I should like to read whole chapters on this one head, and others on the minds of the higher idiots. Nothing can be better, as it seems to me, than your several lines or sources of evidence, and the manner in which you have arranged the whole subject. Your book will assuredly be worth years of hard labour; and stick to your subject. By the way, I was pleased at your discussing the selection of varying instincts or mental tendencies; for I have often been disappointed by no one having ever noticed this notion.
I have just finished "La Psychologie, son Present et son Avenir," 1876, by Delboeuf (a mathematician and physicist of Belgium) in about a hundred pages. It has interested me a good deal, but why I hardly know; it is rather like Herbert Spencer. If you do not know it, and would care to see it, send me a postcard.
Thank Heaven, we return home on Thursday, and I shall be able to go on with my humdrum work, and that makes me forget my daily discomfort.
Have you ever thought of keeping a young monkey, so as to observe its mind? At a house where we have been staying there were Sir A. and Lady Hobhouse, not long ago returned from India, and she and he kept [a] young monkey and told me some curious particulars. One was that her monkey was very fond of looking through her eyeglass at objects, and moved the glass nearer and further so as to vary the focus. This struck me, as Frank's son, nearly two years old (and we think much of his intellect!!) is very fond of looking through my pocket lens, and I have quite in vain endeavoured to teach him not to put the glass close down on the object, but he always will do so. Therefore I conclude that a child under two years is inferior in intellect to a monkey.
Once again I heartily congratulate you on your well-earned present, and I feel assured, grand future success.
(417/2. Later in the year Mr. Darwin wrote: "I am delighted to hear that you mean to work the comparative Psychology well. I thought your letter to the "Times" very good indeed. (417/3. Romanes wrote to the "Times" August 28th, 1878, expressing his views regarding the distinction between man and the lower animals, in reply to criticisms contained in a leading article in the "Times" of August 23rd on his lecture at the Dublin meeting of the British Association.) Bartlett, at the Zoological Gardens, I feel sure, would advise you infinitely better about hardiness, intellect, price, etc., of monkey than F. Buckland; but with him it must be viva voce.
"Frank says you ought to keep a idiot, a deaf mute, a monkey, and a baby in your house.")
LETTER 418. TO G.A. GASKELL. Down, November 15th, 1878.
(418/1. This letter has been published in Clapperton's "Scientific Meliorism," 1885, page 340, together with Mr. Gaskell's letter of November 13th (page 337). Mr. Gaskell's laws are given in his letter of November 13th, 1878. They are:--
I. The Organological Law: Natural Selection, or the Survival of the Fittest.
II. The Sociological Law: Sympathetic Selection, or Indiscriminate Survival.
III. The Moral Law: Social Selection, or the Birth of the Fittest.)
Your letter seems to me very interesting and clearly expressed, and I hope that you are in the right. Your second law appears to be largely acted on in all civilised countries, and I just alluded to it in my remarks to the effect (as far as I remember) that the evil which would follow by checking benevolence and sympathy in not fostering the weak and diseased would be greater than by allowing them to survive and then to procreate.
With regard to your third law, I do not know whether you have read an article (I forget when published) by F. Galton, in which he proposes certificates of health, etc., for marriage, and that the best should be matched. I have lately been led to reflect a little, (for, now that I am growing old, my work has become [word indecipherable] special) on the artificial checks, but doubt greatly whether such would be advantageous to the world at large at present, however it may be in the distant future. Suppose that such checks had been in action during the last two or three centuries, or even for a shorter time in Britain, what a difference it would have made in the world, when we consider America, Australia, New Zealand, and S.