"The chief activities of beings, both human and non-human, are put forth, directly or indirectly, for the purpose of procuring food. The suppression, entire or partial, of one being by another for nutritive purposes is, therefore, the form of the most frequent and excessive egoism. The lowly forms of life—the worms, echinoderms, mollusks, and the like—are, for the most part, vegetarians. So, also, are prevalently the insects, birds, rodents, and ungulates. These creatures are not, as a rule, aggressively harmful to each other, chiefly indifferent. But upon these inoffensive races feed with remorseless maw the reptilia, the insectivora, and the carnivora. These being-eaters cause to the earth-world its bloodiest experiences. It is their nature (established organically by long selection, or, as in the case of man, acquired tentatively) to subsist, not on the kingdom of the plant, the natural and primal storehouse of animal energy, but on the skeletons and sensibilities of their neighbors and friends. The serpent dines on the sparrow and the sparrow ingulfs the gnat; the tiger slays the jungle-fowl and the coyote plunders the lamb; the seal subsists on fish and the ursus maritimus subsists on seal; the ant enslaves the aphidae and man eats and enslaves what can not get away from him. Life riots on life—tooth and talon, beak and paw. It is a sickening contemplation, but life everywhere, in its aspect of activity, is largely made up of the struggle by one being against another for existence—of the effort by one being to circumvent, subjugate, or destroy another, and of the counter effort to reciprocate or escape."