My dear M^rs. D.

The answer to your two letters to my wife I have pleasure in giving you my opinion, which you can communicate to anyone, as you may think fit; but I must beg you to observe that I am not a physiologist & that my opinion can have no special value.—²

I should regret that any girl who wished to learn physiology sh^d. be checked, because it seems to me that this science is the best or sole one for giving to any person an intelligent view of living beings, & thus to check that credulity on various points which is so common with ordinary men & women. I sh^d look at it as a Sin to discourage any boy from studying physiology who had the wish to do so; & I make the distinction between a boy & a girl, because as yet no woman has advanced the science. I believe much physiology c^d. be learned without seeing any experiments performed or any organ in action; but I do not believe that a person could learn several parts of the subject with ⁠⟨⁠the⁠⟩⁠ vividness & clearness, which is necessary for well instructing others, unless he saw some of our organs in action.— All that I have said here with respect to ordinary students applies with greatly increased force to medical students; though no doubt very many perhaps most medical men practice their profession by the mere rule of thumb. With respect to you not liking a girl to see an animal operated on, though quite insensible, I can quite understand it & sh^d. sympathise fully with you, if it were out of mere idle curiosity; but if a person with a wish ⁠⟨⁠to⁠⟩⁠ learn physiology was thus prevented, I sh^d. consider it a weakness.— I may add that I have bitterly repented this very weakness in my own case, as I c^d. not get over my horror at seeing men dissected when I was young.—³ Even to take the extreme case of an animal becoming sensible before the operation was over, it w^d take only a few seconds either to kill it or render it again insensible. Nor can I see the least reason to suppose it w^d suffer more during such few seconds than it w^d do for hours during any severe illness to which men & animals are liable. By dwelling too much on humanity, though Heaven knows this until lately has been a rare error, do you not think that there is danger of compassion becoming morbid?⁴

Pray believe me, dear M^rs D | Yours very sincerely | Ch Darwin