My dear H.

Your letter has led me to think over vivisection² (I wish some new word like Anæs-section could be invented) for some hours, & I will jot down my conclusions, which will appear very unsatisfactory to you.— I have long thought physiology one of the grandest of sciences, sure sooner, or more probably later, greatly to benefit mankind; but judging from all other sciences, the benefits will accrue only indirectly in the search for abstract truth. It is certain that physiology can progress only by experiments on living animals— Therefore the proposal to limit research to points of which we can now see the bearings in regard to health &c, I look at as puerile. I thought at first it w^d be good to limit vivisection to public laboratories; but I have heard only of those in London & Cambridge & I think Oxford; but probably there may be a few others. Therefore only men living in a few great towns could carry on investigation, & this I sh^d consider a great evil. If private men, were permitted to work in their own Houses, & required a license, I do not see who is to determine whether any particular man sh^d. receive one. It is young unknown men who are the most likely to do good work.— I w^d gladly punish severely anyone who operated on an animal not rendered insensible, if the experiment made this possible; but here again I do not see that a magistrate or jury c^d. possibly determine such a point. Therefore I conclude, if (as is likely) some experiments have been tried too often, or anæsthetics have not been used, when they could been, the cure must be in the improvement of humanitarian feelings.—

Under this point of view I have rejoiced at the present agitation.³ If stringent laws are passed, & this is likely seeing how unscientific the H. of Commons is & that the gentlemen of England are humane, as long as their sports are not considered, which entail a hundred or thousand fold more suffering than the experiments of physiologists— if such laws are passed, the result will assuredly be that physiology which has been until within the last few years at a stand still in England, will languish or quite cease. It will then be carried on solely on the continent; & there will be so many the fewer workers on this grand subject, & this I sh^d. greatly regret.—

By the way F. Balfour, who has worked for 2 or 3 years in the Lab. at Cambridge, declares to George that he has never seen an experiment, except with animals rendered insensible.⁴ No doubt the names of Doctors will have great weight with the H. of Commons, but very many practioners neither know nor care anything about the progress of knowledge.

I cannot at present see my way to sign any petition, without hearing what physiologists thought w^d be its effect & then judging for myself. I certainly could not sign the paper sent me by Miss Cobbe, with its monstrous (as it seems to me) attack on Virchow for experimenting on the Trichinæ.—⁵

I am tired & so no more. | Yours affectionately | Ch Darwin

P.S. After what I have said about Balfour I must add that I have this minute heard from Frank, that Klein in the case of frogs does not always use anæsthetics, when he could do so & this is atrocious.⁶