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among which they class the beating of the heart, the peristaltic motion of the bowels, the secretions in the animal economy, and the like. But as these motions are regular and involuntary, they are more properly considered as automatic or mechanical, and are classed with the phenomena of life rather than with those of instinct. Operations corresponding to them, or exactly similar, are carried on in vegetables ; and some of them, even in animals after death, may be renewed through the application of a galvanic battery. At any rate, as they are wholly independent of the action of mind, they may be put aside in the present investigation.
As the appetites and passions seek their own gratification without the aid of reason, and frequently in spite of it, they also are often called instinctive in their operation. But these are common to man and the brute, and they differ, at least in one important respect, from those instincts of the lower animals which are usually contrasted with human reason. The objects towards which they are directed are prized for their own sake ; they are sought as ends, while instinct teaches brutes to do many things which are needed only as means for the attainment of some ulterior purpose. Thus, instinct enables a spider to entrap his prey, while appetite only leads him to devour it when in his possession. Nay, the two impulses often act in opposition to each other, as when the bird restrains its own hunger for the sake of feeding its young. Appetite is blind, and affords a motive, but no guidance, for effort ; instinct, on the other hand, both supplies an object for action, and points out a course for its attainment. It is true that appetite sometimes appears to direct the choice, yet so far only as the want of it leads the animal to reject unsuitable food, and to devour that which is adapted for its physical organization. That a dog will not eat hay, nor a horse swallow raw meat, is no more a proof of instinct, than the corresponding fact in man, that sweet things are pleasant to the taste, while bitters are disagreeable, is an indication of
Yet the two are often confounded both by physiologists and metaphysicians. Thus, the celebrated experiment of Galen is quoted by Dugald Stewart, as it was devised by its author, in order to show that instinct is antecedent to experience, when it only proves that the appetites of animals distinguish between different classes of food, or that they mani
fest preference and aversion. “On dissecting,” says Galen, “a goat great with young, I found a brisk embryon, and having detached it from the matrix, and snatched it away before it saw its dam, I brought it into a room where there were many vessels, some filled with wine, others with oil, some with honey, others with milk, or some other liquor, and in others there were grains and fruits. We first observed the young animal get upon its feet and walk; then it shook itself, and afterwards scratched its side with one of its feet; then we saw it smelling to every one of those things that were set in the room, and when it had smelt to them all, it drank the milk.” Thereupon Galen and his friends cried out with admiration," seeing clearly," as he says, “ that the natures [actions] of animals come not from instruction,” but from instinct. He might also have said, that human actions of this class are equally untaught, for the infant readily accepts its proper food, while it loathes the nauseous medicine.
It is evident that the appetites are called instinctive only because they are not acquired by experience or instruction; they are innate. But this is far from being the only characteristic of what are usually termed the instincts of the lower animals, which often lead to complex and prolonged tasks, involving a constant sacrifice of their natural desires and inclinations. We place the more stress upon this point, because, as will be shown hereafter, if the name of instinct be denied to these original and simple preferences and aversions, there will appear good reason to doubt whether man is ever governed by instinct properly so called, whether all his actions are not reducible to passion, appetite, and reason. exist in the brute conjointly with a low degree of intelligence; but the intellect of man is pure and unmixed. It
be obscured by appetite, or stormed by passion; habit may render its operations so swift and easy, that we cannot note their succession ; but when free from these disturbing forces, it acts always with a full perception of the end in view, and by a deliberate choice of means aims at its accomplishment. Instinct is marvellous and inscrutable in its operations, as much so as reason itself. But that the appetites have their appropriate objects, and reject all others, is no special cause for wonder, any more than the fact that glass transmits light, while it is impervious to air. Such is its original constitution.
How may we describe instinct, then, as distinguished from
appetite on the one hand, and from reason on the other, as all three are motives or guides to action? It is an impulse conceived without instruction, and prior to all experience, to perform certain acts which are not needed for the immediate gratification of the agent, but are useful only as means for the attainment of some ulterior object ; and this object is usually one of preëminent utility or necessity, either for the preservation of the animal's own life, or for the continuance of its species. The former quality separates it from intelligence properly so called, which proceeds only by experience or instruction ; and the latter is its peculiar trait as distinguished from appetite, which in strictness uses no means at all, but looks only to ends.
Instances without number may be adduced to establish the existence of both these characteristic features of instinct. Chickens hatched by steam, which have never seen any older birds of the same species, perform all the duties of incubation and feeding their young as perfectly as if they had been the constant objects of Dame Partlet's care in their own callow infancy. Insects born only after the death of their parents still run the little cycle of their appointed tasks, and make provision for their own future progeny, which they are never to see, with as much labor and foresight as were exercised in preparing and storing their own cradles. In such cases, there is no opportunity for experience, and no source of instruction. Again, certain insects, governing for the moment their own appetites, which would lead them to devour their food as soon as found, store up in subterranean cells a provision for the coming winter, though as yet they have experienced only the warmth and abundance of summer and autumn. The moth with great care collects food of a kind which it never uses for itself, as a provision for its young when in the transition state. Other instances may be found to any extent in works on the several branches of zoology; but these are sufficient for our present purpose.
It is important to look rather at the great number of these unquestioned instances of true instinct, than at a few doubtful cases, in which it may seem difficult to determine whether the action is attributable to instinct or to reason. We may not be able to draw with mathematical precision the line where intelligence begins ; but there is no doubt that a multitude of cases lie far beyond that line, where we cannot hesitate for a moment in assigning them to their proper class. Some naturalists have shown great ingenuity to little purpose in the attempt to resolve into reason one or two instances of what had commonly been considered as instinct, without reflecting that by so doing they required a greater amount, or higher degree, of wisdom than could safely be attributed to a Solomon. One such instance as that of a duck, which had been hatched from an egg laid under a hen, taking to the water immediately after it was released from its shell, to the great consternation of its foster parent, is enough to upset Darwin's whole theory.
Another peculiarity of instinct, and one of the broadest grounds of distinction between it and reason, is that it is not susceptible of improvement or education. It is complete from the beginning ; it makes no progress either in the individual or the race. The bee, as soon after its disclosure from the pupa as its body is dried and its wings expanded, takes its part in the labors of the little commonwealth with as much apparent activity and efficiency as its elders. It collects honey and builds a cell as adroitly in the first as in the last hour of its existence. And so it is with the species; the internal economy of a hive was just as marvellous in the days of Aristotle and Virgil as in those of Huber. It is sometimes asserted, indeed, that the descendants of animals trained for domestic purposes show greater docility, and may more easily be taught to perform their required tasks, than individuals of the same species whose parents had remained in a wild or undisciplined state. The alleged fact is a very questionable one, and may very probably have arisen from the circumstance, that the training of the former class began at an earlier age than that of the latter. As the imitative principle exists to a greater or less degree in all quadrupeds and birds, the habits of their young must be affected to some extent, from the earliest period of their existence, by observation of the movements of the elder animals around them. If a wild colt could be taken from the prairies immediately after it was foaled, and placed at once in the stable or the pasture by the side of the domesticated animal, it would probably show as much docility as the proper offspring of that animal, while a very short experience of entire freedom with the wild herd might render it less tractable. But even if we were to give full credit to the story, it would prove nothing as to the No. 132.
nature of instinct, properly so called, which constitutes only a part of the mental constitution of animals. Some faculties they unquestionably possess in common with man, the imitative principle just alluded to being one of them.
It is important to observe, that the power of instinct in many cases quite transcends that of reason. If it differs from human intelligence not in kind, but in degree only, it is undoubtedly the superior. Man may go to school to the dog, the swallow, and the bee ; but however long a time he may remain there, he will never equal his teacher. Let him attempt, for instance, without the aid of any tools or machinery, and with the utmost possible economy of space and material, to construct a symmetrical hexagonal cell, closed at one end by a trihedral pyramid, each side of which is a rhombus, with its obtuse angles measuring precisely 109° 28', and its acute angles 70° 32. Without instruments or a pattern, he probably could not cut such a rhombus with perfect accuracy out of a piece of paper after a thousand trials
. But the bee does this before it is a day old. And in this statement of the task we have left out the greatest difficulty of all; we have solved the most abstruse problem'in it, so as to make its performance more easy. In order to make the cell with as little wax and space as possible, it is necessary that the angles of the rhombus should have precisely these dimensions and no other. It was only after the invention of the calculus that man was able to determine the angles required for this purpose, or, in other words, to discover how far the wisdom of the bee transcended his own. In Virgil's time, the bee was wiser than the greatest human mathematician of its day.
Those who are familiar with the habits of animals can produce a multitude of other instances to show the vast superiority of instinct, in its proper and limited sphere, to the best efforts of the human reason ; especially when we make the proper qualification, that the animal usually works without instruments of any kind, except those furnished in its own body, which affords nothing to be compared, in point of convenience, with the human hand. But we give one other case, which needs not this qualification ; it is found in the explanation of the proverbial phrase, “a bee-line.” Remove a man blindfold several miles from his home, by a route with which he is entirely unacquainted, and require