proof.

Mr. Darwin frequently complains that our actual knowledge is incomplete. But instead of discovering in our lack of precise and extensive information a motive for caution, he appears to derive from it only greater daring. Doctrines based on the instability of species have often been combated by geologists and palaeontologists.

In reply to their objections Darwin devotes a whole chapter to shewing the imperfection of the geological record. "For my part,"

he concludes, "I look at the geological record as a history of the world imperfectly kept and written in a changing dialect; of this history we possess the last volume alone, relating only to two or three countries. Of this volume, only here and there a short chapter has been preserved; and of each page, only here and there a few lines. Each word of the slowly-changing language, more or less different in the successive chapters, may represent the forms of life, which are entombed in our consecutive formations, and which falsely appear to have been abruptly introduced. On this view, the difficulties above discussed are greatly diminished, or even disappear."

On my part [continues M. de Quatref.a.ges] I will ask whether such a conclusion is the correct one. No doubt, Darwin is right in refusing to certain naturalists the right to dogmatize on the strength of uncompleted studies, or scanty and isolated observations. Is he therefore ent.i.tled to allege as proofs on his own behalf the very gaps of science, appealing to the lost volumes and leaves of Nature's chronicle? Clearly not. But the slightest reflection suffices to recognize that this appeal to the unknown, so frankly evidenced in the above pa.s.sage, lies at the root of all argumentation a.n.a.logous to that which I have tried to describe--that of Maillet, Lamarck, and Geoffroy,[216] as well as Darwin. Only the unknown, in sooth, can open the boundless region of speculation, where the possible replaces the actual, and where, despite the widest knowledge and the soundest intelligence, one comes as by a fatality to find a conclusive proof on one's own side, precisely in that of which we profess to know nothing.