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natural, but with Mr Darwin, whose whole system is aimed against the idea of creation, nothing can be more inappropriate—nothing more self-convicting. It is the result of an habitual abuse of words. The learned author of the system has so continually spoken of Natural Selection, as a real existence, and an Intelligent Power in Nature, that he has at last, in his moments of inattention, come to think that the phantasy is indeed a real substance, and he has, in consequence, made use of expressions which stultify all his Theory. If the arrangements of which he speaks were not accidental, they certainly were intentional, they were the result of a design, they were, as he says, a singular case of adaptation, and were devised and planned to produce the effect which he so much admires.
All this is true, but then it annihilates the Theory.
Wherever we turn in our inspection of this Theory we find that ingenuity has been taxed to produce imaginary beings, events, and circumstances, which have no existence but in the magisterial affirmation of the inventor; and that the whole system from beginning to end is based on assumption without proof. Every step of the argument is wanting in that exact evidence which Science demands even in the most ordinary case, but which in a Theory such as this would require more than usual scrutiny. We have a profusion of physiological learning, abstract reasoning, and ingenious speculations, but the plain direct facts which are indispensable for establishing the main points are wanting. Probabilities and possibilities abound, and it is a favourite expression with the learned author that ' he sees no great difficulty in believing' some strange proposition adduced in the course of his argument. We have analogies and presumptions, and all the expedients of able special pleading—we have questionable propositions taken for principles, but the evidence which should establish them wholly omitted; and we meet with the freest flights of the imagination in asserting circumstances as facts, which have no more claim to our credence than the mythical allegories of the Hindoo Cosmogony.
Locke, in his 20th chapter, on the Causes of Error, has placed amongst the first, want of proofs ; and these pages will have shown the reader that the instances are numerous in which we have met with assertions unsupported by proof.
Let us now in recapitulation look at a few of the most striking instances.
In the matter of species, the primum mobile of the Theory, Mr Darwin acknowledges that his scheme is an assumption. He tells us that varieties in process of time become species, then, after a long interval, they vary again, and so ultimately make another species.
That varieties more or less different from the parent stock occasionally arise, few will deny, that the process of variation should be thus indefinitely prolonged (i.e. that they should become species) is an assumption, the truth of which must be judged of by how far the hypothesis accords with and explains the general phenomena of Na. ture' (89).
Now this process of variations becoming what Mr Dar. win calls “good species,' is an assumption for an hypothesis. This we learn from the best authority; and this be it remembered is the great point of the Theory, the Mutability of Species.
Again, we hear that 'new forms are continually and
slowly being produced’ (115). What evidence has Mr Darwin for this assertion ? where are his proofs ? the answer is that historical time is as nothing for such a process ; five or six thousand years, the utmost reach of history, are a trifle for Natural Selection. The slowness is that of geological time. Be it so, but still the process is an assertion without a proof.
Again : 'As new forms are continually and slowly being produced, unless we believe that the number of specific forms goes on perpetually and almost indefinitely increasing, numbers must inevitably become extinct. That the number of specific forms has not indefinitely increased geology* tells us plainly' (89).
This, as a specimen of Mr Darwin's reasoning, deserves more than passing attention.
First he lays it down as an established fact—as an axiom —that new forms are continually and slowly being produced,' and then, on this assertion, the logic of the rest of the sentence is constructed.
New forms are continually being produced.
Therefore the new forins are exterminated.-Q. E. D. Again : varieties are frequently called “incipient species ;' an assertion without proof (131).
Here again geology is admitted as an unanswerable witness whose testimony must settle the question : and that on the very point of the greatest importance to Mr Darwin. It is a question of the indefinite increase of specific forms. The evidence which geology offers on this question is here taken as decisive: but when we ask for the evidence of his exterininated intermediate forms in the records of geology, he tells us that the extreme imperfection of the record fails in proving that on which his theory depends. Thus geology is good evidence against the indefinite increase of forms, because it does not produce them ; but for the extermination of an indefinite number of forms it is a bad witness for the same reason, because it does not produce them.
Again : 'When a part has been developed in an extraordinary manner in any one species, compared with the other species of the same genus, we may conclude that the part has undergone an extraordinary amount of modification since the period when the species branched off from the common progenitor of the genus' (171).
Here are three assumptions: 1. That parts of organizations have undergone modification. 2. That the species branched off. 3. That there is a common progenitor of a genus. No proof is offered for any of these propositions.
Again: the retrogression of animals, and their degradation into a lower form, is entirely hypothetical. There is no proof of this in nature, and Mr Darwin offers nothing to confirm it but his simple assertion.
All the particular cases of metamorphose, as a bustard into an ostrich, a tapir into a horse, &c., &c., are purely visionary. No proof of these pretended changes is mentioned.
The account of the formation of the eye-of the tails of animals—of the beautiful plumage of birds, and other parts of animal organization, is in every instance given to us without an attempt at proof.
The gradual advance of organized beings towards perfection is visionary, proof indeed could not be given of such a prediction.
The assertion that the animals of lower form have not been advanced to the higher, because it would not be for their benefit, as it is altogether visionary, and incapable of proof, has been propounded merely to parry an unanswerable argument against the Theory.
The doctrine of Natural Selection by extermination is an assertion without proof. It is, however, disproved by the testimony of geology, and this Mr Darwin acknowledges to be a most serious difficulty. We ask for the intermediate forms swept off by millions through Natural Selection. Where are they to be found? And why not found when so many forms of distinct organization have been discovered in all parts of the world ? All the distinct forms, or great numbers of them, have been discovered, but the intermediates are as if they had never existedthey are invisible.* And an Edinburgh Reviewer has well said 'that Geology, not seen through the mist of any theory, but taken as a plain succession of monuments and facts, offers one firm cumulative argument against the hypothesis.'
Finally, the pretended origin of all plants and animals from one primordial form-a spore of one of the lowest algæ, is visionary. No proof can be adduced of such a proposition, which surely may bear the palm amongst preposterous conjectures.
Thus all the main parts of the Theory are assertions without proof. It is not a system established by inductive reasoning, but by conjecture, assumption, and invention. Now all natural knowledge is based on inductive reasoning. We have learnt to comprehend the mechanical movement of the heavens by first learning the laws of motion upon the earth. In like manner we have learnt to speculate securely on the functions of organized beings during the old conditions of the earth, by first studying the laws of organic life among the phenomena of living nature. In every instance we must begin with what is known and
Cependant on peut leur repondre, dans leur propre systême, que si les espèces ont changé par degrés, on devroit trouver des traces de ces modifications graduelles ;- pourquoi les entrailles de la terre n'ont elles point conservé les monuments d'une généalogie si curieuse.'-Cuvier, Discours Preliminaire (74).