Expression is then primarily all action connected with all consciousness, secondarily, it is useless action continued by force of habit and transmitted to descendants. But still many expressions are more than mere actions or their survivals. To be sure, Darwin and many Darwinists maintain that the expressions do not arise or exist for their own value as such, but they are entirely incidental. Expression is not the function of the so-called expressions, but they are entirely functional survivals. While, however, we must admit that many expressions have arisen and been preserved in this manner, yet I think it is altogether hasty to deny the function and value of expression per se. Expression has existed as a function from very early phases of life, and it underlies all bisexuality and sociality which have been such important elements in evolution. Organic sound-producing structures, whose sole utility from the very first is for attracting attention, early appear, and further voice seems to have its origin in the demand for love-call and call to young. Gregariousness is made possible in almost all its forms by purposive expression. There comes early, then, a will, not merely in performing some definite act at prompting of a feeling, but also a use in simply expressing it to others, communicating the fact of having pain or pleasure states to others. The cry of pain in young animals is a cry for help, and as such has been favoured in the struggle for existence. The usefulness of this action is solely as expression, and as expression it has arisen and been developed. Expression here is not an incidental view of a physiological action, but exists for its own value to the individual. Such expressions have their use in their significance, and as the true language of feeling are to be interpreted by the principle of serviceability. An expression which is and continues, by reason of its utility, as a sign-language, visual, auditory, or otherwise, as gesture love-calls, etc., may be termed pure expression as distinguished from incidental expression, like blushing, pallor, etc., which exist, not for their significance, though they are significant. Incidental expression includes also the sphere of degraded action. Yet what seems mere degraded action may be true expression, as beckoning, which is an abridgement of the action of pulling one to oneself and of movement towards oneself; but this motion of the hands exists, not for this end, nor as survival, but merely as significant of a desire on the part of the gesturer. In the higher ranges of life we well know the large place played by pure expression as distinguished from incidental expression. It is not necessary to suppose that pure expression consists merely in “voluntary and consciously” employing “means of communication” (Darwin, Expression of the Emotions, p. 256); thus, the scream of an infant is equally pure expression, whether the infant employs it knowingly or not as such, for screaming of the young has doubtless arisen and been preserved in natural selection because of its utility as significant. There is then, I think, a group of activities which are not merely incidentally expressive, but originate and exist for expression as a useful thing in the battle of life.
But we have not exhausted the principles of expression when we refer to present or past serviceability as an action in general or to service as expression. It is plain that in any activity prompted by any feeling there comes at a certain high intensity a more or less pathologic over-functioning of the organs concerned, with under-functioning of others. Emotion as action stimulator in any high degree always enhances some physiologic function to the depression of others. The blood, for instance, is forcibly withdrawn from various parts to certain specially active parts, and this withdrawal gives rise to an appearance which may be termed a negative expression, as the pallor in fear. Certain other phenomena connected with fear, as change of colour in the hair, cold sweat, and trembling of the muscles, which are mentioned by Darwin as unexplained, are probably due to this negative principle (Expression of the Emotions in Man and Animals, New York, 1886, p. 350[p. 350]; but compare pp. 81 and 308, where these disturbances are ascribed to direct action of the nervous system. Darwin does not, however, distinctly state or treat the principle we here mention as a distinct law). As the body is an inter-related system of organs, stimulation to one organ means an effect upon all, excitation of some, depression of others; thus to an acute observer the whole body is symptomatic of every feeling, and, indeed, of every consciousness. In the natural and normal course emotion, to do its work most effectively, implies little or no marked negative expression, but the nervous energy generated flows freely and directly to the organs which are to do service, without greatly impairing general function. Fear thus acts at first simply and advantageously; but in its later history fear becomes greatly complicated, and instead of freely issuing in serviceable action with not excessive heightening or depressing of any function, its outlet seems as it were choked, and the nervous energy spends itself within the body in violent disturbances of vital organs. Fear becomes then decadent and loses its place as evolutionary factor, becoming impediment rather than aid to progress. Negative expression must then be considered as especially notable in the later exhibitions of an emotion when concentration becomes morbid and ineffective, losing its advantageousness, and the emotion is being supplanted by other psychic factors. Great injury and death itself may result from the abnormal action of fear and other primarily useful psychoses.
Besides the particular organs to serviceable activity with the subsidiary physiological functioning, and the indirect depression, we must still note other principles which may control expression. Nervous energy under the incitement of emotion is often in excess of the demand for the required action, and it will then overflow into correlated activities along the line of least resistance. Also when the suitable action is checked for any reason, its motive force backs up and overflows in new channels. Indefinite and purposeless movements of various kinds thus result which may be expressive of the emotion of which they are incidentally the result. Any one who has watched an Irish setter tracing game must have remarked the wavings of the tail becoming more rapid when the scent becomes stronger. When the dog is running very fast, the tail-waggings are less noticeable than when moving slowly, although the interest may seemingly be the same in both cases. It is obvious that a fast run uses to a large extent the superfluous energy which was discharging in tail movements, and when the useful running is checked the tail motion recommences with greater force, serving as a safety-valve. The frisking of young animals and children is also largely due to diffusion of so-called superfluous nerve-force, and is expressive of general sensations of pleasure. All feeling is motor in its natural value and tendency, and unless the resulting energy is fully used in some special serviceable action, it will discharge itself along the easiest and most habitual lines laid down by inheritance. Thus the peculiar ancestral experience of animals is always expressed by their spontaneous diffusive activities. It will be remarked that the principle of diffusion is the reverse of negative expression, being an overflow of force as opposed to withdrawal. Excessive generation of energy is certainly uneconomical, and we must consider that at first emotion tended rather to less than the required amount, than more.
The phenomena of diffusive expression, in the strict sense, are thus rather late in appearance. The very lowest forms of life have no infancy or play period, and from the first are directly active in the struggle for existence. Yet the play period was certainly evolved through natural selection as a fully educative and preparatory stage, wherein the actions most demanded in actual life are unconsciously practised and a general basis of reserve force is accumulated. Play activity is a living on inherited energy and in the inherited modes: the kitten pouncing, the horse prancing, etc. Play is then rather a mode of activity than a mode of expression; it is expressive only in the way that all action is expressive. Expression proper is only in those modes of action which are carried on, whether consciously or unconsciously, by virtue of their significance value. If everything which is expressive is called an expression, we must include all the bodily actions and phenomena which can in any wise be connected with consciousness. I use the term diffusion in the narrow sense of spontaneous overflow of energy in excess of that absolutely required for the advantageous action. I do not refer to the general diffusion of emotional effect throughout the whole organism, which always occurs by the very nature of organism. Thus the pain from a pin-prick certainly modifies to some extent every cell in the body; there is a direct wave of influence from the psychic experience, and this is propagated throughout the whole organism by reason of its essential interdependency of parts; it echoes and re-echoes throughout the whole. The physiological result is then in simplest cases extremely complicated. However, this mere general fact of diffusion is a biological truism, and does not explain any expression, but simply asserts that every feeling, by virtue of its physical basis, affects the organism as a whole. Emotion issues specially in motor activities because its origin was as stimulant to necessary action, but this action involved internal organs, especially the circulatory and respiratory, and indirectly the whole body in every part. The explanation of an expression must always be in tracing back to the original serviceable actions with their demands on special subsidiary organs, and their depression of certain related organs, and not in reference to the general law of diffusion, which is but another term for the essential continuity of the organism. A useful principle of expression must not merely say that there is by the nature of organism a general bodily result from every emotion, but it must explain the particular expressions.
We make them so far four principles or forms of expression, which we instance in saying that the blow of an angry man is general activity expression, shaking the fist at one, purposive expression, scowling as remnant of watching foe intently in the open air is survival expression, and twitching and trembling of certain muscles is diffusive expression. Every emotion commonly issues in all four forms, in direct activity with associated survival tendencies and purposive expression, and a surplus of energy runs over into certain natural and easy motions, or a deficiency of energy in certain organs manifests itself, the negative side of diffusive expression.[[G]]
[G]. Since emotion comes in waves, expression is reduplicated. This may throw some light on such an expression as laughter. Landor says the Ainu do not in the proper sense laugh, but they roar with delight. It may be that laughter is reiterated roar as resulting from reiterated psychic impulses and feelings. As in the growth of an emotion, waves are multiplied, the expression becomes more reduplicate, and thus laughter tends to become more rippling and articulate. The cachinnation and explosiveness has thus a plausible explanation, which I merely suggest. At least Prof. Dewey’s explanation (Psychological Review, I., 559) that “both crying and laughing fall under the same principle of action—the termination of a period of effort”—is quite too general. Tension ceasing, effort stopped, we “breathe freely,” take deep inspirations. Laughter is far from being the usual outcome of such a status.
Darwin makes antithesis a principle of expression. Thus the expression of affection in the dog or cat toward its master cannot, says Darwin, be traced in any wise to serviceability, and we must seek its explanation merely as unconsciously and instinctively assumed as directly contrary to the serviceable hostile expressions. A dog’s expression of anger is, or has been, directly serviceable action, but the expressions of affectionate pleasure seem never to have had such an origin, but to have arisen merely as antithetic to the former, and so establishing the utmost distinctness of impression. To convey most clearly a motion of its friendliness the dog naturally assumes those attitudes which are most diverse from its expression of hostility. Their serviceability as expressions is best attained by being completely antithetical, and the more antithetical the better under natural selection. However, if this be the case, antithesis scarcely deserves, it seems to me, the name of a principle of expression, but it merely denominates the fact that opposite emotions in the struggle for existence tend to exhibit themselves in opposite ways as similar emotions in similar ways; but we need neither antithesis nor similarity as a principle. I believe that serviceability past or present either as direct action or as expression is the prime impetus of what we term the expression of the emotions, and I confess I do not see much force in Darwin’s Chapter on Antithesis. If, however, opposition has a meaning for life, as Darwin seems to imply, then does not the expression come under the law of serviceability? If there is any opposition in expression, I should explain this in general by utility rather than by antithesis per se. Thus take the gestures instanced by Darwin (ibid., p. 65), of pushing away with the hand when telling one to go away, and of pulling toward when telling one to come; these gestures are, indeed, antithetic, but their explanation does not lie in the fact of the antithesis, but in the fact of the past serviceable habit, by which individuals disliked or liked were repelled or attracted. In the present instance the person motioned to may be far beyond the reach of the arms, but still the gesture may be more than mere useless survival, for it acts as emphasis of the vocal expression, and has its influence there.