Vegetarianism is the neglect by one being to suppress another for nutritive purposes. I believe in it. I believe I should neglect to suppress the interests and lives of _non_-human beings for identically the same reason I should neglect to suppress the interests and lives of _human_ beings. The exploitation of birds and quadrupeds for human whim or convenience is an offense not different in kind from the offenses denounced in human statutes as robbery and murder. And the same logic which impels abstinence from one of these offenses impels everyone who has the power to be consistent to refrain from all of them.
There is, in fact, but one crime in the universe and all varieties of impropriety whatsoever are aspects or phases of this crime. It is the crime of _exploitation_—the suppression of the interests, lives, or welfares of some beings for the whim or convenience of others—the neglect to recognize the equal or the approximately equal rights of all to life, consideration and happiness—the crime of doing to others as you would that others would _not_ do to you.
I look back over the ages of this world—not the ages of human history simply, for the history of the human species is but a little section, the remembered chapter, in the history of the evolutions which have been performed by mundane life. I look back to the beginning of life on this planet—back 50,000,000 of years ago, when the first protoplasmic specks sprawled in primeval seas. Life originated in the sea fifteen hundred thousand human generations ago. After ages of evolution it crept out upon the continents, subsequently entered the forests, climbed and clambered among the trees, became endowed with perpendicularity and hands, descended and walked upon the soil, invented agriculture, built cities and states—and here we are. Human civilization is but the van, the hither terminus, of an evolutional process which had its beginning away back in the protoplasm of primeval slime. The philosopher is the remote posterity of the meek and lowly monad.
Now, this whole enterprise, this entire process of biological evolution, has been accomplished by the survival from age to age of the fittest to survive; that is, by the subjection and elimination of the weak and the simple by the more powerful and sophisticated, And the disposition to exploit manifested by every animal that breathes, from philosopher to fish, is a disposition which has been implanted in the natures of living beings by the necessities of evolution. The great task of reforming the universe, therefore, is the task of eliminating from the natures of its inhabitants the disposition to be inhospitable, egoistic and merciless, which has been everywhere developed by evolution.