Darwin for some reason constantly ignores the serviceability of expression as such—not so much as a fact, but as a principle—and hence its relation to natural selection, whereby he involves himself in needless difficulties. If an expression is of use, why should it not arise through natural selection as well as a limb, a wing, or an eye? Like other functions, expression may be incidental or may adapt variations attained originally for other ends, but in the case of the voice, at least, we have an original organ of expression as instrument of intercommunication.
Nor can I think Darwin’s treatment of the expressions of affection by the dog as due to antithesis a very happy or satisfactory solution. In the first place, the expression of friendliness by the dog is not the complete antithesis of that of hostility. The dog barks both out of friendly joy and from anger, as Darwin himself states. Some dogs also, as I have often observed in my dog, show pleasurable affection by wrinkling up the lips and showing the teeth, an act which is often mistaken for a hostile demonstration. Dogs also, as is the habit with my own, will often express affection in the same way as the cat (ibid., fig. 10), by rubbing against one. This is but an instance of a general law of expression of affectionate emotion, i.e., closeness of contact with the beloved object which is liked as promoting pleasure. This instinctive expression of love or liking certainly had its origin in serviceability, the appropriate effort toward the pleasure-giving thing or animal, but specially in the relation of parent and offspring, and in that of alliance in danger. Again, the tail of a hostile dog is, as figured by Darwin, straight and erect, but the opposite of this is the tail tucked between the legs when fleeing from pursuers in fear, rather than the position when showing friendliness to its master. My own opinion of the rise of the friendly expression of dog, cat, and other animals toward man is that they are in the main, at least, transferred from the serviceable friendly expressions used among themselves in a wild or domesticated state. I have repeatedly seen small dogs, who attach themselves to some large dog as their master, fawn, posture, and lick this master precisely as this master does his human master. Dogs and cats also show their affection and care for their offspring in many expressive acts which are transferred to their human owners. These expressions were primarily either directly serviceable actions, as the licking, or serviceable for expression as such, as various sounds made to give assurance of presence of food, or of safety. In general, it seems to me that when antithesis has occurred, it has arisen out of serviceability and not vice versâ.
With reference to the wagging of the tail in the dog, this is far from being an expression of affection alone. I have already mentioned the case of the setter where the movement of the tail is largely due to diffusion of superfluous energy, analogous to nervous habits like pacing the floor or biting the nails in human beings. With some dogs at least, as I have noticed in my own St. Bernard, the tail is switched slowly back and forth when approaching another dog with hostile intent. We have not as yet a sufficient number of facts at hand with reference to the history of the dog to pronounce the tail wagging as originating by virtue of its use as expression. And what is the rationale of the origin of the tail in the dog and cat, and for what reason has it been perpetuated? Is it a prehensile survival—which has been taken advantage of in the breeding of the pug—or is it a sexual characteristic, or did it originate to perform some directly advantageous action, as the tail of the cow and horse, or did it come into being as an organ of expression? Is the tail-wagging recognised by animals themselves as an expression as it is by man? These are questions on which we must have more data than we now possess in order to make any sufficient answers.
Again, the rise of the barking by dogs under domestication is another problem on which little can be said with certainty for lack of data. Darwin’s remark that it may arise by imitation of the loquacity of man seems to me ludicrously inadequate, and there seems no element of imitation in the noise produced. Domesticated animals in general tend to use the vocal organs for louder sounds than when in the wild state, for with wild animals the value of a loud noise as expression in any way is largely counterbalanced by its betraying presence to enemies. When natural enemies of the dog are driven out by man there will be a tendency toward a larger use of the vocal organs, both with reference to companion dogs and also to man. The particular sound, the bark, is determined by the nature of the whole vocal apparatus. The bark was, no doubt, originally to frighten aggressors, as I have often seen a large dog frighten a small dog from a piece of meat by a sudden resounding bark. Gradually attained as a mode of terrifying his competitive associates and certain game which it follows under domestication, and so preserved and developed by natural selection, the tendency is also powerfully strengthened by artificial selection, the best barker, other things being equal, being chosen for breeding by man. When the bark has become a common and habitual practice, it becomes a vent for superfluous energy developed by joy and other emotions. Like snarling or grinning, it is also a play form, and thus becomes denotative of joy by association. To impress one’s friendliness or hostility upon others, to appease or terrify, are the two main ends of expression with both man and animals, and this function is excited in various ways by different species, as determined by environment. The danger signal and the safety signal, the beware or welcome, is amplified and varied according to particular requirements which must be fully investigated before we can give any complete rationale of any expression. Conciliatory and menacing expressions and gestures have been evolved and matured in strict correlation under the same general law of natural selection, and neither one nor the other is due to antithesis. It is entirely unlikely that of such expressions, one, the hostility side, was first developed by natural selection, the other owing its rise to a distinct principle, antithesis.
However, I am not ready to deny antithesis all force as principle of expression, but it seems to me it should be ranged with law of similarity or analogy as subsidiary, and largely influential only in the higher types of expression, especially the teleologic human, as in gesture. Thus, if thumbs up means pity, thumbs down would naturally be used to denote pitilessness. To nod the head means assent or yes, to shake the head means dissent or no, though the exact antithesis would be to throw the head backward—assent signal with some tribes. However, while it may be asserted that, as a general law, that like emotions express themselves in like ways, unlike in unlike, this can hardly be used to throw much light on expression. Given a particular emotion and its expression, we can by no means deduce immediately the expression of the opposition emotion. Particular conditions and special organic limitations will always make this impracticable, and it is the office of the scientist to study expression in the course of evolution as of service under a multitude of conflicting interests and distracting difficulties.
We view expression then as mainly due to the principle of advantageous variation in the struggle for existence. Expression is the action required in the battle for life, or accompaniments to assist this action, or the call for aid to bring it about. Natural selection is the first and fundamental law of expression, negative expression and superfluous energy both being secondary and often pathologic in tendency.
The struggle for existence is itself on the very face of it an expression of mind, namely, activity significant of certain will and feeling experience. Whatever shows mind is expression, and thus in a large sense every movement in the physical universe—and what is the universe but motion—and every organic activity may be construed as expression. Whether all force, motion, action, is or must be expression is, however, a philosophic investigation which we need not now discuss, though we may suspect that the height and depth of mind and so the range of expression is enormously beyond the science of to-day. However, restricting ourselves to the domain of animal life, it is obviously very difficult to determine just what activities of a given organism betray mind, and still more just what form of mentality is manifesting itself. Man, being the measure of all things, interprets himself in all, and even when he becomes aware of the dangers of anthropomorphism he cannot wholly disengage himself from the tendency. The subjective analogical interpretation is a necessary evil. Still man is the keenest sighted of all beings for expression, and actions in a very wide range which had not in fact the real function of expression become expressive to him. The primary value of fear for the deer is to make it run from danger, and the running becomes expressive of the fear to observers, though the running is not for the expression. Thus vital activities of many kinds are expressive, though their primary value is not in the expression. Activities whose sole or main value is to give expression are comparatively late, the value of expression in this narrow sense being in the mental impression thereby made upon other organisms. Thus actions which serve purely to frighten others, in making one’s self formidable by loud noises, as roar of lion, bark of dog, by erecting the hair, displaying claws, teeth, and other such actions are pure expressions.
There is a constant growth in the value of expressiveness as we ascend the scale of life, expression playing a larger and larger part till with man certain individuals become specialized as expressionists, artists, poets, and orators. Further, fine art is expression which has its value, not in any exterior utility, but in itself alone, the subjective emotion seeking in a manner perfectly free from the common utilities of life to find itself a complete and perfect embodiment. Art here does not serve life, but life, art. The experience has in itself its own vindication for being, in that it expresses. Expression is no longer bare action nor yet a function to serve life, but it becomes a life in itself. In this ideal life of pure expression we recognise the necessity that the expressionist be emancipated from the struggle for existence, be freed from the sordid cares of life, and given up wholly to expressing his individuality with characteristic force; hence the State often pensions writers and artists. But apart from this ideal life, in the evolution of intricate sociality and industry and complex culture, expression becomes a more and more potent factor. Man in society must not only be, he must reveal himself, he must show what he is in order to achieve the most. Many fail, not for lack of faculty, but for lack of expressive ability. Expression, then, in general, is a function which, starting from the most minute beginnings in the lower animals, culminates in man. In large part man is man by reason of his superior power of expression, especially by speech, oral and written. Evolution in man is on the mental side in particular, but a large part of this mentality has been given to the improvement of expression in making it more facile, full and rapid. The complete natural history of expression is yet to be written, and all that I attempt is to indicate the point of view for such an investigation.
There are two points further with reference to expression which merit a few remarks. The first is as to the reaction of expression on emotion. We have treated to some extent the relation of emotion to its expression, but we have also to consider the relation of an expression to its emotion and to emotion in general. We have all along assumed that the emotion as a factor in the evolution of life is an internal stimulus to a serviceable activity, which may be viewed as its expression, or may even have its value as such. That emotion, as stimulus of action, determines expression is, I think, a primary law. However, Prof. James maintains (Mind, xxxiv., 188) the reverse—that expression determines the emotion.[[H]] We do not strike because we are angry, but we are angry because we strike. Hence, in reality, the emotion is really the expression, that is, the emotion is the consciousness result of the so-called expression—it expresses the “expression” in terms of consciousness. We commonly speak of expressing our emotions, but we should rather speak of emotions as expressions in consciousness of certain bodily activities. But if we make emotion but a psychological incident and off-shoot of certain activities, I take it we run directly counter to the general function of mind in evolution as internal stimulant to useful activity. Emotion is, I judge, fundamentally a motive force and has its function, and so its rise and development as such. It is more than a by-product, but even if it were, how should we account for it? After the serviceable activity has actually been brought about, after a man has really struck down his adversary, what is the utility of emotion? We take it that the value of emotion lies in starting and supporting the activity, and it is advantageous economy that it cease immediately on the accomplishment of its end. While we must always suppose that emotion has its physical support in central neutral changes, yet the expression is truly such; that is, it is from a different impulse as determined by the emotional brain excitement. In the light merely of a theory of natural selection, mind in general, and emotion in particular, is more than incidental concomitant of physical changes, more than echo of corporeality: it has a vital and central function in the evolution of life. Prof. James points to the fact that exercising the expressions or imagining the feeling calls up the feeling, as a proof of his theory. This, however, is merely a matter of association, and can prove neither a real precedent nor resultant. We may call up ideation as well as emotion by producing associated activities. In the interdependence of the conscious life, emotion, perception and willing call up each other without reference to causative order. Any one element of consciousness may be regarded either as resultant or stimulant, according as we look at preceding or following state of consciousness. In the order of evolution, pain and pleasure arise from certain actions in order to inhibit or stimulate repetition of actions. Feeling is then, both resultant and stimulant. The emotions may arise from the expressions by association, but the original dependence is that of expression on emotion. The further test, that we cannot imagine an emotion without bringing in bodily presentation, is simply a necessity of the imaging faculty as such, an image by its very nature being concrete.