"Those who experiment with operations or the use of drugs upon animals, or inoculate them with diseases, so as to be able to bring help to mankind with the results gained, must never quiet any misgivings they feel with the general reflection that their cruel proceedings aim at a valuable result. They must first have considered in each individual case whether there is a real necessity to force upon any animal this sacrifice for the sake of mankind. And they must take the most anxious care to mitigate as much as possible the pain inflicted. How much wrong is committed in scientific institutions through neglect of anaesthetics, which to save time or trouble are not administered! How much, too, through animals being subjected to torture merely to demonstrate to students generally known phenomena! By the very fact that animals have been subjected to experiments, and have by their pain won such valuable results for suffering humanity, a new and special relation of solidarity has been established between them and us. From that springs for each one of us a compulsion to do to every animal all the good we possibly can. By helping an insect when it is in difficulties, I am only attempting to cancel part of man's ever new debt to the animal world."