LETTER 110. TO W.H. HARVEY.

LETTER 110. TO W.H. HARVEY.

(110/1. See Letter 95, note. This letter was written in reply to a long one from W.H. Harvey, dated August 24th, 1860. Harvey had already published a serio-comic squib and a review, to which references are given in the "Life and Letters," II., pages 314 and 375; but apparently he had not before this time completed the reading of the "Origin.")

[August, 1860.]

I have read your long letter with much interest, and I thank you for your great liberality in sending it me. But, on reflection, I do not wish to attempt answering any part, except to you privately. Anything said by myself in defence would have no weight; it is best to be defended by others, or not at all. Parts of your letter seem to me, if I may be permitted to say so, very acute and original, and I feel it a great compliment your giving up so much time to my book. But, on the whole, I am disappointed; not from your not concurring with me, for I never expected that, and, indeed, in your remarks on Chapters XII. and XIII., you go much further with me (though a little way) than I ever anticipated, and am much pleased at the result. But on the whole I am disappointed, because it seems to me that you do not understand what I mean by Natural Selection, as shown at page 11 (110/2. Harvey speaks of the perpetuation or selection of the useful, pre-supposing "a vigilant and intelligent agent," which is very much like saying that an intelligent agent is needed to see that the small stones pass through the meshes of a sieve and the big ones remain behind.) of your letter and by several of your remarks. As my book has failed to explain my meaning, it would be hopeless to attempt it in a letter. You speak in the early part of your letter, and at page 9, as if I had said that Natural Selection was the sole agency of modification, whereas I have over and over again, ad nauseam, directly said, and by order of precedence implied (what seems to me obvious) that selection can do nothing without previous variability (see pages 80, 108, 127, 468, 469, etc.), "nothing can be effected unless favourable variations occur." I consider Natural Selection as of such high importance, because it accumulates successive variations in any profitable direction, and thus adapts each new being to its complex conditions of life. The term "selection," I see, deceives many persons, though I see no more reason why it should than elective affinity, as used by the old chemists. If I had to rewrite my book, I would use "natural preservation" or "naturally preserved." I should think you would as soon take an emetic as re-read any part of my book; but if you did, and were to erase selection and selected, and insert preservation and preserved, possibly the subject would be clearer. As you are not singular in misunderstanding my book, I should long before this have concluded that my brains were in a haze had I not found by published reviews, and especially by correspondence, that Lyell, Hooker, Asa Gray, H.C. Watson, Huxley, and Carpenter, and many others, perfectly comprehend what I mean. The upshot of your remarks at page 11 is that my explanation, etc., and the whole doctrine of Natural Selection, are mere empty words, signifying the "order of nature." As the above-named clear-headed men, who do comprehend my views, all go a certain length with me, and certainly do not think it all moonshine, I should venture to suggest a little further reflection on your part. I do not mean by this to imply that the opinion of these men is worth much as showing that I am right, but merely as some evidence that I have clearer ideas than you think, otherwise these same men must be even more muddle-headed than I am; for they have no temptation to deceive themselves. In the forthcoming September (110/3. "American Journal of Science and Arts," September 1860, "Design versus Necessity," reprinted in Asa Gray's "Darwiniana," 1876, page 62.) number of the "American Journal of Science" there is an interesting and short theological article (by Asa Gray), which gives incidentally with admirable clearness the theory of Natural Selection, and therefore might be worth your reading. I think that the theological part would interest you.

You object to all my illustrations. They are all necessarily conjectural, and may be all false; but they were the best I could give. The bear case (110/4. "Origin of Species," Edition I., page 184. See Letter 120.) has been well laughed at, and disingenuously distorted by some into my saying that a bear could be converted into a whale. As it offended persons, I struck it out in the second edition; but I still maintain that there is no especial difficulty in a bear's mouth being enlarged to any degree useful to its changing habits,--no more difficulty than man has found in increasing the crop of the pigeon, by continued selection, until it is literally as big as the whole rest of the body. If this had not been known, how absurd it would have appeared to say that the crop of a bird might be increased till it became like a balloon!

With respect to the ostrich, I believe that the wings have been reduced, and are not in course of development, because the whole structure of a bird is essentially formed for flight; and the ostrich is essentially a bird. You will see at page 182 of the "Origin" a somewhat analogous discussion. At page 450 of the second edition I have pointed out the essential distinction between a nascent and rudimentary organ. If you prefer the more complex view that the progenitor of the ostrich lost its wings, and that the present ostrich is regaining them, I have nothing to say in opposition.

With respect to trees on islands, I collected some cases, but took the main facts from Alph. De Candolle, and thought they might be trusted. My explanation may be grossly wrong; but I am not convinced it is so, and I do not see the full force of your argument of certain herbaceous orders having been developed into trees in certain rare cases on continents. The case seems to me to turn altogether on the question whether generally herbaceous orders more frequently afford trees and bushes on islands than on continents, relatively to their areas. (110/5. In the "Origin," Edition I., page 392, the author points out that in the presence of competing trees an herbaceous plant would have little chance of becoming arborescent; but on an island, with only other herbaceous plants as competitors, it might gain an advantage by overtopping its fellows, and become tree-like. Harvey writes: "What you say (page 392) of insular trees belonging to orders which elsewhere include only herbaceous species seems to me to be unsupported by sufficient evidence. You cite no particular trees, and I may therefore be wrong in guessing that the orders you allude to are Scrophularineae and Compositae; and the insular trees the Antarctic Veronicas and the arborescent Compositae of St. Helena, Tasmania, etc. But in South Africa Halleria (Scrophularineae) is often as large and woody as an apple tree; and there are several South African arborescent Compositae (Senecio and Oldenburgia). Besides, in Tasmania at least, the arborescent Composites are not found competing with herbaceous plants alone, and growing taller and taller by overtopping them...; for the most arborescent of them all (Eurybia argophylla, the Musk tree) grows...in Eucalyptus forests. And so of the South African Halleria, which is a tree among trees. What the conditions of the arborescent Gerania of the Sandwich Islands may be I am unable to say...I cannot remember any other instances, nor can I accept your explanation in any other of the cases I have cited.")

In page 4 of your letter you say you give up many book-species as separate creations: I give up all, and you infer that our difference is only in degree and not in kind. I dissent from this; for I give a distinct reason how far I go in giving up species. I look at all forms, which resemble each other homologically or embryologically, as certainly descended from the same species.

You hit me hard and fairly (110/6. Harvey writes: "You ask--were all the infinitely numerous kinds of animals and plants created as eggs or seed, or as full grown? To this it is sufficient to reply, was your primordial organism, or were your four or five progenitors created as egg, seed, or full grown? Neither theory attempts to solve this riddle, nor yet the riddle of the Omphalos." The latter point, which Mr. Darwin refuses to give up, is at page 483 of the "Origin," "and, in the case of mammals, were they created bearing the false marks of nourishment from the mother's womb?" In the third edition of the "Origin," 1861, page 517, the author adds, after the last-cited passage: "Undoubtedly these same questions cannot be answered by those who, under the present state of science, believe in the creation of a few aboriginal forms, or of some one form of life. In the sixth edition, probably with a view to the umbilicus, he writes (page 423): "Undoubtedly some of these same questions," etc., etc. From notes in Mr. Darwin's copy of the second edition it is clear that the change in the third edition was chiefly due to Harvey's letter. See Letter 115.) about my question (page 483, "Origin") about creation of eggs or young, etc., (but not about mammals with the mark of the umbilical cord), yet I still have an illogical sort of feeling that there is less difficulty in imagining the creation of an asexual cell, increasing by simple division.

Page 5 of your letter: I agree to every word about the antiquity of the world, and never saw the case put by any one more strongly or more ably. It makes, however, no more impression on me as an objection than does the astronomer when he puts on a few hundred million miles to the distance of the fixed stars. To compare very small things with great, Lingula, etc., remaining nearly unaltered from the Silurian epoch to the present day, is like the dovecote pigeons still being identical with wild Rock-pigeons, whereas its "fancy" offspring have been immensely modified, and are still being modified, by means of artificial selection.

You put the difficulty of the first modification of the first protozoon admirably. I assure you that immediately after the first edition was published this occurred to me, and I thought of inserting it in the second edition. I did not, because we know not in the least what the first germ of life was, nor have we any fact at all to guide us in our speculations on the kind of change which its offspring underwent. I dissent quite from what you say of the myriads of years it would take to people the world with such imagined protozoon. In how very short a time Ehrenberg calculated that a single infusorium might make a cube of rock! A single cube on geometrical progression would make the solid globe in (I suppose) under a century. From what little I know, I cannot help thinking that you underrate the effects of the physical conditions of life on these low organisms. But I fully admit that I can give no sort of answer to your objections; yet I must add that it would be marvellous if any man ever could, assuming for the moment that my theory is true. You beg the question, I think, in saying that Protococcus would be doomed to eternal similarity. Nor can you know that the first germ resembled a Protococcus or any other now living form.

Page 12 of your letter: There is nothing in my theory necessitating in each case progression of organisation, though Natural Selection tends in this line, and has generally thus acted. An animal, if it become fitted by selection to live the life, for instance, of a parasite, will generally become degraded. I have much regretted that I did not make this part of the subject clearer. I left out this and many other subjects, which I now see ought to have been introduced. I have inserted a discussion on this subject in the foreign editions. (110/7. In the third Edition a discussion on this point is added in Chapter IV.) In no case will any organic being tend to retrograde, unless such retrogradation be an advantage to its varying offspring; and it is difficult to see how going back to the structure of the unknown supposed original protozoon could ever be an advantage.

Page 13 of your letter: I have been more glad to read your discussion on "dominant" forms than any part of your letter. (110/8. Harvey writes: "Viewing organic nature in its widest aspect, I think it is unquestionable that the truly dominant races are not those of high, but those of low organisation"; and goes on to quote the potato disease, etc. In the third edition of the "Origin," page 56, a discussion is introduced defining the author's use of the term "dominant.") I can now see that I have not been cautious enough in confining my definition and meaning. I cannot say that you have altered my views. If Botrytis [Phytophthora] had exterminated the wild potato, a low form would have conquered a high; but I cannot remember that I have ever said (I am sure I never thought) that a low form would never conquer a high. I have expressly alluded to parasites half exterminating game-animals, and to the struggle for life being sometimes between forms as different as possible: for instance, between grasshoppers and herbivorous quadrupeds. Under the many conditions of life which this world affords, any group which is numerous in individuals and species and is widely distributed, may properly be called dominant. I never dreamed of considering that any one group, under all conditions and throughout the world, would be predominant. How could vertebrata be predominant under the conditions of life in which parasitic worms live? What good would their perfected senses and their intellect serve under such conditions? When I have spoken of dominant forms, it has been in relation to the multiplication of new specific forms, and the dominance of any one species has been relative generally to other members of the same group, or at least to beings exposed to similar conditions and coming into competition. But I daresay that I have not in the "Origin" made myself clear, and space has rendered it impossible. But I thank you most sincerely for your valuable remarks, though I do not agree with them.

About sudden jumps: I have no objection to them--they would aid me in some cases. All I can say is, that I went into the subject, and found no evidence to make me believe in jumps; and a good deal pointing in the other direction. You will find it difficult (page 14 of your letter) to make a marked line of separation between fertile and infertile crosses. I do not see how the apparently sudden change (for the suddenness of change in a chrysalis is of course largely only apparent) in larvae during their development throws any light on the subject.

I wish I could have made this letter better worth sending to you. I have had it copied to save you at least the intolerable trouble of reading my bad handwriting. Again I thank you for your great liberality and kindness in sending me your criticisms, and I heartily wish we were a little nearer in accord; but we must remain content to be as wide asunder as the poles, but without, thank God, any malice or other ill-feeling.