He also says the method of investigation you have followed is the only one proper to such a subject.
It is easy for an antagonistic reviewer, when he finds it difficult to answer your arguments, to attempt to dispose of the whole matter by uttering some such commonplace as "This is not a Baconian induction."
I expect shortly to be spending a few days in your neighbourhood, and if I should not be intruding upon you, I should esteem it a great favour if you will allow me to call on you, and have half an hour's conversation with you.
As far as I am personally concerned, I am sure I ought to be grateful to you, for since my accident nothing has given me so much pleasure as the perusal of your book. Such studies are now a great resource to me.
LETTER 130. TO C. LYELL. 2, Hesketh Terrace, Torquay [August 2nd, 1861].
I declare that you read the reviews on the "Origin" more carefully than I do. I agree with all your remarks. The point of correlation struck me as well put, and on varieties growing together; but I have already begun to put things in train for information on this latter head, on which Bronn also enlarges. With respect to sexuality, I have often speculated on it, and have always concluded that we are too ignorant to speculate: no physiologist can conjecture why the two elements go to form a new being, and, more than that, why nature strives at uniting the two elements from two individuals. What I am now working at in my orchids is an admirable illustration of the law. I should certainly conclude that all sexuality had descended from one prototype. Do you not underrate the degree of lowness of organisation in which sexuality occurs--viz., in Hydra, and still lower in some of the one-celled free confervae which "conjugate," which good judges (Thwaites) believe is the simplest form of true sexual generation? (130/1. See Letter 97.) But the whole case is a mystery.
There is another point on which I have occasionally wished to say a few words. I believe you think with Asa Gray that I have not allowed enough for the stream of variation having been guided by a higher power. I have had lately a good deal of correspondence on this head. Herschel, in his "Physical Geography" (130/2. "Physical Geography of the Globe," by Sir John F.W. Herschel, Edinburgh, 1861. On page 12 Herschel writes of the revelations of Geology pointing to successive submersions and reconstructions of the continents and fresh races of animals and plants. He refers to a "great law of change" which has not operated either by a gradually progressing variation of species, nor by a sudden and total abolition of one race...The following footnote on page 12 of the "Physical Geography" was added in January, 1861: "This was written previous to the publication of Mr. Darwin's work on the "Origin of Species," a work which, whatever its merit or ingenuity, we cannot, however, consider as having disproved the view taken in the text. We can no more accept the principle of arbitrary and casual variation and natural selection as a sufficient account, per se, of the past and present organic world, than we can receive the Laputan method of composing books (pushed a outrance) as a sufficient one of Shakespeare and the "Principia." Equally in either case an intelligence, guided by a purpose, must be continually in action to bias the directions of the steps of change--to regulate their amount, to limit their divergence, and to continue them in a definite course. We do not believe that Mr. Darwin means to deny the necessity of such intelligent direction. But it does not, so far as we can see, enter into the formula of this law, and without it we are unable to conceive how far the law can have led to the results. On the other hand, we do not mean to deny that such intelligence may act according to a law (that is to say, on a preconceived and definite plan). Such law, stated in words, would be no other than the actual observed law of organic succession; a one more general, taking that form when applied to our own planet, and including all the links of the chain which have disappeared.