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[24] 'Nat. Theol.,' ch. xxiii.

[25] 'Oiseaux,' vol. i. p. 5.

[26] 'Westminster Review,' vol. xlix. p. 124.

[27] Translation: "The first of these two attempts is a true 'philosophy of the unconscious,' not Hartmann's unconscious, which influences the natural evolution of organism from without as though by Providence and miracle, but of an unconscious, which, as the author shows, our own experience and the progressive succession of organisms from the monads and amœbæ up to the highest plants and animals, including ourselves, allows, if it does not compel us to assume [as obtaining] in all organic beings. This philosophy of the unconscious is new, or at any rate now for the first time carried out consequentially in detail; its main features, briefly stated are as follows."

CHAPTER VI.

SCHEME OF THE REMAINDER OF THE WORK. HISTORICAL SKETCH OF THE THEORY OF EVOLUTION.

I have long felt that evolution must stand or fall according as it is made to rest or not on principles which shall give a definite purpose and direction to the variations whose accumulation results in specific, and ultimately in generic differences. In other words, according as it is made to stand upon the ground first clearly marked out for it by Dr. Erasmus Darwin and afterwards adopted by Lamarck, or on that taken by Mr. Charles Darwin.

There is some reason to fear that in consequence of the disfavour into which modern Darwinism is seen to be falling by those who are more closely watching the course of opinion upon this subject, evolution itself may be for a time discredited as something inseparable from the theory that it has come about mainly through "the means" of natural selection. If people are shown that the arguments by which a somewhat startling conclusion has been reached will not legitimately lead to that conclusion, they are very ready to assume that the conclusion must be altogether unfounded, especially when, as in the present case, there is a vast mass of vested interests opposed to the conclusion. Few know that there are other great works upon descent with modification besides Mr. Darwin's. Not one person in ten thousand has any distinct idea of what Buffon, Dr. Darwin, and Lamarck propounded. Their names have been discredited by the very authors who have been most indebted to them; there is hardly a writer on evolution who does not think it incumbent upon him to warn Lamarck off the ground which he at any rate made his own, and to cast a stone at what he will call the "shallow speculations" or "crude theories" or the "well-known doctrine" of the foremost exponent of Buffon and Dr. Darwin. Buffon is a great name, Dr. Darwin is no longer even this, and Lamarck has been so systematically laughed at that it amounts to little less than philosophical suicide for anyone to stand up in his behalf. Not one of our scientific elders or chief priests but would caution a student rather to avoid the three great men whom I have named than to consult them. It is a perilous task therefore to try and take evolution from the pedestal on which it now appears to stand so securely, and to put it back upon the one raised for it by its propounders; yet this is what I believe will have to be done sooner or later unless the now general acceptance of evolution is to be shaken more rudely than some of its upholders may anticipate. I propose therefore to give a short biographical sketch of the three writers whose works form new departures in the history of evolution, with a somewhat full résumé of the positions they took in regard to it. I will also touch briefly upon some other writers who have handled the same subject. The reader will thus be enabled to follow the development of a great conception as it has grown up in the minds of successive men of genius, and by thus growing with it, as it were, through its embryonic stages, he will make himself more thoroughly master of it in all its bearings.

I will then contrast the older with the newer Darwinism, and will show why the 'Origin of Species,' though an episode of incalculable value, cannot, any more than the 'Vestiges of Creation,' take permanent rank in the literature of evolution.

It will appear that the evolution of evolution has gone through the following principal stages:—

I. A general conception of the fact that specific types were not always immutable.

This was common to many writers, both ancient and modern; it has been occasionally asserted from the times of Anaximander and Lucretius to those of Bacon and Sir Walter Raleigh.

II. A definite conception that animal and vegetable forms were so extensively mutable that few (and, if so, perhaps but one) could claim to be of an original stock; the direct effect of changed conditions being assigned as the cause of modification, and the important consequences of the struggle for existence being in many respects fully recognized. The fact of design or purpose in connection with organism, as causing habits and thus as underlying all variation, was also indicated with some clearness, but was not thoroughly understood.

This phase must be identified with the name of Buffon, who, as I will show reason for believing, would have carried his theory much further if he had not felt that he had gone as far in the right direction as was then desirable. Buffon put forward his opinions, with great reserve and yet with hardly less frankness, in volume after volume from 1749 to 1788, the year of his death, but they do not appear to have taken root at once in France. They took root in England, and were thence transplanted back to France.

III. A development in England of the Buffonian system, marked by glimpses of the unity between offspring and parents, and broad suggestions to the effect that the former must be considered as capable of remembering, under certain circumstances, what had happened to it, and what it did, when it was part of the personality of those from whom it had descended.

A definite belief, openly expressed, that not only are many species mutable, but that all living forms, whether animal or vegetable, are descended from a single, or at any rate from not many, original low forms of life, and this as the direct consequence of the actions and requirements of the living forms themselves, and as the indirect consequence of changed conditions. A definite cause is thus supposed to underlie variations, and the resulting adaptations become purposive; but this was not said, nor, I am afraid, seen.

This is the original Darwinism of Dr. Erasmus Darwin. It was put forward in his 'Zoonomia,' in 1794, and was adopted almost in its entirety by Lamarck, who, when he had caught the leading idea (probably through a French translation of the 'Loves of the Plants,' which appeared in 1800), began to expound it in 1801; in 1802, 1803, 1806, and 1809, he developed it with greater fulness of detail than Dr. Darwin had done, but perhaps with a somewhat less nice sense of some important points. Till his death, in 1831, Lamarck, as far as age and blindness would permit, continued to devote himself to the exposition of the theory of descent with modification.

IV. A more distinct perception of the unity of parents and offspring, with a bolder reference of the facts of heredity (whether of structure or instinct), to memory pure and simple; a clearer perception of the consequences that follow from the survival of the fittest, and a just view of the relation in which those consequences stand to "the circumstance-suiting" power of animals and plants; a reference of the variations whose accumulation results in species, to the volition of the animal or plant which varies, and perhaps a dawning perception that all adaptations of structure to need must therefore be considered as "purposive."

This must be connected with Mr. Matthew's work on 'Naval Timber and Arboriculture,' which appeared in 1831. The remarks which it contains in reference to evolution are confined to an appendix, but when brought together, as by Mr. Matthew himself, in the 'Gardeners' Chronicle' for April 7, 1860, they form one of the most perfect yet succinct expositions of the theory of evolution that I have ever seen. I shall therefore give them in full.[28] This book was well received, and was reviewed in the 'Quarterly Review,'[29] but seems to have been valued rather for its views on naval timber than on evolution. Mr. Matthew's merit lies in a just appreciation of the importance of each one of the principal ideas which must be present in combination before we can have a correct conception of evolution, and of their bearings upon one another. In his scheme of evolution I find each part kept in due subordination to the others, so that the whole theory becomes more coherent and better articulated than I have elsewhere found it; but I do not detect any important addition to the ideas which Dr. Darwin and Lamarck had insisted upon.

I pass over the 'Vestiges of Creation,' which should be mentioned only as having, as Mr. Charles Darwin truly says, "done excellent service in this country, in calling attention to this subject, in removing prejudice, and in thus preparing the ground for the reception of analogous views."[30] The work neither made any addition to ideas which had been long familiar, nor arranged old ones in a satisfactory manner. Such as it is, it is Dr. Darwin and Lamarck, but Dr. Darwin and Lamarck spoiled. The first edition appeared in 1844.

I also pass over Isidore Geoffroy St. Hilaire's 'Natural History,' which appeared 1854–62, and the position of which is best described by calling it intermediate between the one which Buffon thought fit to pretend to take, and that actually taken by Lamarck. The same may be said also of Étienne Geoffroy. I will, however, just touch upon these writers later on.

A short notice, again, will suffice for the opinions of Goethe, Treviranus, and Oken, none of whom can I discover as having originated any important new idea; but knowing no German, I have taken this opinion from the résumé of each of these writers, given by Professor Haeckel in his 'History of Creation.'

V. A time of retrogression, during which we find but little apparent appreciation of the unity between parents and offspring; no reference to memory in connection with heredity, whether of instinct or structure; an exaggerated view of the consequences which may be deduced from the fact that the fittest commonly survive in the struggle for existence; the denial of any known principle as underlying variations; comparatively little appreciation of the circumstance-suiting power of plants and animals, and a rejection of purposiveness. By far the most important exponent of this phase of opinion concerning evolution is Mr. Charles Darwin, to whom, however, we are more deeply indebted than to any other living writer for the general acceptance of evolution in one shape or another. The 'Origin of Species' appeared in 1859, the same year, that is to say, as the second volume of Isidore Geoffroy's 'Histoire Naturelle Générale.'

VI. A reaction against modern Darwinism, with a demand for definite purpose and design as underlying variations. The best known writers who have taken this line are the Rev. J. J. Murphy and Professor Mivart, whose 'Habit and intelligence' and 'Genesis of Species' appeared in 1869 and 1871 respectively. In Germany Professor Hering has revived the idea of memory as explaining the phenomena of heredity satisfactorily, without probably having been more aware that it had been advanced already than I was myself when I put it forward recently in 'Life and Habit.' I have never seen the lecture in which Professor Hering has referred the phenomena of heredity to memory, but will give an extract from it which appeared in the 'Athenæum,' as translated by Professor Ray Lankester.[31] The only new feature which I believe I may claim to have added to received ideas concerning evolution, is a perception of the fact that the unconsciousness with which we go through our embryonic and infantile stages, and with which we discharge the greater number and more important of our natural functions, is of a piece with what we observe concerning all habitual actions, as well as concerning memory; an explanation of the phenomena of old age; and of the main principle which underlies longevity. I may, perhaps, claim also to have more fully explained the passage of reason into instinct than I yet know of its having been explained elsewhere.[32]