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Darwin Correspondence Project

From Asa Gray   22–30 March 1863

Cambridge [Massachusetts]

22. March ’63

My Dear Darwin

Argyle’s article on the Supernatural—to which you called my attention a long while ago,1 I never happened to see till to-day—when I have read it through. It is quite clever—not deep, but clear, and I think useful   I see no occasion for finding fault with him—except in his attempts now and then to direct a little odium against you—which is unhandsome—for his main points are those I hammered out in Atlantic. &c—indeed I see signs of his having read the same.2 But it is hardly fair of him, after expressing his complete conviction that where the operation of natural causes can be clearly traced, the implication of design—upon its appropriate evidence—is not thereby rendered less certain or less convincing.—to go on to speak of derivation-doctrines in a way that implies the contrary.3

Of course we believers in real design, make the most of your frank and natural terms, ‘contrivance, purpose”, &c”—and pooh-pooh your endeavors to resolve such contrivances into necessary results of certain physical processes, and make fun of the race between long noses and long nectaries!4

23d March.

Dr. Wyman5—who is a sharp fellow tells me that—on the authority of the historian Prescott,—the Incas of Peru for—no one knows how long—married their sisters—to keep the perfect purity of the blood.6 Quere. How did this strong case of close-breeding operate? Did they run out thereby? Wyman thinks there is no evidence of it.

If it is true—and the Incas stood it for a long course of generations, you must look to it—for it will bear hard against your theory of the necessity of crossing.7

If they run out, you will have a good case.

P.S. 30 March.

I hear from Hooker that you are poorly,—am very sorry to hear it.—8 hope it is something very temporary. I have been laid up two or three days with a sort of influenza and a bad throat,—now much better.

I have sent to Silliman extracts from Bates’ paper, embracing almost all about mimetic analogy,—8 or 10 pages. My only fear is Silliman will demur to printing it.9

You think Lyell too non-comittal and timid. Well Huxley makes up for it, I should think!10

Ever dear Darwin | Yours cordially | Asa Gray

CD annotations

End of letter: ‘Ohio—cousins’11 ink


In October 1862, George Douglas Campbell, eighth duke of Argyll, published an anonymous review entitled ‘The supernatural’ in the Edinburgh Review, in which he discussed Orchids together with five books on miracles and the supernatural ([Campbell] 1862). CD told Gray of the review in his letter of 23 November [1862] (Correspondence vol. 10), saying that while it was ‘clever’, it did not remove any of the ‘difficulties of Theology’.
The reference is to three articles on Origin published by Gray in 1860 (A. Gray 1860b), and reprinted as a pamphlet on CD’s initiative (A. Gray 1861a); Campbell’s name appears on the list of people to whom CD planned to send a copy of A. Gray 1861a (see Correspondence vol. 9, Appendix III). Like Gray, Campbell argued that the explanation of natural phenomena, including the origination of new species, in terms of material causes did not negate the widely held view that the design apparent in nature resulted from the intentions of a divine designer.
In [Campbell] 1862, p. 388, Campbell stated that the ‘various hypotheses of development’, of which he considered CD’s to be ‘only a new and special version’, were ‘utterly destitute of proof’ and involved ‘such violations of, or departures from, all that we know of the existing order of things, as to deprive them absolutely of all scientific basis’. Moreover, while Campbell praised CD’s teleological analysis of the floral structure of orchids, he ridiculed his attempt to explain how the structures had arisen by successive modifications (ibid., pp. 391–5).
Referring to CD’s frequent use of words such as ‘contrivance’ and ‘purpose’ ([Campbell] 1862, pp. 292–3), Campbell commented: ‘It is curious to observe the language which this most advanced disciple of pure naturalism instinctively uses when he has to describe the complicated structure of this curious order of plants.’ Gray also refers to the fact that Campbell ridiculed CD’s attempt to account for the great length of the nectary of the Madagascan orchid, Angraecum sesquipedale, by reference to a ‘race in gaining length between the nectary of the Angræcum and the proboscis of certain moths’; in his account, Campbell had substituted the word ‘nose’ for ‘proboscis’ (see [Campbell] 1862, pp. 394–5, and Orchids, pp. 179–203).
The anatomist and ethnologist Jeffries Wyman was one of Gray’s colleagues at Harvard University (DSB).
William Hickling Prescott. CD read Prescott’s History of the conquest of Peru (Prescott 1847) in May 1850, describing it as ‘goodish’ (see Correspondence vol. 4, Appendix IV, 119: 22b).
Gray refers to CD’s belief that it was a ‘general law of nature . . . that no organic being self-fertilises itself for an eternity of generations; but that a cross with another individual is occasionally—perhaps at very long intervals—indispensable’ (Origin, p. 97). See also Correspondence vol. 10, letter to Asa Gray, 26[–7] November [1862]. CD did not refer to Prescott’s observation in print, but see the letter to Asa Gray, 20 April [1863].
In his letter to Joseph Dalton Hooker of 5 March [1863], CD reported that he had been particularly ill for ten days, with ‘much sickness & weakness’.
Henry Walter Bates had sent Gray a copy of Bates 1861, in which he explained mimetic resemblances in South American butterflies in terms of natural selection, after CD had persuaded Gray to attempt to have it reviewed in the American Journal of Science and Arts, of which Gray was one of the contributing editors (see letter to H. W. Bates, 12 January [1863], and letter from H. W. Bates, 17 January [1863]). See also letter to H. W. Bates, 4 March [1863] and n. 4. The abstracts sent by Gray were so extensive that the journal’s general editors, who included Benjamin Silliman and his son Benjamin Silliman Jr, insisted that they be held over for the July number of the journal; ultimately, Gray decided to write a review abstract of the paper instead (A. Gray 1863a), although this was not published until the September 1863 issue of the journal (see letters from Asa Gray, 13 April 1863, 7 July 1863, and 21 July 1863).
See letter to Asa Gray, 23 February [1863] and n. 16. The references are to Charles Lyell’s Antiquity of man (C. Lyell 1863a), and Thomas Henry Huxley’s Evidence as to man’s place in nature (T. H. Huxley 1863b).


Bates, Henry Walter. 1861. Contributions to an insect fauna of the Amazon valley. Lepidoptera: Heliconidæ. [Read 21 November 1861.] Transactions of the Linnean Society of London 23 (1860–2): 495–566.

[Campbell, George Douglas.] 1862. [Review of Orchids and other works.] Edinburgh Review 116: 378–97.

Correspondence: The correspondence of Charles Darwin. Edited by Frederick Burkhardt et al. 29 vols to date. Cambridge: Cambridge University Press. 1985–.

DSB: Dictionary of scientific biography. Edited by Charles Coulston Gillispie and Frederic L. Holmes. 18 vols. including index and supplements. New York: Charles Scribner’s Sons. 1970–90.

Orchids: On the various contrivances by which British and foreign orchids are fertilised by insects, and on the good effects of intercrossing. By Charles Darwin. London: John Murray. 1862.

Origin: On the origin of species by means of natural selection, or the preservation of favoured races in the struggle for life. By Charles Darwin. London: John Murray. 1859.

Prescott, William Hickling. 1847. History of the conquest of Peru, with a preliminary view of the civilization of the Incas. 2 vols. London: Richard Bently.


Discusses the Duke of Argyll’s article on the supernatural [Edinburgh Rev. 116 (1862): 378–97].

Has heard that the Incas married their sisters; this may be worth investigating as a case of inbreeding.

Letter details

Letter no.
Asa Gray
Charles Robert Darwin
Sent from
Cambridge Mass.
Source of text
DAR 165: 131
Physical description
ALS 4pp †

Please cite as

Darwin Correspondence Project, “Letter no. 4056,” accessed on 21 May 2024,

Also published in The Correspondence of Charles Darwin, vol. 11