There are only about twenty laboratories in France where experiments on animals are made. Let us allow that there are twenty in England, twenty in Italy, forty in Germany, and fifty in other countries, making a total of 150 laboratories. If we suppose that a dog, a cat, and a rabbit are sacrificed every day in each of these laboratories, we should certainly exaggerate.
Let us suppose, nevertheless, that it is so; and let us even admit five victims a day, with 300 working days in the year, which is also an evident exaggeration: this will make about 200,000 victims a year. This number, which seems very considerable, is in reality very small, if we put it against the enormous number of living beings. Probably about two thousand millions of mammals die every year, so that the proportion of animals that suffer a little (and very little) through the act of man in his search for knowledge is one in 10,000, in other words, a negligible quantity.
In the immense earthly universe are thousands and thousands of pains, of fierce, incessant struggles between living animals. Every rock in the ocean, every tree in the forest, shelters ferocious combats, and is the constant scene of painful death-agonies. Darwin has admirably shown that life is a struggle for life, that the weak are crushed by the strong, and that the voice of living nature is a cry of distress rather than a hymn of joy. Therefore, in this universal concert of animal pain and of human pain, the slight pain of animals experimented upon is a little thing, and from an absolute point of view we have the right to disregard it.
Think well over it all for a moment. By giving an experimental disease to a rabbit, for example, I scarcely change its lot. If I had left it to itself, in one, two, or perhaps three years it would have been attacked by another disease, probably more cruel than the tuberculosis with which I infected it. The lot of dogs which die of old age is scarcely enviable. How many poor old dogs have I seen, impotent from rheumatism, completely blind, no longer able to crawl about, covered with disgusting ulcers, seeming to beg for the finishing stroke which would put an end to their misery! And old, worn-out horses! What a spectacle! This residuum of existence of old animals is truly pitiable, and, taking everything into consideration, it is not an enormous dose of happiness we have left them in not sacrificing them when they were young.