One of our well-known natural historians thinks that there is no difference between a man's reason and a beaver's reason because, he says, when a man builds a dam, he first looks the ground over, and after due deliberation decides upon his plan, and a beaver, he avers, does the same. But the difference is obvious. Beavers, under the same conditions, build the same kind of dams and lodges; and all beavers as a rule do the same. Instinct is uniform in its workings; it runs in a groove. Reason varies endlessly and makes endless mistakes. Men build various kinds of dams and in various kinds of places, with various kinds of material and for various kinds of uses. They exercise individual judgment, they invent new ways and seek new ends, and of course often fail.

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.

I once saw some farm-hands try to capture a fatted calf that had run all summer in a partly wooded field, till it had become rather wild. As the calf refused to be cornered, the farmer shot it with his rifle, but only inflicted a severe wound in the head. The calf then became as wild as a deer, and scaled fences in much the manner of the deer. When cornered, it turned and broke through the line in sheer desperation, and showed wonderful resources in eluding its pursuers. It coursed over the hills and gained the mountain, where it baffled its pursuers for two days before it was run down and caught. All such cases show the resources of instinct, the instinct of fear.

The skill of a bird in hiding its nest is very great, as is the cunning displayed in keeping the secret afterward. How careful it is not to betray the precious locality to the supposed enemy! Even the domestic turkey, when she hides her nest in the bush, if watched, approaches it by all manner of delays and indirections, and when she leaves it to feed, usually does so on the wing. I look upon these and kindred acts as exhibiting only the resourcefulness of instinct.

We are not to forget that the resourcefulness and flexibility of instinct which all animals show, some more and some less, is not reason, though it is doubtless the first step toward it. Out of it the conscious reason and intelligence of man probably have been evolved. I do not object to hearing this variability and plasticity of instinct called the twilight of mind or rudimentary mentality. It is that, or something like that. What I object to is hearing those things in animal life ascribed to reason that can be easier accounted for on the theory of instinct.

I must differ from the ornithologist of the New York ZoÖlogical Park when he says in a recent paper that a bird's affection for her young is not an instinct, an uncontrollable emotion, but I quite agree with him that it does not differ, in kind at least, from the emotion of the human mother. In both cases the affection is instinctive, and not a matter of reason, or forethought, or afterthought at all. The two affections differ in this: that one is brief and transient, and the other is deep and lasting. Under stress of circumstances the bird will abandon her helpless young, while the human mother will not. When the food supply fails, the lower animal will not share the last morsel with its young; its fierce hunger makes it forget them. During the cold, wet summer of 1903 a vast number of half-fledged birds—orioles, finches, warblers—perished in the nest, probably from scarcity of insect food and the neglect of the mothers to hover them. In interpreting the action of the animals, we so often do the thinking and reasoning ourselves which we attribute to them. Thus Mr. Beebe in the paper referred to says: "Birds have early learned to take clams or mussels in their beaks or claws at low tide and carry them out of the reach of the water, so that at the death of the mollusk, the relaxation of the adductor muscle would permit the shell to spring open and afford easy access to the inmate." No doubt the advancing tide would cause the bird to carry the shell-fish back out of the reach of the waves, where it might hope to get at its meat, but where it would be compelled to leave the shell unopened. But that the bird knew the fish would die there and that its shell would then open—it is in such particulars that the observer does the thinking.

Two other writers upon our birds have stated that pelicans will gather in flocks along the shore, and by manoeuvring and beating the water with their wings, will drive the fish into the shallows, where they easily capture them. Here again the observer thinks for the observed. The pelicans see the fish and pursue them, without any plan to corner them in shoal water, but the inevitable result is that they are so cornered and captured. The fish are foolish, but the pelicans are not wise. The wisdom here attributed to them is human wisdom and not animal wisdom. To observe the actions of the lower animals without reading our own thoughts into them is not an easy matter. Mr. Beebe thinks that when in early spring the peacock, in the ZoÖlogical Park, timidly erects its plumes before an unappreciative crow, it is merely practicing the art of showing off its gay plumes in anticipation of the time when it shall compete with its rivals before the females; in other words, that it is rehearsing its part. But I should say that the peacock struts before the crow or before spectators because it can't help it. The sexual instinct begins to flame up and master it. The fowl can no more control it than it can control its appetite for food. To practice beforehand is human. Animal practice takes the form of spontaneous play. The mock battles of two dogs or of other animals are not conscious practice on their part, but are play pure and simple, the same as human games, though their value as training is obvious enough.

Animals do not have general ideas; they receive impressions through their various senses, to which they respond. I recently read in manuscript a very clear and concise paper on the subject of animal thinking compared with that of man, in which the writer says: "There is a rudimentary abstraction before language. All the higher animals have general ideas of 'good-for-eating' and 'not-good-for-eating,' quite apart from any particular objects of which either of these qualities happens to be characteristic." It is at this point, I think, that the writer referred to goes wrong. The animal has no idea at all about what is good to eat and what is not good; it is guided entirely by its senses. It reacts to the stimuli that reach it through the sight or smell, usually the latter. There is no mental process at all in the matter, not the most rudimentary; there is simple reaction to stimuli, as strictly so as when we sneeze on taking snuff. Man alone has ideas of what is good to eat and what is not good. When a fox prowls about a farmhouse, he has no general idea that there are eatable things there, as the essayist above referred to alleges. He is simply following his nose; he smells something to which he responds. We think for him when we attribute to him general ideas of what he is likely to find at the farmhouse. But when a man goes to a restaurant, he follows an idea and not his nose, he compares the different viands in his mind, and often decides beforehand what he will have. There is no agreement in the two cases at all. If, when the bird chooses the site for its nest, or the chipmunk or the woodchuck the place for its hole, or the beaver the spot for its dam, we make these animals think, compare, weigh, we are simply putting ourselves in their place and making them do as we would do under like conditions.

Animal life parallels human life at many points, but it is in another plane. Something guides the lower animals, but it is not thought; something restrains them, but it is not judgment; they are provident without prudence; they are active without industry; they are skillful without practice; they are wise without knowledge; they are rational without reason; they are deceptive without guile. They cross seas without a compass, they return home without guidance, they communicate without language, their flocks act as a unit without signals or leaders. When they are joyful, they sing or they play; when they are distressed, they moan or they cry; when they are jealous, they bite or they claw, or they strike or they gore,—and yet I do not suppose they experience the emotions of joy or sorrow, or anger or love, as we do, because these feelings in them do not involve reflection, memory, and what we call the higher nature, as with us.

The animals do not have to consult the almanac to know when to migrate or to go into winter quarters. At a certain time in the fall, I see the newts all making for the marshes; at a certain time in the spring, I see them all returning to the woods again. At one place where I walk, I see them on the railroad track wandering up and down between the rails, trying to get across. I often lend them a hand. They know when and in what direction to go, but not in the way I should know under the same circumstances. I should have to learn or be told; they know instinctively. We marvel at what we call the wisdom of Nature, but how unlike our own! How blind, and yet in the end how sure! How wasteful, and yet how conserving! How helter-skelter she sows her seed, yet behold the forest or the flowery plain. Her springs leap out everywhere, yet how inevitably their waters find their way into streams, the streams into rivers, and the rivers to the sea. Nature is an engineer without science, and a builder without rules.

The animals follow the tides and the seasons; they find their own; the fittest and the luckiest survive; the struggle for life is sharp with them all; birds of a feather flock together; the young cowbirds reared by many different foster-parents all gather in flocks in the fall; they know their kind—at least, they are attracted by their kind.

A correspondent asks me if I do not think the minds of animals capable of improvement. Not in the strict sense. When we teach an animal anything, we make an impression upon its senses and repeat this impression over and over, till we establish a habit. We do not bring about any mental development as we do in the child; we mould and stamp its sense memory. It is like bending or compressing a vegetable growth till it takes a certain form.

The human animal sees through the trick, he comprehends it and does not need the endless repetition. When repetition has worn a path in our minds, then we, too, act automatically, or without conscious thought, as we do, for instance, in forming the letters when we write.

Wild animals are trained, but not educated. We multiply impressions upon them without adding to their store of knowledge, because they cannot evolve general ideas from these sense impressions. Here we reach their limitations. A bluebird or a robin will fight its reflected image in the window-pane of a darkened room day after day, and never master the delusion. It can take no step beyond the evidence of its senses—a hard step even for man to take. You may train your dog so that he will bound around you when he greets you without putting his feet upon you. But do you suppose the fond creature ever comes to know why you do not want his feet upon you? If he does, then he takes the step in general knowledge to which I have referred. Your cow, tethered by a long rope upon the lawn, learns many things about that rope and how to manage it that she did not know when she was first tied, but she can never know why she is tethered, or why she is not to crop the shrubbery, or paw up the turf, or reach the corn on the edge of the garden. This would imply general ideas or power of reflection. You might punish her until she was afraid to do any of these things, but you could never enlighten her on the subject. The rudest savage can, in a measure, be enlightened, he can be taught the reason why of things, but an animal cannot. We can make its impulses follow a rut, so to speak, but we cannot make them free and self-directing. Animals are the victims of habits inherited or acquired.

I was told of a fox that came nightly prowling about some deadfalls set for other game. The new-fallen snow each night showed the movements of the suspicious animal; it dared not approach nearer than several feet to the deadfalls. Then one day a red-shouldered hawk seized the bait in one of the traps, and was caught. That night a fox, presumably the same one, came and ate such parts of the body of the hawk as protruded from beneath the stone. Now, how did the fox know that the trap was sprung and was now harmless? Did not its act imply something more than instinct? We have the cunning and suspicion of the fox to start with; these are factors already in the problem that do not have to be accounted for. To the fox, as to the crow, anything that looks like design or a trap, anything that does not match with the haphazard look and general disarray of objects in nature, will put it on its guard. A deadfall is a contrivance that is not in keeping with the usual fortuitous disarray of sticks and stones in the fields and woods. The odor of the man's hand would also be there, and this of itself would put the fox on its guard. But a hawk or any other animal crushed by a stone, with part of its body protruding from beneath the stone, has quite a different air. It at least does not look threatening; the rock is not impending; the open jaws are closed. More than that, the smell of the man's hand would be less apparent, if not entirely absent. The fox drew no rational conclusions; its instinctive fear was allayed by the changed conditions of the trap. The hawk has not the fox's cunning, hence it fell an easy victim. I do not think that the cunning of the fox is any more akin to reason than is the power of smell of the hound that pursues him. Both are inborn, and are quite independent of experience. If a fox were deliberately to seek to elude the hound by running through a flock of sheep, or by following the bed of a shallow stream, or by taking to the public highway, then I think we should have to credit him with powers of reflection. It is true he often does all these things, but whether he does them by chance, or of set purpose, admits of doubt.

The cunning of a fox is as much a part of his inherited nature as is his fleetness of foot. All the more notable fur-bearing animals, as the fox, the beaver, the otter, have doubtless been persecuted by man and his savage ancestors for tens of thousands of years, and their suspicion of traps and lures, and their skill in eluding them, are the accumulated inheritance of ages.

In denying what we mean by thought or free intelligence to animals, an exception should undoubtedly be made in favor of the dog. I have else where said that the dog is almost a human product; he has been the companion of man so long, and has been so loved by him, that he has come to partake, in a measure at least, of his master's nature. If the dog does not at times think, reflect, he does something so like it that I can find no other name for it. Take so simple an incident as this, which is of common occurrence: A collie dog is going along the street in advance of its master's team. It comes to a point where the road forks; the dog takes, say, the road to the left and trots along it a few rods, and then, half turning, suddenly pauses and looks back at the team. Has he not been struck by the thought, "I do not know which way my master is going: I will wait and see"? If the dog in such cases does not reflect, what does he do? Can we find any other word for his act? To ask a question by word or deed involves some sort of a mental process, however rudimentary. Is there any other animal that would act as the collie did under like circumstances?

A Western physician writes me that he has on three different occasions seen his pointer dog behave as follows: He had pointed a flock of quail, that would not sit to be flushed, but kept running. Then the dog, without a word or sign from his master, made a long dÉtour to the right or to the left around the retreating birds, headed them off, and then slowly advanced, facing the gunner, till he came to a point again, with the quail in a position to be flushed. After crediting the instinct and the training of the dog to the full, such an act, I think, shows a degree of independent judgment. The dog had not been trained to do that particular thing, and took the initiative of his own accord.

Many authentic stories are told of cats which seem to show that they too have profited in the way of added intelligence by their long intercourse with man. A lady writing to me from New York makes the following discriminating remarks upon the cat:—

"It seems to me that the reason which you ascribe for the semi-humanizing of the dog, his long intercourse with man, might apply in some degree to the cat. But it is necessary to be very fond of cats in order to perceive their qualities. The dog is 'up in every one's face,' so to speak; always in evidence; always on deck. But the cat is a shy, reserved, exclusive creature. The dog is the humble friend, follower, imitator, and slave of man. He will lick the foot that kicks him. The cat, instead, will scratch. The dog begs for notice. The cat must be loved much and courted assiduously before she will blossom out and humanize under the atmosphere of affection. The dog seems to me to have the typical qualities of the negro, the cat of the Indian. She is indifferent to man, cares nothing for him unless he wins her by special and consistent kindness, and throughout her long domestication has kept her wild independence, and ability to forage for herself when turned loose, whether in forest or city street. It is when she is much loved and petted that her intelligence manifests itself, in such quiet ways that an indifferent observer will never notice them. But she always knows who is fond of her, and which member of the family is fondest of her."

The correspondent who had the experience with his pointer dog relates this incident about his blooded mare: A drove of horses were pasturing in a forty-acre lot. The horses had paired off, as horses usually do under such circumstances. The doctor's thoroughbred mare had paired with another mare that was totally blind, and had been so since a colt. Through the field "ran a little creek which could not well be crossed by the horses except at a bridge at one end." One day when the farmer went to salt the animals, they all came galloping over the bridge and up to the gate, except the blind one; she could not find the bridge, and remained on the other side, whinnying and stamping, while the others were getting their salt a quarter of a mile away. Presently the blooded mare suddenly left her salt, made her way through the herd, and went at a flying gallop down across the bridge to the blind animal. Then she turned and came back, followed by the blind one. The doctor is convinced that his mare deliberately went back to conduct her blind companion over the bridge and down to the salt-lick. But the act may be more simply explained. How could the mare have known her companion was blind? What could any horse know about such a disability? The only thing implied in the incident is the attachment of one animal for another. The mare heard her mate calling, probably in tones of excitement or distress, and she flew back to her. Finding her all right, she turned toward the salt again and was followed by her fellow. Instinct did it all.

My own observation of the wild creatures has revealed nothing so near to human thought and reflection as is seen in the cases of the collie and pointer dogs above referred to. The nearest to them of anything I can now recall is an incident related by an English writer, Mr. Kearton. In one of his books, Mr. Kearton relates how he has frequently fooled sitting birds with wooden eggs. He put his counterfeits, painted and marked like the originals, into the nests of the song thrush, the blackbird, and the grasshopper warbler, and in no case was the imposition detected. In the warbler's nest he placed dummy eggs twice the size of her own, and the bird proceeded to brood them without the slightest sign of suspicion that they were not of her own laying.

But when Mr. Kearton tried his counterfeits upon a ring plover, the fraud was detected. The plover hammered the shams with her bill "in the most skeptical fashion," and refused to sit down upon them. When two of the bird's own eggs were returned to the nest and left there with two wooden ones, the plover tried to throw out the shams, but failing to do this, "reluctantly sat down and covered good and bad alike."

Now, can the action of the plover in this case be explained on the theory of instinct alone? The bird could hardly have had such an experience before. It was offered a counterfeit, and it behaved much as you or I would have done under like conditions, although we have the general idea of counterfeits, which the plover could not have had. Of course, everything that pertains to the nest and eggs of a bird is very vital to it. The bird is wise about these things from instinct. Yet the other birds were easily fooled. We do not know how nearly perfect Mr. Kearton's imitation eggs were, but evidently there was some defect in them which arrested the bird's attention. If the incident does not show powers of reflection in the bird, it certainly shows keen powers of perception; and that birds, and indeed all animals, show varying degrees of this power, is a matter of common observation. I hesitate, therefore, to say that Mr. Kearton's plover showed anything more than very keen instincts. Among our own birds there is only one, so far as I know that detects the egg of the cowbird when it is laid in the bird's nest, and that is the yellow warbler. All the other birds accept it as their own, but this warbler detects the imposition, and proceeds to get rid of the strange egg by burying it under a new nest bottom.

Man is undoubtedly of animal origin. The road by which he has come out of the dim past lies through the lower animals. The germ and potentiality of all that he has become or can become was sleeping there in his humble origins. Of this I have no doubt. Yet I think we are justified in saying that the difference between animal intelligence and human reason is one of kind and not merely of degree. Flying and walking are both modes of locomotion, and yet may we not fairly say they differ in kind? Reason and instinct are both manifestations of intelligence, yet do they not belong to different planes? Intensify animal instinct ever so much, and you have not reached the plane of reason. The homing instinct of certain animals is far beyond any gift of the kind possessed by man, and yet it seems in no way akin to reason. Reason heeds the points of the compass and takes note of the topography of the country, but what can animals know of these things?

And yet I say the animal is father of the man. Without the lower orders, there could have been no higher. In my opinion, no miracle or special creation is required to account for man. The transformation of force, as of heat into light or electricity, is as great a leap and as mysterious as the transformation of animal intelligence into human reason.