It is extremely doubtful, however, whether Bouvier is here using the term intelligence in its proper sense. Indeed, his words convey the impression that what he means by intelligence is an ability to profit by experience. Now, ability to profit by experience may, under one set of circumstances, involve the power of logical reflection and inference, while, under another set of circumstances, it may imply nothing more than the power of associative memory. In the latter case, the facts are explicable without any recourse to psychic powers of a superorganic nature, and, in point of fact, it often happens that the very zoöpsychologists, who insist on attributing this sort of “intelligence” to brutes, are most emphatic in denying that brutes are endowed with reason. In any case, it is unfortunate that the word intelligence is now used in two entirely different senses. This new and improper sense, being unrelated to the etymology, and out of harmony with the accepted use of the term, serves only to engender a confusion of ideas. It should be suppressed, in order to avoid misunderstandings.

That men should be deluded, however, into crediting animals with “intelligence” (properly so-called) is not at all surprising, when we reflect on the source of this misapprehension; for we find combined in the animal two important factors, whose association closely simulates intelligence, namely, sentient consciousness and unconscious teleology. Now teleology is not inherent or subjective intelligence, but rather an objective expression and product of intelligence. It exists in unconscious mechanisms like phonographs and adding machines, and it is, likewise, manifest in unconscious organisms like plants. Here, however, there is no danger of confounding it with conscious intelligence, because machines and plants do not possess consciousness in any form whatever. But in animals, on the contrary, teleology is intimately associated with sentient consciousness. Here the teleological automatisms of instinct are not wholly blind and mechanical, but are guided by sense-perception and associative memory. It is this combination of teleology with sentient “discernment” (as Fabre styles it) that conveys the illusory impression of a conscious intelligence. Careful analysis, however, of the facts, in conjunction with judicious experiments, will, in every instance, enable the observer to distinguish between this deceptive semblance of intelligence and that inherent rational power of abstraction, classification, and inference which is the unique prerogative of the human being. A genuine intelligence of this sort need not be invoked to explain any of the phenomena of brute psychology. All of them, from the highest to the lowest, are explicable in terms of the sensitivo-nervous functions. To illustrate the truth of this statement let us cite a few typical examples of animal behavior, that are sometimes regarded as manifestations of intelligent or rational consciousness on the part of the brute.

Animals, it is pointed out, learn by experience. The tiny chick that has been stung by a wasp, for instance, learns to avoid such noxious creatures for the future. This is, indeed, “learning by experience.” Obviously, however, it does not consist in an inference of a new truth from an old truth. On the contrary, it amounts to nothing more than a mere association of imagery, formed in accordance with the law of contiguity in time, sanctioned by the animal’s sensual appetite, and persistently conserved in its sentient memory. A bond of association is formed between the visual image of the wasp and the immediately ensuing sensation of pain. Thereafter the wasp and the pain are associated in a single complex, which the sensile memory of the animal permanently retains. We are dealing with a mere association of contiguity, and nothing further is required to explain the future avoidance of wasps by the chick. The abilities acquired by animals through the trial and error method are to be explained in the same way. A horse confined within an enclosure, for example, seeks egress to the fresh grass of the pasture. The fact that repeated exits through the gate of the enclosure have associated the image of its own access to the pasture with the particular spot where the gate is located induces it to approach the gate. Its quest, however, is balked by the fact that the gate is closed and latched. Thereupon, it begins to chafe under the urge of frustrated appetite. Certain actions ensue, some spontaneous and others merely reflex movements. It paws the ground, prances about, and rubs its nose against the gate. Its futile efforts to pass through the closed gate continue indefinitely and aimlessly, until, by some lucky accident, its nose happens to strike against the latch and lift it sufficiently to release the gate. This causes the gate to swing ajar, and the horse rushes out to food and freedom. By the law of contiguity, the vision of free egress through the gate is thereafter firmly associated in the horse’s sense-memory with the final sensation experienced in its nose just prior to the advent of the agreeable eventuation of its prolonged efforts. Henceforth the animal will be able to release itself from the enclosure by repeating the concatenated series of acts that memory associates with the pleasurable result. On the second occasion, however, the more remote of its futile acts will have been forgotten, and the process of opening the gate will occupy less time, though probably a certain amount of useless pawing and rubbing will still persist. Gradually, however, the number of inefficacious actions will diminish, until, after many repetitions of the experience, only those actions which directly issue in the desirable result will remain in the chain of impressions retained by memory, all others being eliminated. For, by a teleological law, making for economy of effort, all impressions not immediately and constantly connected with the gratification of animal appetites tend to be inhibited. Pawlow’s experiments on dogs show that impressions which coincide in time with such gratification tend to be recalled by a return of the appetitive impulse, but are soon disconnected from such association and inhibited, if they recur independently of the recurrence of gratification. For this reason, the horse tends to remember more vividly those actions which are more closely connected with the pleasurable result, and, as its superfluous actions are gradually suppressed by a protective process of inhibition, it gradually comes to run through the series of actions necessary to open the gate with considerable accuracy and dispatch.

The point to be noted, however, is that the horse does not discursively analyze this concatenated series of associated stimulators and actions; for, let the concrete circumstances be changed never so little, the horse will at once lose its laboriously acquired ability to open the gate. Such, for example, will be the result, if the position of the gate be transferred to another part of the enclosure. The horse, therefore, is incapable of adapting its acquired ability to new conditions. It can only rehearse the original series in all its initial concreteness and stereotyped specificity; and it must, whenever the circumstances are changed, begin once more at the beginning, and rearrive by trial and error at its former solution of the problem. The reason is that the horse merely senses, but does not understand, its own solution of the problem. The sense, however, cannot abstract from the here and now. Consequently, the human infant of two summers is enabled by its dawning intelligence to adapt old means to new ends, but the ten-year-old horse cannot adjust its abilities to the slightest change in the concrete conditions surrounding the original acquisition of a useful habit. The cognitive powers of an animal are confined to the sphere of concrete singularity, it has no power to abstract or generalize.

The selfsame observation applies to the tricks which animals “learn” through human training. Their sensitive memory is very receptive and retentive. Hence, by means of a judicious alternation of “rewards” and “penalties” (e.g. of sugar and the whip), a man can, as it were, inscribe his own thoughts on the tablets of the brute’s memory, in such a way as to force the latter to form habits that appear to rest upon a basis of intelligence. And so, indeed, they do, but the intelligence is that of the trainer and not that of the animal, which is as destitute of intrinsic intelligence as is a talking phonograph, upon whose records a man can inscribe his thoughts far more efficiently than he can write them in terms of the neurographic imagery of the canine, equine, or simian memory.

The trained monkey always renders back without change the original lesson imparted by its human trainer. The lesson as first received becomes an immutable reaction-basis for the future. With a school child, however, the case is quite different. It does, indeed, receive “an historical basis of reaction,” when the teacher illustrates the process of multiplication by means of an example on the blackboard. But it does not receive this information passively and render it back in the original stereotyped form. On the contrary, it analyzes the information received, and is able thereafter to reapply the analyzed information to new problems differing in specificity from the problem that the teacher originally worked out on the blackboard. The human pupil does not, like the monkey or the phonograph, render back what it has received in unaltered specificity. His reaction differs from its original passive basis. To borrow the words of Driesch, he “uses this basis, but he is not bound to it as it is. He dissolves the combined specificities that have created the basis.” (“The Problem of Individuality,” pp. 27, 28.) The brute, therefore, cannot “learn,” or “be taught” in the sense of intellectual comprehension and enlightenment. “We see,” says John Burroughs somewhere, “that the caged bird or beast does not reason because no strength of bar or wall can convince it that it cannot escape. It cannot be convinced because it has no faculties that are convinced by evidence. It continues to dash itself against the bars not until it is convinced, but until it is exhausted. Then slowly a new habit is formed, the cage habit. When we train an animal to do stunts, we do not teach it or enlighten it in any proper sense, but we compel it to form new habits.”

Human beings, however, can be taught and enlightened under the most adverse circumstances. Even those unfortunates are susceptible to it, who, like Laura Bridgman, Helen Keller, Martha Obrecht, Marie Heurtin, and others, have been blind and deaf and dumb from infancy or birth. With nearly all the light of sensibility extinguished, there was, nevertheless, latent within them something of which a perfectly normal ape, for all the integrity of its senses, is essentially destitute, namely, the superorganic power of reason. Reason, however, is extrinsically dependent on organic sensibility, and, consequently, “the gates of their souls” were closed to human converse, until such a time as the patient kindness and ingenuity of their educators devised means of reciprocal communication on a basis of tactile signals. Thereupon they revealed an intelligence perfectly akin to that of their rescuers. Years of similar education, however, would be futile in the case of an ape. The “gates of the soul” would never open, because the ape has no rational soul, to which the most ingenious trainer might gain access, in which respect it differs fundamentally from even the lowest savage. A being that lacks reason may be trained by means of instruction, but it can never be enlightened by it.

Another consideration, that is occasionally urged in proof of bestial intelligence, is the fact that birds, mammals, and even insects communicate with one another by means of sounds or equivalent signals, which are sometimes remarkably diversified in quality and consequent efficacy. “Since fowls,” writes Darwin, “give distinct warnings for danger on the ground, or in the sky, from hawks ..., may not some unusually wise ape-like animal have imitated the growl of a beast of prey, and thus told his fellow monkeys the nature of the expected danger? This would have been a first step in the formation of a language.” (“Descent of Man,” 2nd ed., ch. III, pp. 122, 123.) This is saltatory logic with a vengeance! Darwin leaps at one bound across the entire chasm between irrationality and rationality, without pausing to build even the semblance of a bridge. Given an animal with the foresight and inventiveness requisite to employ onomatopœia for the purpose of specifying the nature of an expected danger, in the interest of its fellows, and we need not trouble ourselves further about plausibleizing any transition; for so “unusually wise” an ape is already well across the gap that separates reason from unreason, and far on its way towards the performance of all the feats of which reason is capable. After swallowing the camel of so much progress, it would be straining at a gnat to deny such a paragon of simian genius the mere power of articulate speech. Of course, if imagination rather than logic, is to be the dominant consideration in science, there is no difficulty in imagining animals to be capable of thinking or doing anything we choose to ascribe to them, as witness Æsop’s Fables. But, if sober and critical judgment be in order, then, evidently, from the simple fact that an animal has diversified cries manifestative of different emotions or degrees of emotion (e.g. of fear or rage) and capable of arousing similar emotions in other animals of the same species, it by no means follows that such an irrational animal can adapt a means to an end by using mimicry in order to give notification of approaching danger, and to specify the nature of the danger in question.

This stupid anthropomorphism arises from Darwin’s failure to appreciate the fundamental distinction that exists between the “language” of animals, which is indicative, emotional, and inarticulate, and human language, which is descriptive, conceptual, and articulate. Brute animals, under the stress of a determinate passion or emotion, give vent impulsively and unpremeditatedly to instinctive cries indicative of their peculiar emotional state. Moreover, these emotionalized sounds are capable of arousing kindred emotions in the breasts of other animals of the same species, since organisms of the same species are syntonic with (i.e. attuned to) one another. Hence these reflex or instinctive cries have, no doubt, a teleological value, inasmuch as they serve to protect the race by inciting a peculiar flight-reaction in those that are not in immediate contact with the fear-inspiring object. This so-called warning, however, is given without reflection or intention on the part of the frightened animal, and is simply sensed, but not interpreted, by the other animals that receive it.

This premised, it is easy to discriminate between bestial and human language. The former is not articulate, that is to say, the sounds of which it is composed have not been elaborated by analysis and synthesis into phonetic elements and grammatical forms. In the second place, it is emotional and not conceptual, because it is manifestative of the emotions or passions (which are functions of the organic or sensual appetite), and not of rational concepts. In the third place, it is indicative, that is, it merely signalizes a determinate emotional state, as a thermometer indicates the temperature, or a barometer the atmospheric pressure. It is not, therefore, descriptive, in the sense of being selected and arranged in syntactic sequence for the express purpose of making others realize one’s own experiences. The rational language of man, on the contrary, is not emotional. Only a negligible portion of the human vocabulary is made up of emotional interjections. It consists, for the most part, of sounds descriptive of thought, to express which an elaborate system of vowels and consonants are discriminated and articulated on the basis of social agreement, the result being a conventional vocal code invented and used for the express purpose of conveying, not emotions or imagery, but general and abstract concepts.