THE EXPRESSION OF THE FACE

I

The eye examines the human countenance with such rapidity and such accuracy that no one will ever succeed in giving in words a picture of the minute details and fugitive traits which we see appear and disappear on the face during emotion. Even the greatest masters were not very exact in such-like descriptions, and had recourse to similes, to flowery and metaphorical language. If, for instance, we write that someone looked at us in astonishment or fear, we indicate an endless series of gradations of the same feeling, differing one and all from each other in intensity and effect, and we leave it to the judgment of the reader to choose that which seems to him best suited to the instance, without our having the means to demonstrate it to him. When we say to a friend, 'I must give you a piece of bad news,’ there appears a sudden change in his face, his look and his gestures, which touches us. But there is no art of words capable of describing it, because we cannot measure the imperceptible changes which take place in the movement of the eyes, the widening of the pupils, the colouring of the cheeks, the trembling of the lips, the dilatation of the nostrils, the acceleration of the breath, the gestures of the hands, the attitude of the head and trunk.

Certain fine characteristic traits of the face disappear under the magnifying glass like the diamond burning away in the crucible. The aspect of the countenance is impalpable; its beauties are covered by a subtile, delicate veil, which we cannot touch without tearing it and destroying the charm.

It is on this account that I stretch out my hand hesitatingly to take hold of the scalpel and lay bare the head of a corpse, in order to cut through the skin and detach the muscles. When I have separated the muscles of the face from the bones of the skull, a mask like a funnel of flesh remains in my hand. Oh, how ugly is the human face seen from the wrong side! We do not recognise ourselves; we cannot believe that this fibrous web and muscular network represent the most beautiful and expressive part of the organism; that this is the face formerly so graceful in its movements and play of feature, so inexhaustible in its expressions of benevolence and affection. It is a thorough disillusion, a sad sight, as when one sees the framework and the burnt-out rockets of fireworks in broad daylight, or when, at the end of the play, we examine near-to the daubs and rags of a dazzling theatrical decoration. We cannot believe that it is this fibrous flesh which lends us the aspect, the characteristic traits, the expression of our ego; that it is on this thin leaf of muscle that each writes his life-story; that it is the chance arrangement of these parts which impels us to mysterious sympathies, to indifference, antipathy, repugnance; that it is the unfathomable secret of these organs which unconsciously draws men together or apart, like atoms that meet, separate, or remain indissolubly united.

II

Leonardo da Vinci, who was certainly one of the greatest connoisseurs of the human countenance, had studied its anatomy with such ardour that the drawings of his preparations still excite the admiration of the learned by the accuracy of the most minute details.

'First study Science, and then follow her daughter Art', said Leonardo to his pupils; and these words are worthy of him who was not only a great artist and mathematician, and an illustrious philosopher, but who earned the title, far more difficult to acquire, of being an innovator in science, and one of the founders of the experimental method.

We must not begin the study of the face with that of the human anatomy. The web of muscles is so close, the direction of the fibres so intricate, that we are baffled unless we know the origin of these muscles in the lower animals, unless we investigate their office in simpler beings, and the modifications which they undergo on the zoological ladder.

The most important parts of the face are the apertures of the mouth and nostrils. These alone never disappear, however the form of the head may alter in different animals. The lips, nose, and chin may become unrecognisable, as in birds; the eye may become a mere point, as in the mole, or may disappear altogether as in certain animals living in caves; but the mouth always remains, because the alimentary canal is the most useful organ of the body. It appears even in animals that have neither heart nor lungs, and is formed like a funnel at its upper end. It is this end of the alimentary canal which we call the face. However grotesque such a mode of expression may seem, it is yet the expression of truth.

The development of the facial muscles is proportioned to the need of seizing prey and crushing the food. In frogs, fish, reptiles, birds, that swallow their food whole, one may say that the face is wanting; they have no expression except in the eye. In birds, the functions of the facial nerve are restricted to a little filament distributed to the cutaneous muscles of the neck, which produces that ruffling of the feathers and erection of the crest which is the characteristic expression of their feelings. The more complex the movements of seizing and devouring the prey become, the more complicated becomes the formation of the mouth. The lips must be mobile in order to suck the nipple of the breast, in the manner of a cupping-glass. Later, they serve to bring the fragments which must be masticated between the jaws, and further, they must be capable of being drawn upwards, as in the dog when he shows his teeth in preparing to bite.[18]

Then come the movements of the jaws furnished with fangs for tearing, crushing, breaking, gnawing, and again the very complex movements of the tongue in drinking, licking, collecting the food in the mouth, forming it into a bolus, and finally despatching it.

Of all animals, monkeys possess the greatest development of the facial muscles. This is owing principally to the circumstance that they eat everything, being half carnivorous, half herbivorous, and make use of the mouth as an organ for seizing the prey, and assisting the hands in tearing, skinning, and continually preparing the food.

The countenance of the monkey is of unexampled mobility; in a few minutes one sees all expressions pass over it, from desire to contempt, from cunning to innocence, from attention to carelessness, from love to rage, from aggression to fear, from joy to sadness.

III

One of the reasons why the facial muscles move more easily, is their diminutive size. It was Spencer who first clearly developed this idea, and I know of nothing more fundamental in the language of the emotions. 'Supposing,’ he says, 'a feeble wave of nervous excitement to be propagated uniformly throughout the nervous system, the part of it discharged on the muscles will show its effects most where the amount of inertia to be overcome is least. Muscles which are large, and which can show states of contraction into which they are thrown only by moving limbs or other heavy masses, will yield no signs; while small muscles, and those which can move without overcoming great resistances, will visibly respond to this feeble wave. Hence must result a certain general order in the excitation of the muscles, serving to mark the strength of the nervous discharge and of the feeling accompanying it.... It is because the muscles of the face are relatively small, and are attached to easily moved parts, that the face is so good an index of the amount of feeling.’[19]

This law, however, is in my opinion insufficient to explain the expressions of the face, because we have very fine, small muscles in the ear, the skin, and elsewhere, that yet take no part in the expression, although the resistance they offer is very small.

Great importance must, I think, be attached to the continual use of certain muscles, and to the different excitability of their nerves. The muscles which we most frequently put into movement are also those which most easily betray the excitement of the nerve-centres. It is so with the ear of the horse and dog, which is a faithful mirror of everything they feel, of all their emotions; while the ears of man, although possessing the same muscles, remain immovable even during the strongest emotion, and solely because we never make use of them.

The facial muscles are agitated by every little shock which the nervous system receives, because they are already perpetually in movement in respiration, speaking, chewing, and in the defence and use of the organs of sense situated in the head. We very often meet people who, in consequence of increased irritability of the nerve-centres, suffer from nervous contractions of the face, which make them wink rapidly, contort the mouth and frown, but we never notice similar disturbances in hands or feet, or in any other part of the body.

The varying resistance which the different nerves of the organism oppose to the nervous currents is an important factor in expression. The proximity of the muscles of the face, and especially of the eyes, to the brain renders the nervous discharges easier. Death always begins in the parts furthest removed from the centre, the legs grow rigid sooner than the arms, and the eye is the last to be extinguished.

The subject at present under consideration is a field of study which physiologists have perhaps too much neglected. Johannes MÜller,[20] the father of modern physiology, in speaking of those 'movements which depend upon mental conditions,’ expresses himself in the following manner: 'The extremely varied expression of the lineaments of the face in different passions, shows that, according to the various states of the mind, entirely different groups of fibres of the facial nerve are brought into activity. The reasons of this phenomenon, of these relations of the facial muscles to special passions, are totally unknown.’

Wishing to make a few experiments on the facial nerve, to see whether I should succeed in discovering anything in this obscure field of physiology, I laid bare the facial nerve, at its point of departure from the skull, in a dog rendered insensible with chloral, and then fixed two electrodes in such a manner that I was sure of being able to irritate the whole nerve by means of an electric current. While using irritants so weak that they were imperceptible on the tongue, I observed that they could cause a contraction of the muscles of the forehead and make the ears move, while the whole muzzle remained still as in an animal in an attentive attitude. When I used a slightly stronger stimulus, the muscles of the nose and eyelids and the zygomatic muscle moved; when the irritant was still more intensified, the muscles of the under-lip contracted and the mouth opened; while under very strong irritations, the dog assumed the fierce expression of one about to attack.

There is something fantastic in those experiments on decapitated animals of which the brain has been destroyed, and the face of which may be taken up in the hand like a mask of flesh. While applying an electric current to the motor nerves, one sees the features reanimate themselves, and a series of expressions pass over them one after another—attention, joy, rage, as though the electric apparatus applied to the facial nerve represented the commands of the brain or psychic impressions which in reality no longer exist.

The mechanical part of expression is, therefore, much simpler than one thinks. When a psychic operation takes place in the nerve-centres, the tension propagates itself along the nervous lines of least resistance. The more sensitive we are, the more graceful, beautiful, expressive, and fascinating is the curving of the lips produced by a smile. Peasants and coarse, dull persons cannot smile, with them the stimulus increases until it bursts out in a noisy, vacant laugh.

The nerve-paths are constructed in such a way that the brain does not need trouble itself about the muscular movements. It is the intensity of the excitement which produces the expression; the stronger it is, the more numerous are the paths through which the nervous tension forces its way; as it increases, it overcomes all obstacles and resistance confronting it in other paths impassable till that movement, and contracts muscles which till then had remained neutral.

The effects of the passions are reflected principally in the muscles of the face and respiration. No other function has to adapt itself more continuously than this last to the needs of the organism, standing as it does in close connection with all changes taking place in the nerve-centres. The muscles most vividly expressing passion are nearly all respiratory muscles.

IV

Our nervous system is so constituted that during violent emotion its activity discharges itself in all directions, and herein must we seek the reason of the resemblance between such different conditions as laughter and weeping, pain and pleasure.

It is the quantity, not the quality, of the stimulus which has weight on the scale of the expressions. This statement of mine will appear clearer if we study the phenomena produced by tickling.

When monkeys are touched in the arm-pit they twist and writhe, laugh, and emit sounds like human cries. The nerve-centres are very susceptible to the mechanical excitation of certain nerves, to contacts which fill us with the most pleasant and delicious sensations, or burst like a storm upon the organism.

We have heard of persons who let themselves be tickled to death, and there are many sensitive natures that can scarcely bear the most ardent enjoyments of life.

Here are prayers for pity, unconscious denials, entreaties in tearful tones, exclamations of astonishment, humble or clamorous voices, cries of joy or unsuppressed sighs, lamentations as of those who suffer, moans with which human nature seems to succumb.

Voluptuous enjoyment causes a vibration of the nerves, and forces from our lips the same moans as pain, which dulls the fire of life.

The respiratory movements are accelerated and panting, sometimes arrested, then recommencing irregularly; the breath pours stormily from the dilated nostrils, there is a singing in the ears, the heart beats more rapidly, and its pulsations resound with such violence that we wonder how a slight tickling of the nerves can produce such inward agitation.

The vital centres are stunned by a mysterious emotion—by a charm which deadens the senses and slackens the reins of control. With the cessation of the moderating force of the brain, the harmony of aim is destroyed, oppression seizes us, and words almost unconsciously spoken are now interrupted and repeated, anon breathless and drawn out, and are at last extinguished in the languor of a swoon. The dim eyes look upwards or hide moodily behind their lids, roll frightened in their orbits, or fill with tears of joy and close with the uncertain glance of the dying. The arms move convulsively, wildly, clutching, grasping, writhing. The teeth gnash and show themselves; there is a moaning and howling as though in man the animal soul had reawakened.

And at last, when the storm is past, the convulsions and trembling die away gradually like the flashes of lightning that follow the roar of retreating thunder. But the languid glance, the flaccid features, the moisture of the skin, the fatigue of the limbs, the spasmodic contractions of the muscles, the quivering of the voice, the thirst, the palpitation, the weakness, the lethargy of the senses, remain like the traces of a morbid paroxysm, like the depression after a great misfortune.