Among animals the necessity of finding food is the great and unfailing stimulus towards the exercise of their vital functions; food which may, as we all know, be vegetable, animal, or a combination of both kinds. It is evident that in the case of carnivorous animals the object which satisfies this desire is a living subject, of which it is necessary to become possessed by arts, wiles, sometimes by a fierce and cruel conflict. In these cases, animals are in constant communication with an animal world resembling their own, and the objective reality is for the most part resolved into living subjects, endowed with consciousness and will. But neither is the vegetable food of herbivorous, frugivorous, and graminivorous animals regarded by them, as it is by us, as a material and unconscious satisfaction of their wants; these grasses, grains, and leaves appear to animals to be living powers which it is necessary to conquer, animated subjects endowed with life, but for the most part inoffensive, and which, unlike the living prey of carnivora, offer no resistance. Observe the way in which an herbivorous or graminivorous animal becomes excited and angry when the branch or the ear of corn obstinately adheres to the ground, or offers any other difficulty to his immediate desire of obtaining food; he acts like one who has to do with a resisting power. Observe how, when they are quietly stripping the bough, picking out the grains, or eating the grass, they become suspicious, or fly away if there should be any unusual movement in the bough, the ears of corn, or the grass. In one way or another their food is regarded as a subject endowed with sympathetic and deliberate consciousness. And every one must have observed that animals at play act towards inanimate objects as if they were conscious and endowed with will. Every object of animal perception is therefore felt, or implicitly assumed, to be a living, conscious, acting subject. This is due to the external reflection and projection of the intrinsic and sentient faculty, and therefore--since an animal has not the duplex faculty of deliberate and reflex attention--he cannot attain to the conception of simple external reality, of cosmic things and phenomena. Every object, every phenomenon is for him a deliberating power, a living subject, in which consciousness and will act as they do in himself. There are undoubtedly in the vast series of beings which compose the order of nature, and which he is able to perceive, degrees, differences, and varieties of energy, power, and efficacy with respect to himself and to the normal exercise of his life. But he transfuses into all, in proportion to the effects which result from them, his own nature, and modifies them in accordance with the intrinsic form of his consciousness, his emotions, and his instincts.