The subject is again dealt with in “The Progress of Science,” 1887 ("Collected Essays” 1 122 seq.) from which I may quote two sentences:—­]

The history of all branches of science proves that they must attain a considerable stage of development before they yield practical “fruits”; and this is eminently true of physiology.

Unless the fanaticism of philozoic sentiment overpowers the voice of humanity, and the love of dogs and cats supersedes that of one’s neighbour, the progress of experimental physiology and pathology will, indubitably, in course of time, place medicine and hygiene upon a rational basis.

[The dangers of prohibition by law are discussed in a letter to Sir W. Harcourt:—­]

You wish me to say what, in my opinion, would be the effect of the total suppression of experiments on living animals on the progress of physiological science in this country.

I have no hesitation in replying that it would almost entirely arrest that progress.  Indeed, it is obvious that such an effect must follow the measure, for a man can no more develop a true conception of living action out of his inner consciousness than he can that of a camel.  Observation and experiment alone can give us a real foundation for any kind of Natural Knowledge, and any one who is acquainted with the history of science is aware that not a single one of all the great truths of modern physiology has been established otherwise than by experiment on living things.

Happily the abolition of physiological experiment in this country, should such a fatal legislative mistake ever be made, will be powerless to arrest the progress of science elsewhere.  But we shall import our physiology as we do our hock and our claret from Germany and France; those of our young physiologists and pathologists who can afford to travel will carry on their researches in Paris and in Berlin, where they will be under no restraint whatever, or it may be that the foreign laboratories will carry out the investigations devised here by the few persons who have the courage, in spite of all obstacles, to attempt to save British science from extinction.

I doubt if such a result will contribute to the diminution of animal suffering.  I am sure that it will do as much harm as anything can do to the English school of Physiology, Pathology, and Pharmacology, and therefore to the progress of rational medicine.

[Another letter on the subject may be given, which was written to a student at a theological college, in reply to a request for his opinion on vivisection, which was to be discussed at the college debating society.]

Grand Hotel, Eastbourne, September 29, 1890.

Dear Sir,

I am of the opinion that the practice of performing experiments on living animals is not only reconcilable with true humanity, but under certain circumstances is imperatively demanded by it.

Experiments on living animals are of two kinds.  First, those which are made upon animals which, although living, are incapable of sensation, in consequence of the destruction or the paralysis of the sentient machinery.