Charles Darwin: His Life in an Autobiographical Chapter Part 19

[123] In 1860 he wrote to Lyell: "Is not Krohn a good fellow? I have long meant to write to him. He has been working at Cirripedes, and has detected two or three gigantic blunders, about which, I thank Heaven, I spoke rather doubtfully. Such difficult dissection that even Huxley failed. It is chiefly the interpretation which I put on parts that is so wrong, and not the parts which I describe. But they were gigantic blunders, and why I say all this is because Krohn, instead of crowing at all, pointed out my errors with the utmost gentleness and pleasantness."

There are two papers by Aug. Krohn, one on the Cement Glands, and the other on the development of Cirripedes, _Weigmann's Archiv._ xxv. and xxvi. See _Autobiography_, p. 39, where my father remarks, "I blundered dreadfully about the cement glands."

[124] The duplicate type-specimens of my father's Cirripedes are in the Liverpool Free Public Museum, as I learn from the Rev. H. H. Higgins.

CHAPTER IX.

THE FOUNDATIONS OF THE 'ORIGIN OF SPECIES.'

To give an account of the development of the chief work of my father's life--the _Origin of Species_, it will be necessary to return to an earlier date, and to weave into the story letters and other material, purposely omitted from the chapters dealing with the voyage and with his life at Down.

To be able to estimate the greatness of the work, we must know something of the state of knowledge on the species question at the time when the germs of the Darwinian theory were forming in my father's mind.

For the brief sketch which I can here insert, I am largely indebted to vol. ii. chapter v. of the _Life and Letters_--a discussion on the _Reception of the Origin of Species_ which Mr. Huxley "was good enough to write for me, also to the masterly obituary essay on my father, which the same writer contributed to the Proceedings of the Royal Society."[125]

Mr. Huxley has well said[126]:

"To any one who studies the signs of the times, the emergence of the philosophy of Evolution, in the att.i.tude of claimant to the throne of the world of thought, from the limbo of hated and, as many hoped, forgotten things, is the most portentous event of the nineteenth century."

In the autobiographical chapter, my father has given an account of his share in this great work: the present chapter does little more than expand that story.

Two questions naturally occur to one: (1)--When and how did Darwin become convinced that species are mutable? How (that is to say) did he begin to believe in evolution. And (2)--When and how did he conceive the manner in which species are modified; when did he begin to believe in Natural Selection?

The first question is the more difficult of the two to answer. He has said in the _Autobiography_ (p. 39) that certain facts observed by him in South America seemed to be explicable only on the "supposition that species gradually become modified." He goes on to say that the subject "haunted him"; and I think it is especially worthy of note that this "haunting,"--this unsatisfied dwelling on the subject was connected with the desire to explain _how_ species can be modified. It was characteristic of him to feel, as he did, that it was "almost useless"

to endeavour to prove the general truth of evolution, unless the cause of change could be discovered. I think that throughout his life the questions 1 and 2 were intimately,--perhaps unduly so, connected in his mind. It will be shown, however, that after the publication of the _Origin_, when his views were being weighed in the balance of scientific opinion, it was to the acceptance of Evolution not of Natural Selection that he attached importance.

An interesting letter (Feb. 24, 1877) to Dr. Otto Zacharias,[127] gives the same impression as the _Autobiography_:--

"When I was on board the _Beagle_ I believed in the permanence of species, but as far as I can remember, vague doubts occasionally flitted across my mind. On my return home in the autumn of 1836, I immediately began to prepare my Journal for publication, and then saw how many facts indicated the common descent of species, so that in July, 1837, I opened a note-book to record any facts which might bear on the question. But I did not become convinced that species were mutable until, I think, two or three years had elapsed."

Two years bring us to 1839, at which date the idea of natural selection had already occurred to him--a fact which agrees with what has been said above. How far the idea that evolution is conceivable came to him from earlier writers it is not possible to say. He has recorded in the _Autobiography_ (p. 38) the "silent astonishment with which, about the year 1825, he heard Grant expound the Lamarckian philosophy." He goes on:--

"I had previously read the _Zoonomia_ of my grandfather, in which similar views are maintained, but without producing any effect on me.

Nevertheless, it is probable that the hearing rather early in life such views maintained and praised, may have favoured my upholding them under a different form in my _Origin of Species_. At this time I admired greatly the _Zoonomia_; but on reading it a second time after an interval of ten or fifteen years, I was much disappointed; the proportion of speculation being so large to the facts given."

Mr. Huxley has well said (Obituary Notice, p. ii.): "Erasmus Darwin, was in fact an antic.i.p.ator of Lamarck, and not of Charles Darwin; there is no trace in his works of the conception by the addition of which his grandson metamorphosed the theory of evolution as applied to living things, and gave it a new foundation."

On the whole it seems to me that the effect on his mind of the earlier evolutionists was inappreciable, and as far as concerns the history of the _Origin of the Species_, it is of no particular importance, because, as before said, evolution made no progress in his mind until the cause of modification was conceivable.

I think Mr. Huxley is right in saying[128] that "it is hardly too much to say that Darwin's greatest work is the outcome of the unflinching application to biology of the leading idea, and the method applied in the _Principles_ to Geology." Mr. Huxley has elsewhere[129] admirably expressed the bearing of Lyell's work in this connection:--

"I cannot but believe that Lyell, for others, as for myself, was the chief agent in smoothing the road for Darwin. For consistent uniformitarianism postulates evolution as much in the organic as in the inorganic world. The origin of a new species by other than ordinary agencies would be a vastly greater 'catastrophe' than any of those which Lyell successfully eliminated from sober geological speculation....

"Lyell,[130] with perfect right, claims this position for himself. He speaks of having 'advocated a law of continuity even in the organic world, so far as possible without adopting Lamarck's theory of trans.m.u.tation....

"'But while I taught,' Lyell goes on, 'that as often as certain forms of animals and plants disappeared, for reasons quite intelligible to us, others took their place by virtue of a causation which was beyond our comprehension; it remained for Darwin to acc.u.mulate proof that there is no break between the incoming and the outgoing species, that they are the work of evolution, and not of special creation.... I had certainly prepared the way in this country, in six editions of my work before the _Vestiges of Creation_ appeared in 1842 [1844], for the reception of Darwin's gradual and insensible evolution of species.'"

Mr. Huxley continues:--

"If one reads any of the earlier editions of the _Principles_ carefully (especially by the light of the interesting series of letters recently published by Sir Charles Lyell's biographer), it is easy to see that, with all his energetic opposition to Lamarck, on the one hand, and to the ideal quasi-progressionism of Aga.s.siz, on the other, Lyell, in his own mind, was strongly disposed to account for the origination of all past and present species of living things by natural causes. But he would have liked, at the same time, to keep the name of creation for a natural process which he imagined to be incomprehensible."

The pa.s.sage above given refers to the influence of Lyell in preparing men's minds for belief in the _Origin_, but I cannot doubt that it "smoothed the way" for the author of that work in his early searchings, as well as for his followers. My father spoke prophetically when he wrote the dedication to Lyell of the second edition of the _Journal of Researches_ (1845).

"To Charles Lyell, Esq., F.R.S., this second edition is dedicated with grateful pleasure--as an acknowledgment that the chief part of whatever scientific merit this journal and the other works of the author may possess, has been derived from studying the well-known and admirable _Principles of Geology_."

Professor Judd, in some reminiscences of my father which he was so good as to give me, quotes him as saying that, "It was the reading of the _Principles of Geology_ which did most towards moulding his mind and causing him to take up the line of investigation to which his life was devoted."

The _role_ that Lyell played as a pioneer makes his own point of view as to evolution all the more remarkable. As the late H. C. Watson wrote to my father (December 21, 1859):--

Now these novel views are brought fairly before the scientific public, it seems truly remarkable how so many of them could have failed to see their right road sooner. How could Sir C. Lyell, for instance, for thirty years read, write, and think, on the subject of species _and their succession_, and yet constantly look down the wrong road!

"A quarter of a century ago, you and I must have been in something like the same state of mind on the main question. But you were able to see and work out the _quo modo_ of the succession, the all-important thing, while I failed to grasp it."

In his earlier att.i.tude towards evolution, my father was on a par with his contemporaries. He wrote in the _Autobiography_:--

"I occasionally sounded not a few naturalists, and never happened to come across a single one who seemed to doubt about the permanence of species:" and it will be made abundantly clear by his letters that in supporting the opposite view he felt himself a terrible heretic.

Mr. Huxley[131] writes in the same sense:--

"Within the ranks of biologists, at that time [1851-58], I met with n.o.body, except Dr. Grant, of University College, who had a word to say for Evolution--and his advocacy was not calculated to advance the cause.

Outside these ranks, the only person known to me whose knowledge and capacity compelled respect, and who was, at the same time, a thorough-going evolutionist, was Mr. Herbert Spencer, whose acquaintance I made, I think, in 1852, and then entered into the bonds of a friends.h.i.+p which, I am happy to think, has known no interruption. Many and prolonged were the battles we fought on this topic. But even my friend's rare dialectic skill and copiousness of apt ill.u.s.tration could not drive me from my agnostic position. I took my stand upon two grounds: firstly, that up to that time, the evidence in favour of trans.m.u.tation was wholly insufficient; and, secondly, that no suggestion respecting the causes of the trans.m.u.tation a.s.sumed, which had been made, was in any way adequate to explain the phenomena. Looking back at the state of knowledge at that time, I really do not see that any other conclusion was justifiable."

These two last citations refer of course to a period much later than the time, 1836-37, at which the Darwinian theory was growing in my father's mind. The same thing is however true of earlier days.

So much for the general problem: the further question as to the growth of Darwin's theory of natural selection is a less complex one, and I need add but little to the history given in the _Autobiography_ of how he came by that great conception by the help of which he was able to revivify "the oldest of all philosophies--that of evolution."

The first point in the slow journey towards the _Origin of Species_ was the opening of that note-book of 1837 of which mention has been already made. The reader who is curious on the subject will find a series of citations from this most interesting note-book, in the _Life and Letters_, vol. ii. p. 5, _et seq._

The two following extracts show that he applied the theory of evolution to the "whole organic kingdom" from plants to man.

"If we choose to let conjecture run wild, then animals, our fellow brethren in pain, disease, death, suffering and famine--our slaves in the most laborious works, our companions in our amus.e.m.e.nts--they may partake [of] our origin in one common ancestor--we may be all melted together."

"The different intellects of man and animals not so great as between living things without thought (plants), and living things with thought (animals)."

Speaking of intermediate forms, he remarks:--

"Opponents will say--_show them me_. I will answer yes, if you will show me every step between bulldog and greyhound."

Here we see that the argument from domestic animals was already present in his mind as bearing on the production of natural species, an argument which he afterwards used with such signal force in the _Origin_.

A comparison of the two editions of the _Naturalists' Voyage_ is instructive, as giving some idea of the development of his views on evolution. It does not give us a true index of the ma.s.s of conjecture which was taking shape in his mind, but it shows us that he felt sure enough of the truth of his belief to allow a stronger tinge of evolution to appear in the second edition. He has mentioned in the _Autobiography_ (p. 40), that it was not until he read Malthus that he got a clear view of the potency of natural selection. This was in 1838--a year after he finished the first edition (it was not published until 1839), and seven years before the second edition was issued (1845). Thus the turning-point in the formation of his theory took place between the writing of the two editions. Yet the difference between the two editions is not very marked; it is another proof of the author's caution and self-restraint in the treatment of his ideas. After reading the second edition of the _Voyage_ we remember with a strong feeling of surprise how far advanced were his views when he wrote it.

These views are given in the ma.n.u.script volume of 1844, mentioned in the _Autobiography_. I give from my father's Pocket-book the entries referring to the preliminary sketch of this historic essay.

"_1842, May 18_,--Went to Maer. _June 15_--to Shrewsbury, and 18th to Capel Curig. During my stay at Maer and Shrewsbury ... wrote pencil sketch of species theory."[132]