We return home on Saturday, after three weeks of the most astounding dullness, doing nothing and thinking of nothing. I hope my Brain likes it—as for myself, it is dreadful doing nothing. (776/2. Darwin returned to Down from Sevenoaks on Saturday, October 26th, 1872, which fixes the date of the letter.)
LETTER 777. TO LADY DERBY. Down, Saturday {1874?}.
If you had called here after I had read the article you would have found a much perplexed man. (777/1. Probably Sir W. Crookes' "Researches in the Phenomena of Spiritualism" (reprinted from the "Quarterly Journal of Science"), London, 1874. Other papers by Crookes are in the "Proceedings of the Society for Psychical Research.") I cannot disbelieve Mr. Crooke's statement, nor can I believe in his result. It has removed some of my difficulty that the supposed power is not an anomaly, but is common in a lesser degree to various persons. It is also a consolation to reflect that gravity acts at any distance, in some wholly unknown manner, and so may nerve-force. Nothing is so difficult to decide as where to draw a just line between scepticism and credulity. It was a very long time before scientific men would believe in the fall of aerolites; and this was chiefly owing to so much bad evidence, as in the present case, being mixed up with the good. All sorts of objects were said to have been seen falling from the sky. I very much hope that a number of men, such as Professor Stokes, will be induced to witness Mr. Crooke's experiments.
(778/1. The two following extracts may be given in further illustration of Darwin's guiding principle in weighing evidence. He wrote to Robert Chambers, April 30th, 1861: "Thanks also for extract out of newspaper about rooks and crows; I wish I dared trust it. I see in cutting the pages {of Chambers' book, "Ice and Water"}...that you fulminate against the scepticism of scientific men. You would not fulminate quite so much if you had had so many wild-goose chases after facts stated by men not trained to scientific accuracy. I often vow to myself that I will utterly disregard every statement made by any one who has not shown the world he can observe accurately." In a letter to Dr. Dohrn, of Naples, January 4th, 1870, Darwin wrote: "Forgive me for suggesting one caution; as Demosthenes said, 'Action, action, action,' was the soul of eloquence, so is caution almost the soul of science.")
LETTER 778. TO J. BURDON SANDERSON. Down, July 16th, 1875.
Some little time ago Mr. Simon (778/1. Now Sir John Simon) sent me the last Report, and your statements about contagion deeply interested me. By the way, if you see Mr. Simon, and can remember it, will you thank him for me; I was so busy at the time that I did not write. Having been in correspondence with Paget lately on another subject, I mentioned to him an analogy which has struck me much, now that we know that sheep-pox is fungoid; and this analogy pleased him. It is that of fairy rings, which are believed to spread from a centre, and when they intersect the intersecting portion dies out, as the mycelium cannot grow where it has grown during previous years. So, again, I have never seen a ring within a ring; this seems to me a parallel case to a man commonly having the smallpox only once. I imagine that in both cases the mycelium must consume all the matter on which it can subsist.
LETTER 779. TO A. GAPITCHE.
(779/1. The following letter was written to the author (under the pseudonym of Gapitche) of a pamphlet entitled "Quelques mots sur l'Eternite du Corps Humaine" (Nice, 1880). Mr. Gapitche's idea was that man might, by perfect adaptation to his surroundings, indefinitely prolong the duration of life. We owe Mr. Darwin's letter to the kindness of Herr Vetter, editor of the well-known journal "Kosmos.")
Down, February 24th, 1880.
I suppose that no one can prove that death is inevitable, but the evidence in favour of this belief is overwhelmingly strong from the evidence of all other living creatures. I do not believe that it is by any means invariably true that the higher organisms always live longer than the lower ones. Elephants, parrots, ravens, tortoises, and some fish live longer than man. As evolution depends on a long succession of generations, which implies death, it seems to me in the highest degree improbable that man should cease to follow the general law of evolution, and this would follow if he were to be immortal.