Henry S. Salt (1851-1939) on Animal Rights

Nor is it true that the worth of an animal's life, any more than of a man's, can be measured simply by the amount of "agreeable sensation," a fallacy often put forward by those who cage animals in menageries, on the plea that they are there well tended and saved from the struggle for existence. To live one's own natural life, to realize one's self, is the true moral purpose of man and animal equally, and the wrong done by the unnecessary cramping and thwarting of animal individuality, as in the turning of an active intelligent being into a prisoner or pet, cannot really be compensated by the gift of any material "comforts." Compare the life of the wild bison with that of the stall-fed ox, or that of the sheepdog with the pampered pug, and the moral can hardly be overlooked. An animal has his proper work to do in the world, his own life to live, as surely as a man; and those who scoff at this idea, and deny individuality to animals, should remember that there was a time, under the Greek and Roman civilization, when it was held to be doubtful whether a slave, in like manner, had any claim to be regarded as a person.

(Henry S. Salt, "The Rights of Animals," International Journal of Ethics 10 [January 1900]: 206-22, at 209 [italics in original])