Every man has his own measure of reason, be it more or less. It is largely personal and original with him, and frequent failure is the penalty he pays for this gift.

But the individual beaver has only the inherited intelligence of his kind, with such slight addition as his experience may have given him. He learns to avoid traps, but he does not learn to improve upon his dam or lodge building, because he does not need to; they answer his purpose. If he had new and growing wants and aspirations like man, why, then he would no longer be a beaver. He reacts to outward conditions, where man reflects and takes thought of things. His reason, if we prefer to call it such, is practically inerrant. It is blind, inasmuch as it is unconscious, but it is sure, inasmuch as it is adequate. It is a part of living nature in a sense that man's is not. If it makes a mistake, it is such a mistake as nature makes when, for instance, a hen produces an egg within an egg, or an egg without a yolk, or when more seeds germinate in the soil than can grow into plants.

A lower animal's intelligence, I say, compared with man's is blind. It does not grasp the subject perceived as ours does. When instinct perceives an object, it reacts to it, or not, just as the object is, or is not, related to its needs of one kind or another. In many ways an animal is like a child. What comes first in the child is simple perception and memory and association of memories, and these make up the main sum of an animal's intelligence. The child goes on developing till it reaches the power of reflection and of generalization—a stage of mentality that the animal never attains to.

All animal life is specialized; each animal is an expert in its own line of work—the work of its tribe. Beavers do the work of beavers, they cut down trees and build dams, and all beavers do it alike and with the same degree of untaught skill. This is instinct, or unthinking nature.

Of a hot day a dog will often dig down to fresh earth to get cooler soil to lie on. Or he will go and lie in the creek. All dogs do these things. Now if the dog were seen to carry stones and sods to dam up the creek to make a deeper pool to lie in, then he would in a measure be imitating the beavers, and this, in the dog, could fairly be called an act of reason, because it is not a necessity of the conditions of his life; it would be of the nature of an afterthought.

All animals of a given species are wise in their own way, but not in the way of another species. The robin could not build the oriole's nest, nor the oriole build the robin's nor the swallow's. The cunning of the fox is not the cunning of the coon. The squirrel knows a good deal more about nuts than the rabbit does, but the rabbit would live where the squirrel would die. The muskrat and the beaver build lodges much alike, that is, with the entrance under water and an inner chamber above the water, and this because they are both water-animals with necessities much the same.

Now, the mark of reason is that it is endlessly adaptive, that it can apply itself to all kinds of problems, that it can adapt old means to new ends, or new means to old ends, and is capable of progressive development. It holds what it gets, and uses that as a fulcrum to get more. But this is not at all the way of animal instinct, which begins and ends as instinct and is non-progressive.

A large part of our own lives is instinctive and void of thought. We go instinctively toward the warmth and away from the cold. All our affections are instinctive, and do not wait upon the reason. Our affinities are as independent of our reflection as gravity is. Our inherited traits, the ties of race, the spirit of the times in which we live, the impressions of youth, of climate, of soil, of our surroundings,—all influence our acts and often determine them without any conscious exercise of judgment or reason on our part. Then habit is all-potent with us, temperament is potent, health and disease are potent. Indeed, the amount of conscious reason that an ordinary man uses in his life, compared with the great unreason or blind impulse and inborn tendency that impel him, is like his artificial lights, compared with the light of day—indispensable on special occasions, but a feeble matter, after all. Reason is an artificial light in the sense that it is not one with the light of nature, and in the sense that men possess it in varying degrees. The lower animals have only a gleam of it now and then. They are wise as the plants and trees are wise, and are guided by their inborn tendencies.

Is instinct resourceful? Can it meet new conditions? Can it solve a new problem? If so, how does it differ from free intelligence or judgment? I am inclined to think that up to a certain point instinct is resourceful. Thus a Western correspondent writes: "At three different times I have pursued the common jack-rabbit from a level field, when the rabbit, coming to a furrow that ran at right angles to his course, jumped into it, and crouching down, slowly crept away to the end of the furrow, when it jumped out and ran at full speed again." This is a good example of the resourcefulness of instinct—the instinct to escape from an enemy—an old problem met by taking advantage of an unusual opportunity. To run, to double, to crouch, to hide, are probably all reflex acts with certain animals when hunted. The bird when pursued by a hawk rushes to cover in a tree or a bush, or beneath some object. Last summer I saw a bald eagle pursuing a fish hawk that held a fish in its talons. The hawk had a long start of the eagle, and began mounting upward, screaming in protest or defiance as it mounted. The pirate circled far beneath it for a few minutes, and then, seeing how he was distanced, turned back toward the ocean, so that I did not witness the little drama in the air that I had so long wished to see.

A wounded wild duck suddenly develops much cunning in escaping from the gunner—swimming under water, hiding by the shore with only the end of the bill in the air, or diving and seizing upon some object at the bottom, where it sometimes remains till life is extinct.