the fact that the wasp does not deposit the caterpillars unhurt, for thus they would disturb or perhaps destroy the young; nor does she sting them to death, for thus they would soon be in no state of proper preservation; but, as if understanding these contingencies, she inflicts a disabling wound. Yet the wasp does not feed upon caterpillars herself, nor has she ever seen a wasp provide them for her future offspring. She has never seen a worm such as will spring from her egg, nor can she know that her egg will produce a worm; and besides, she herself will be dead long before the unknown worm can be in existence. Therefore she works blindly; without knowing that her work is to subserve any useful purpose, she works to a purpose both definite and important; and her acts are uniform with those of all solitary wasps that have lived before her or that will live after her; so that we are compelled to refer these untaught actions to some constant impulse connected with the special organization of the wasp,—an innate tact, uniform throughout the species, of which we, not possessing anything of the kind, can form only a poor conception, but which we call instinct.
There have been some philosophers, however, who have exercised their ingenuity in tracing so-called instinctive actions to the operation of experience. The celebrated Doctor Erasmus Darwin gave, as an illustration of this view, his opinion that the young of animals know how to swallow from their experience of swallowing in utero. Without going into any refutation of this position, we would only remark, in passing, that the act of swallowing is not an instinctive action at all, but a purely mechanical one. Would not Doctor Darwin have rejoiced greatly, if he could have brought to the support of his theory the observation of our own great naturalist, Agassiz, who, knowing the savage snap of one of the large, full-grown Testudinata, is said to have asserted, that, under the microscope, he has seen the juvenile turtle snapping precociously in embryo?
But not only is instinct prior to all experience, it is even superior to it, and often leads animals to disregard it,—the spontaneous impulse which Nature has given them being their best guide. The carrier-pigeon or the bird of passage, taken a long distance from home by a circuitous route, trusting to this "pilot-sense," flies back in a straight course; and the hound takes the shortest way home through fields where he has never previously set foot.
The existence of instinct prior to all experience or instruction, and its perfection in the beginning, render cultivation and improvement not only unnecessary, but impossible. As it is with the individual, so it is with the race. One generation of the irrational tribes does not improve upon the preceding or educate its successor. The web which you watched the spider weaving in your open window last summer, carefully measuring off each radius of her wheel and each circular mesh by one of her legs, was just such a web as the spider wove of old when she was pronounced to be "little upon the earth, yet exceeding wise."
This incapacity for education is what so widely separates instinct from the rational powers of man. Man gathers knowledge and transmits it from generation to generation. He is not born with a ready skill, but with a capacity for it. His mind is formed destitute of all connate knowledge, that it may acquire the knowledge of all things. "Man's imperfection at his nativity is his perfection; while the perfection of brutes at their nativity is their imperfection." No rational being has ever arrived at such perfection that he cannot still improve; he can travel on from one attainment to another in a perpetual progress of improvement. He is, moreover, free to choose his own path of action; while the being of instinct is governed by a power which is not subject to his will, and which confines him to a narrow path which he cannot leave. But instinct, within its narrow limits, in many cases quite transcends reason in its achievements.
