There is hardly any human action, feeling, or belief, which has not been ranged under the term instinct. Hunger and thirst have been called instincts; so have the faculty of speech, the use of the right hand in preference to the left, the love of society, the desire to possess property, the desire to avoid danger and prolong life, and the belief in supernatural agencies, upon which is engrafted the religious sentiment. We cannot, in this paper, attempt to analyze these and many other similar examples which have been given as illustrations of instinct in treatises of high repute, and show that they do not at all come within that class of actions which we contrast with reason. In regard to those actions of early infancy which have often been adduced as illustrations of instinct, the physiologists of the present day are agreed that they are as mechanical as the act of breathing. To place these upon the same level with the complex and wonderful operations of the bee, the ant, and the beaver, is to admit that the instincts of the latter are merely reflex actions following impressions on the nerves of sense. On the other hand, whether the animals inferior to man ever exercise any conscious process of reasoning is a question which has often been discussed, and upon which there is no general agreement. Instances of the remarkable sagacity of some domesticated animals are often adduced as proofs of reasoning on their part. Some of these wonderful feats may be traced to the unconscious faculty of imitation, which even in man often appears as a blind propensity, although he exercises an active and rational imitation as well. Sometimes the mere association of ideas, or the perception by animals that one thing is accompanied by another or that one event follows another, is mistaken for that higher principle which in man judges, reflects, and understands causes and effects. When the dog sees his master take down his gun, his blandishments show that he anticipates a renewal of the pleasures of the chase. He does not reflect upon past pleasures; but, seeing the gun in his master's hand, a confused idea of the feelings that were associated with the gun in times past is called up. So the ox and the horse learn to associate certain movements with the voice and gesture of man. And so a fish, about the most stupid of all animals, comes to a certain spot at a certain signal to be fed. These combinations are quite elementary. This is quite another thing from that reciprocal action of ideas on each other by which man perceives the relations of things, understands the laws of cause and effect, and not only forms judgments of the past, but draws conclusions which are laws for the future. We find in the brute no power of attending to and arranging its thoughts,--no power of calling up the past at will and reflecting upon it. The animal has the faculty of memory, and, when this is awakened, the object remembered may be accompanied by a train or attendance of