LETTER 88. J.D. HOOKER TO CHARLES DARWIN. [1859 or 1860.]
I have had another talk with Bentham, who is greatly agitated by your book: evidently the stern, keen intellect is aroused, and he finds that it is too late to halt between two opinions. How it will go we shall see. I am intensely interested in what we shall come to, and never broach the subject to him. I finished the geological evidence chapters yesterday; they are very fine and very striking, but I cannot see they are such forcible objections as you still hold them to be. I would say that you still in your secret soul underrate the imperfection of the Geological Record, though no language can be stronger or arguments fairer and sounder against it. Of course I am influenced by Botany, and the conviction that we have not in a fossilised condition a fraction of the plants that have existed, and that not a fraction of those we have are recognisable specifically. I never saw so clearly put the fact that it is not intermediates between existing species we want, but between these and the unknown tertium quid.
You certainly make a hobby of Natural Selection, and probably ride it too hard; that is a necessity of your case. If the improvement of the creation-by-variation doctrine is conceivable, it will be by unburthening your theory of Natural Selection, which at first sight seems overstrained--i.e., to account for too much. I think, too, that some of your difficulties which you override by Natural Selection may give way before other explanations. But, oh Lord! how little we do know and have known to be so advanced in knowledge by one theory. If we thought ourselves knowing dogs before you revealed Natural Selection, what d--d ignorant ones we must surely be now we do know that law.
I hear you may be at the Club on Thursday. I hope so. Huxley will not be there, so do not come on that ground.
LETTER 89. TO T.H. HUXLEY. January 1st [1860].
I write one line merely to thank you for your pleasant note, and to say that I will keep your secret. I will shake my head as mysteriously as Lord Burleigh. Several persons have asked me who wrote that "most remarkable article" in the "Times." (89/1. The "Times," December 26th, 1859, page 8. The opening paragraphs were by one of the staff of the "Times." See "Life and Letters," II., page 255, for Mr. Huxley's interesting account of his share in the matter.) As a cat may look at a king, so I have said that I strongly suspected you. X was so sharp that the first sentence revealed the authorship. The Z's (God save the mark) thought it was Owen's! You may rely on it that it has made a deep impression, and I am heartily glad that the subject and I owe you this further obligation. But for God's sake, take care of your health; remember that the brain takes years to rest, whilst the muscles take only hours. There is poor Dana, to whom I used to preach by letter, writes to me that my prophecies are come true: he is in Florence quite done up, can read nothing and write nothing, and cannot talk for half an hour. I noticed the "naughty sentence" (89/2. Mr. Huxley, after speaking of the rudimental teeth of the whale, of rudimental jaws in insects which never bite, and rudimental eyes in blind animals, goes on: "And we would remind those who, ignorant of the facts, must be moved by authority, that no one has asserted the incompetence of the doctrine of final causes, in its application to physiology and anatomy, more strongly than our own eminent anatomist, Professor Owen, who, speaking of such cases, says ("On the Nature of Limbs," pages 39, 40), 'I think it will be obvious that the principle of final adaptations fails to satisfy all the conditions of the problem.'"--"The Times," December 26th, 1859.) about Owen, though my wife saw its bearing first. Farewell you best and worst of men!
That sentence about the bird and the fish dinners charmed us. Lyell wrote to me--style like yours.
Have you seen the slashing article of December 26th in the "Daily News," against my stealing from my "master," the author of the "Vestiges?"
LETTER 90. TO J.L.A. DE QUATREFAGES. [Undated]
How I should like to know whether Milne Edwards has read the copy which I sent him, and whether he thinks I have made a pretty good case on our side of the question. There is no naturalist in the world for whose opinion I have so profound a respect. Of course I am not so silly as to expect to change his opinion.
LETTER 91. TO C. LYELL.
(91/1. The date of this letter is doubtful; but as it evidently refers to the 2nd edition of the "Origin," which appeared on January 7th, 1860, we believe that December 9th, 1859, is right. The letter of Sedgwick's is doubtless that given in the "Life and Letters," II., page 247; it is there dated December 24th, 1859, but from other evidence it was probably written on November 24th)
[December?] 9th [1859].
I send Sedgwick's letter; it is terribly muddled, and really the first page seems almost childish.
I am sadly over-worked, so will not write to you. I have worked in a number of your invaluable corrections--indeed, all as far as time permits. I infer from a letter from Huxley that Ramsay (91/2. See a letter to Huxley, November 27th, 1859, "Life and Letters," II., page 282.) is a convert, and I am extremely glad to get pure geologists, as they will be very few. Many thanks for your very pleasant note. What pleasure you have given me. I believe I should have been miserable had it not been for you and a few others, for I hear threatening of attacks which I daresay will be severe enough. But I am sure that I can now bear them.
LETTER 92. TO T.H. HUXLEY.
(92/1. The point here discussed is one to which Mr. Huxley attached great, in our opinion too great, importance.)
Down, January 11th [1860?].
I fully agree that the difficulty is great, and might be made much of by a mere advocate. Will you oblige me by reading again slowly from pages 267 to 272. (92/2. The reference is to the "Origin," Edition I.: the section on "The Fertility of Varieties when crossed, and of their Mongrel Offspring" occupies pages 267-72.) I may add to what is there said, that it seems to me quite hopeless to attempt to explain why varieties are not sterile, until we know the precise cause of sterility in species.
Reflect for a moment on how small and on what very peculiar causes the unequal reciprocity of fertility in the same two species must depend. Reflect on the curious case of species more fertile with foreign pollen than their own. Reflect on many cases which could be given, and shall be given in my larger book (independently of hybridity) of very slight changes of conditions causing one species to be quite sterile and not affecting a closely allied species. How profoundly ignorant we are on the intimate relation between conditions of life and impaired fertility in pure species!
The only point which I might add to my short discussion on this subject, is that I think it probable that the want of adaptation to uniform conditions of life in our domestic varieties has played an important part in preventing their acquiring sterility when crossed. For the want of uniformity, and changes in the conditions of life, seem the only cause of the elimination of sterility (when crossed) under domestication. (92/3. The meaning which we attach to this obscure sentence is as follows: Species in a state of nature are closely adapted to definite conditions of life, so that the sexual constitution of species A is attuned, as it were, to a condition different from that to which B is attuned, and this leads to sterility. But domestic varieties are not strictly adapted by Natural Selection to definite conditions, and thus have less specialised sexual constitutions.) This elimination, though admitted by many authors, rests on very slight evidence, yet I think is very probably true, as may be inferred from the case of dogs. Under nature it seems improbable that the differences in the reproductive constitution, on which the sterility of any two species when crossed depends, can be acquired directly by Natural Selection; for it is of no advantage to the species. Such differences in reproductive constitution must stand in correlation with some other differences; but how impossible to conjecture what these are! Reflect on the case of the variations of Verbascum, which differ in no other respect whatever besides the fluctuating element of the colour of the flower, and yet it is impossible to resist Gartner's evidence, that this difference in the colour does affect the mutual fertility of the varieties.
The whole case seems to me far too mysterious to rest (92/4. The word "rest" seems to be used in place of "to serve as a foundation for.") a valid attack on the theory of modification of species, though, as you say, it offers excellent ground for a mere advocate.
I am surprised, considering how ignorant we are on very many points, [that] more weak parts in my book have not as yet been pointed out to me. No doubt many will be. H.C. Watson founds his objection in MS. on there being no limit to infinite diversification of species: I have answered this, I think, satisfactorily, and have sent attack and answer to Lyell and Hooker. If this seems to you a good objection, I would send papers to you. Andrew Murray "disposes of" the whole theory by an ingenious difficulty from the distribution of blind cave insects (92/5. See "Life and Letters, Volume II., page 265. The reference here is to Murray's address before the Botanical Society, Edinburgh. Mr. Darwin seems to have read Murray's views only in a separate copy reprinted from the "Proc. R. Soc. Edin." There is some confusion about the date of the paper; the separate copy is dated January 16th, while in the volume of the "Proc. R. Soc." it is February 20th. In the "Life and Letters," II., page 261 it is erroneously stated that these are two different papers.); but it can, I think, be fairly answered.