CHAPTER III.

OCCASIONS AND CAUSES OF LAUGHTER.

It seemed desirable to examine the process of laughter itself before taking up the much-discussed question of its causes. In considering this side of our subject, we shall, as already hinted, take a comprehensive view of the occasions and modes of production of the mirthful outburst, and approach the narrower problem of the nature and mode of action of the ludicrous by way of this larger inquiry.

According to the common assumption, laughter, in ordinary cases, is excited by some provocative, to speak more precisely, by some sense-presentation, or its representative idea, such as a “funny” sensation, the sight of a droll human figure, or a quaint fancy. Yet we must not assume that such an initial presentation occurs in all cases. As is implied in what has been said above about the laughter of “good spirits,” and as we shall see more clearly presently, there are cases where laughter takes on the appearance of a spontaneous or “automatic” group of movements.

1. It may be well, however, to begin our inquiry by touching on those varieties of laughter in which the action of a sense-stimulus is apparent. And it will be convenient to select a form of distinctly provoked laughter in which the intellectual processes play only a subordinate part. The effect of tickling is clearly of this kind, and as one of the {51} simplest modes of exciting laughter it seems to claim our first attention here. Since, moreover, it is the mode of exciting laughter of which our knowledge has been rendered in a measure precise by means of experiment, I propose to deal with it at some length.

The experience of being tickled is best described in its entirety as a sensational reflex; that is to say, a motor reaction on a process of sensory stimulation which produces a well-marked variety of sensation. To speak of titillation as if it were merely the production of a certain kind of sensation is unscientific. It involves the excitation of certain movements, and where these are not forthcoming we must infer, either that the sensory part of the process is defective, or that the motor impulse is inhibited in some way.

The stimulation in this case is, as we all know, a light tactile one. The agent commonly applied is the finger or a still softer body, such as a feather. The mode of contact is light, or at least does not commonly rise to the point of heavy pressure. The manner of contact is usually intermittent, the finger or fingers giving a series of short and staccato impacts. Movements of the fingers from point to point commonly accompany the series of contacts. In some cases, however, a single light touch, or even a continuous touch with movement from point to point, may suffice to induce the proper effect.

The precise nature of the sensations is not yet fully understood. It is pretty clear that the “minimal stimuli” here employed do not give rise to purely tactile sensations of low intensity. This seems to be established by the fact brought out by Dr. Louis Robinson that the parts of the skin having the most acute tactile sensibility, the tips of the fingers and the tip of the tongue, are “scarcely at all sensitive {52} to titillation”.[30] It has been pointed out by Wundt that the sensations in this case, as in that of some other skin sensations, tend to spread themselves out, other and even distant parts of the surface being engaged by means of the mechanism of reflex sensation.[31] This in itself suggests that the sensations of tickling are more allied to organic than to purely tactile sensations. It is supposed that the light stimuli set up in the skin certain organic changes, more particularly modifications of the circulation of blood in the small vessels.[32]

It is well known that not all parts of the skin are equally susceptible of the effect of tickling. Certain areas, for example, the sole of the foot and the armpit, are commonly said to be “ticklish places”. In the answers to questions sent out by Dr. Stanley Hall we find the order, as determined by most frequent naming of the part, to be as follows: the sole of the foot, the armpit, the neck and part under the chin, the ribs, and so forth. The inquiries brought out the fact that there are considerable differences of experience here, some saying that they were ticklish in all parts, others only in one. The method adopted in this inquiry clearly affords no accurate measurement of comparative sensibility.[33] {53}

A more scientific attempt to measure this was made by Dr. Louis Robinson, who carried out a large number of experiments on children from two to four years of age with the definite purpose of testing the degree of responsiveness by way of laughter. According to his results the order of decreasing sensibility is as follows: (1) the region in front of the neck; (2) the ribs; (3) axillae; (4) bend of elbow; (5) junction of ribs and abdominal muscles; (6) flanks; (7) region of the hip joint; (8) upper anterior part of the thigh.[34]

A glance at these statements shows that the determination of the scale of ticklish sensibility over the surface is not yet completed. Dr. L. Robinson, by the way, mentions neither the sole, a highly ticklish spot in the popular creed, nor the palm, which, as we shall see, is decidedly a ticklish region.[35] It is highly desirable that more precise experimental inquiries should be directed to these local variations of ticklishness, and that, after the seats of the higher degrees of the sensibility have been ascertained, the question should be considered whether these are marked off by any definite peculiarities of structure.

It is probable that the sensations included under the head of ticklishness are not all of the same quality. It seems safe to say that in all cases the sensation is complex to this extent, that it is composed of a tactile and an organic factor. But we may see that the complexity is often greater than this. An obvious instance is the addition {54} of a peculiarly irritating effect when the orifice of the ear or nostril is tickled, an effect due to the action of the stimulus on the hairs, which are specially abundant here.[36] Some surfaces, too, which are free from hair, appear to be endowed with a special modification of the ticklish sensibility. In my own case, at any rate, light touches on the sole, have, as long as I can remember, excited sensations which seem to have almost a character of their own. A further complication probably occurs when the tickling grows rougher and approaches to a digging of the fingers into the soft parts of the armpits; for here the nerve-endings lying deeper are pretty certainly stimulated.

Lastly, it is important to add that prolongation of the tickling seems to introduce changes in the intensity, if not also in the quality of the sensations. Hence it would appear that the sensations falling under the head of ticklishness, though they have certain common characteristics, may vary considerably.

Since we are here concerned with these sensations as provocatives of laughter, it behoves us to look rather closely at their feeling-tones. As largely organic sensations they may be expected to have a strongly marked element of the agreeable or disagreeable; and this is what we find. I, at least, cannot conceive of myself as having the proper sensational experience of tickling, and yet being wholly indifferent.

When, however, we ask what is the precise feeling-tone of one of these sensations, we find no simple answer forthcoming. Some psychologists view them as having, in general, an unpleasant character.[37] On the other hand, children are {55} certainly fond of being tickled, ask for it, and make a pastime of it. This at once suggests that we have here to do with a complexity of feeling-tone, as, indeed, our study of the sensations would lead us to suppose.

It is, I think, a plausible supposition that no sensation coming under the head of tickling is merely agreeable or disagreeable. It seems always to be of a mixed feeling-tone: some sensational elements being pleasant, others unpleasant, though analysis may be unable to attribute with exactness their respective tones to the several elements.

Adopting this hypothesis, we should expect that the differences in the composition of the sensations already dealt with would lead to the result that, whereas some are preponderantly agreeable, others are rather disagreeable. And this, I believe, accords with the results of observation. The tickling sensations excited by stimulating the hairy orifices of the ear and the nostril are said by Dr. Louis Robinson to be “distinctly distasteful”. The sensations produced by tickling the sole of the foot are commonly held, at least by older children and adults, to be disagreeable in all degrees of their intensity. This certainly accords with my own self-observation. The lightest touch, say from a shampooer’s hand, is to me distinctly “nasty,” with an uncanny nastiness which I cannot hope to describe.

An example of a distinctly agreeable sensation of tickling is, curiously enough, supplied by another hairless surface, closely analogous to the sole, namely the palm. A lady, who is an excellent observer of children and endowed with an exceptional memory of her early experiences, tells me that when a child she loved to have her hands tickled. Her feeling was a kind of “awful joy,” the awfulness coming {56} from a vague suspicion that the pastime was not quite proper. Other preponderantly agreeable varieties appear to be the sensations produced by the lighter stimulation of those parts which seem in a special way to be laughter-provoking areas, _e.g._, the armpits and ribs. This is, at least, suggested by the fact that younger children love to be tickled in these parts in moderation, and will ask to have the pastime renewed.

An important characteristic of these feeling-tones is their unsteadiness or changefulness. Although at a particular moment we may be able to detect clearly a slight preponderance of the agreeable or of the disagreeable aspect, it is only for a moment. An increase in the degree of pressure, a further prolongation of the stimulation, or even a slight variation in the mode of contact, may suffice to bring up and render prominent the opposed feeling-phase.

We may now pass to the motor reactions, which are of more especial interest in the present connection. Overlooking the less conspicuous elements, such as the contraction of the muscles of the hairs, we find that there are two easily distinguishable groups of movements: (_a_) a number of protective or _defensive_ reactions which are adapted to warding off or escaping from the attack of the tickling stimulus; (_b_) movements expressive of pleasure and rollicking enjoyment, from the smile up to uproarious and prolonged laughter.

The defensive movements are such as the following:—retraction of the foot and leg when the sole is tickled; the bending of the head to the shoulder when the neck is tickled; the rendering of the body concave on the side which is attacked; the thrusting away of the hand of the tickler; wriggling and fencing with the arms when a child is tickled lying on his back. These movements appear to {57} introduce important modifications into the sensations excited by tickling. Dr. Louis Robinson tells us that the flexing of the foot when tickled transforms an unpleasant sensation into a rather pleasant one.

We may now pass to the point of chief importance for our present study, the conditions of the laughter-reaction during a process of tickling. This reaction is clearly the typical form of childish risibility.

It has been already more or less clearly implied, that we cannot mark off the laughter in this case as an effect determined by any assignable differences in the characteristics of the sensations involved. Dr. Louis Robinson thinks that the tickling which provokes laughter is a special variety involving the stimulation of the deeper-lying nerves. Dr. Leonard Hill, who has specially tested this point for me, writes, “There is no difference in response to deep and superficial tickling”; and again, “I am sure that the most delicate superficial stimulation can provoke laughter”. This certainly seems to agree with ordinary observation. One of the most laughter-provoking forms of tickling consists of a series of pianissimo touches.

Again, in speaking of ticklish areas of the skin, we must be careful not to restrict the titillation which calls forth laughter to any assignable region. It is undeniable that there are areas which more readily respond, in the case of children generally, to the tickling provocation. The armpits perhaps will occur to most readers; and it is noticeable that Darwin speaks of the anthropoid apes giving out “a reiterated sound, corresponding with our laughter, when they are tickled, especially under the armpits”.[38] This {58} fact, however, does not imply that the area of sensibility is circumscribed. Dr. Leonard Hill assures me, as a result of his investigations, that laughter under favourable conditions may be excited by tickling _any part_ of the body. Dr. L. Robinson in a letter explains to me that he agrees with Dr. L. Hill here. He finds that if a child is in a ticklish mood, the tickling of any part or even the threat of doing so will suffice to provoke laughter. On the other hand, we cannot speak of any part of the surface as one, the tickling of which will uniformly call forth laughter. Here again, as we shall see, the influence of mental agencies modifies the result.

Now these facts suggest that even those varieties of tickling which produce a sensation having a well-marked disagreeable tone may excite the response of laughter. The tickling of the sole of the foot not only provokes laughter in an infant; it tends to do so, I believe, in an adult, who may at the same time express his dislike of the sensation by a grimace.

It seems impossible then to conclude that the laughter which arises from tickling is a mere expression of the pleasure-tone of a sensational process. Even if we supposed that in all cases the sensations were preponderantly agreeable, it would still be impossible to account for the energy of the reaction by the intensity of the sensuous enjoyment experienced.

That we have not to do here merely with the effect of agreeable stimulation is shown by the fact that when a child laughs under, and is said to enjoy, a process of titillation, _the laughter is accompanied by defensive movements_. When, for example, a child is tickled on its back, it will, says Dr. Robinson, “wriggle about, fencing with its arms and dodging the attacks of its playmate . . . _laughing all the time_ {59} _with open mouth and teeth fully displayed_”. This surely suggests that the laughter is not merely the result of an agreeable sensation, but rather of a complex mental state, in which the agreeable and disagreeable elements of sensation appear to play only a secondary _rôle_.

Nor again does it seem as if the mere transition from an agreeable to a disagreeable sensation, or the reverse process, would account for the laughter of tickling. A person highly sensitive to the effect of tickling can imitate the process by movements of his own fingers, and produce quite similar sensations of varying feeling-tone _without experiencing the faintest impulse to laugh_. Again we know that other experiences, such as scratching a sore place when it is healing up, involve an alternation of moments of agreeable and disagreeable feeling-tone, and yet are not provocative of laughter.

These and other familiar facts point to the conclusion that the laughter excited by tickling is not a net effect of the sensory stimulation. It is no doubt broadly determined by the characteristics of the sensations. Intensely disagreeable ones would certainly not call forth the laughing response. But the determining conditions include, in addition to a sequence of sensations, _a higher psychical factor_, namely, an apperceptive process or assignment of _meaning_ to the sensations. This conclusion is borne out by the fact that the laughter-reaction occurs first of all (to give the earliest date) in the second month—presumably in the second half of this month. The presence of such a psychical factor is more strongly supported by the fact, already referred to, that the reaction does not occur in the first three months save when mental agencies co-operate; and that throughout the ticklish period an exactly similar process of titillative stimulation applied to the same area of the {60} skin will now produce laughter, now fail to do so, according to the varying mood of the child.[39]

That the interpretation of the sensation is the decisive element in eliciting laughter may, I think, be seen by a simple experiment which any reader who is ticklish may carry out upon himself. The next time he happens to have a subjective, creepy skin sensation, he will find that he can bring on either laughter or a very different state of feeling by adopting one of two ways of mentally envisaging what is happening. The merest suggestion of an invading parasite suffices, I believe, to set up a mental state which completely inhibits the impulse to laugh.

We may now seek to assign with more precision the mental conditions which induce the mode of apperception favourable to laughter.

Beginning with the “objective” characteristics, those which reside in the tickling experience itself, we may observe how much apprehension of meaning has to do with the “funniness” of the experience. It is to be noticed at the outset that when we are tickled there is _an element of the unknown_ in the process. This seems to have been recognised by Darwin when he laid emphasis on the fact that the more ticklish parts are those rarely touched, at least on small areas, and, one may add, lightly.[40] The familiar fact that one cannot tickle oneself points to the same conclusion. A person who tries to do this knows too much about what is going on. Dr. Ch. Richet observes, however, that one can tickle oneself _by means of a feather_; and he, as I think {61} rightly, explains this apparent exception by saying that in the attempt to tickle oneself with the finger, the double sensation, of the finger and the part tickled, seems to inhibit the effect, whereas, when the feather is interposed this obstacle is eliminated.[41]

Other facts, too, seem to point to the importance of an element of the unknown. The common way of tickling a child is by running the fingers with discontinuous contact over the skin. Dr. L. Hill describes his mode of tickling in one case as running the fingers up the child’s arm _like a mouse_. This evidently brings in an element of _local_ uncertainty as well as of change. The effect is increased when, as frequently happens, there are pauses between the attacks of the fingers.

The invasion of the skin-territory, like that of larger territories, is, it would seem, likely to be more effective when it has an element of unpredictableness. The uncertainty is, I believe, sometimes increased by half-voluntary variations in the direction and in the velocity of the tickling movements. Whether the fact communicated by Dr. L. Robinson, that a child is more ticklish when dressed than when undressed, is explained by the increased obscurity of the process in the former case, I am not sure. It is worth noting, however, that some of the areas said to be most ticklish, _e.g._, the armpits and the neck, are inaccessible to sight. I believe, too, that when a child gives himself up to the full excitement of tickling he makes no attempt to see what is going on.

Now touches of unknown origin at places not closely observable have something of a disturbing character. A touch is always an attack, and has, so to speak, to be {62} condoned. This disturbing element I regard as an essential element in the experience: it goes along with the faintly disagreeable element of sensation, which, as we have assumed, is commonly, if not always, more or less clearly recognisable in the experience.[42] Yet it is certain that the disturbing effect (like the disagreeableness of the sensation) is limited. If the unknown bulks too largely and comes near the point of the alarming, the effect of laughter is wholly counteracted. This is a part of the explanation of the refusal of a child to be tickled by a stranger: for he knows here _too little_ of what is going to happen, and consequently is disposed to fear. Again, Dr. L. Hill informs me that “tickling a child unexpectedly and from an unseen quarter will not provoke laughter”: the element of surprise would seem in this case to be too great. Possibly the comparative difficulty of making a child laugh when naked may be explained by the increased apprehensiveness which goes with the defenceless state of nudity. The familiar fact that the readiness to laugh increases with practice, points to the same need of a certain comfortable assurance lying safely below the slight superficial apprehensions which are excited by the stimuli.

All this suggests, that in order to call forth the glad response of laughter, we must secure a certain adjustment of stimulus to mental attitude. The tickling must fit in with a particular mood, the state of mind which makes enjoyment of fun not only possible but welcome.

Now it is clear that non-adjustment may arise, not only from the presence of unsuitable characteristics in the mode {63} of stimulation, but from some antagonistic force in the child’s previous state of mind. The acceptance of the attack in good part depends on the preceding attitude. The dreadfully serious, “on-the-alarm” attitude of the child when nursed by a stranger is an effectual bar to playful overtures. A child when cross will not, says Dr. L. Hill, give genial response, even if the attacker be his familiar tickler, father or nurse; and the same is true, he adds, of a child when suffering from vaccination, or when mentally preoccupied with some hurt for which he is seeking for sympathy, or with a story which he wants you to tell him. As Darwin puts it, the great subjective condition of the laughter of tickling is that the child’s mind be in “a pleasurable condition,” the state of mind which welcomes fun in all its forms. Possibly the position of lying on the back, which, according to Dr. L. Robinson, makes children more responsive to tickling, may, through a relaxation of the muscles, favour this compliant attitude of self-abandonment to the tickling fingers.

We may perhaps sum up the special conditions of the laughter-process under tickling as follows: when a child is tickled he is thrown into an attitude of indefinite expectancy. He is expecting contact, but cannot be sure of the exact moment or of the locality. This element of uncertainty would in itself develop the attitude into one of uneasiness and apprehensiveness; and this happens save when the child is happy and disposed to take things lightly and as play. In this case we may suppose that the half-developed mild form of fear is each time swiftly dissolved into nothing by a recognition of the unreality of the cause, of the fact that the touches are harmless and come from the good-natured mother or nurse by way of play. This recognition becomes clearer as the process is continued, and so there supervenes a new attitude, that of play, in which all {64} serious interpretation is abandoned and the gentle attacks are accepted as fun or make-believe.

If this is a correct analysis of the experience of the tickling which excites laughter, we seem to have in it at a very early age elements which are to be found, in a more fully developed form, in the later and more complex sorts of mirth, namely, relief from a serious and constrained attitude, a transition from a momentary apprehension induced by the presentation of the partially unknown, to a joyous sense of harmless make-believe. That this is so is further evidenced by the familiar fact that a child, when used to the game, will begin to laugh vigorously when you only threaten with the advancing fingers. As a German writer observes, this is a clear case of Lipps’ theory of annihilated expectation;[43] only he omits to note that the laughter depends, not on the mere fact of annihilation, but on the peculiar conditions of it in this case, involving a slight shock at the approach of something partially unknown to a specially sensitive region of the organism, and the instant correction of the apprehension by a recognition of its harmlessness.

Much the same kind of stimulative process seems to be present in the other and allied cases of reflex or quasi-reflex laughter. It is well known that certain sense-stimuli which excite sensations of a disagreeable character, but which, though acute, are not violent, such as the application of a cold douche, are apt to provoke laughter. According to the German authority just quoted, the effect depends here, too, on variation in respect of the intensity and the locality of the stimulation. He found further, in carrying out psychological experiments, that whereas the introduction of a stronger stimulus than was expected is apt to excite apprehension in {65} the subject, that of a weaker stimulus will excite laughter.[44] Here, too, we seem to have a sensational reflex in which is present a distinctly mental element, _viz._, a moment of mild shock and apprehension at the sudden coming of something disagreeable and partially unknown, instantly followed by another moment of dissolution of shock in a pleasurable recognition of the harmlessness of the assault.

2. Laughter is not, however, always of this reflex form. It may arise without sensory stimulation in an “automatic” manner as the result of a cerebral rather than of a peripheral process. This is illustrated by the seemingly causeless laughter which breaks out in certain abnormal states and has an “uncanny” aspect for the sane observer. A well-known example of this is the effect of the action on the brain centres of laughing gas and other substances. Such “automatisms” occur, however, within the limits of normal experience, as when a person laughs during a state of high emotional tension. I propose to speak of such seemingly uncaused reactions as _nervous laughter_.[45]

A common and simple variety of this nervous laughter is the spasmodic outburst that often succeeds a shock of fear. A child will laugh after being frightened by a dog; a woman often breaks out into a nervous laugh after a short but distinctly shaking experience of fear, _e.g._, in a carriage behind a runaway horse, or in a boat which has nearly capsized. And it does not seem that such laughter is preceded by a perception of the absurdity of the fear, or of any similar mode of consciousness; it looks like a kind of physiological reaction after the fear. {66}

The same thing will show itself in circumstances which give rise to a prolonged mental attitude, involving a feeling of apprehensiveness and of constraint. Thus a shy man, making his first essay as a public speaker, will sometimes betray his nervousness on the platform by weird little explosions of laughter as well as by awkward gestures. I have noted the same thing in strangers to whom I have spoken at a _table d’hôte_ abroad. The way in which little spasms of laughter are apt to intrude themselves into situations which, by making us the object of others’ special attention, bring an awkward consciousness of insecurity, is further illustrated in the behaviour of many boys and girls when summoned to an interview with the Head, in the laughter which often follows the going up to take a prize before a large assembly, and the like. The strong tendency to laugh which many persons experience during a solemn ceremony, say a church service, may sometimes illustrate the same effect. When an enforced attitude, difficult to maintain for the required length of time, brings on the impulse, this will gather strength from the growth of a feeling of apprehension lest we should not be equal to the test imposed.

Another variety, coming under the head of nervous laughter, is the sudden outburst which now and again occurs in a state of great emotional strain, having a distinctly painful character, especially when it includes something in the nature of a shock. The news of the death of an acquaintance has been known to excite a paroxysm of laughter in a company of young persons from nineteen to twenty-four years of age.[46] One may assume here that the {67} outbreak is not the direct result of the news, but depends on the effect of the shock, with the abnormal cerebral tension which this involves.

A like spasmodic outburst of laughter occasionally occurs during a more prolonged state of painful emotional excitement. It sometimes intrudes itself into a bout of physical suffering. Lange speaks of a young man who, when treated for ulceration of the tongue by a very painful caustic, regularly broke out into violent laughter when the pain reached its maximum.[47] Many persons when thrown into a prolonged state of grief, accompanied by weeping, exhibit a tendency to break out into laughter towards the end of the fit. Shakespeare illustrates this tendency when he makes Titus Andronicus, whose hand has been cut off, answer the question why he laughed with the exclamation: “Why I have not another tear to shed”.[48]

Can we find a common element in these different forms of nervous or apparently unmotived laughter? We appear to have in all of them a preceding state of consciousness which is exceptionally intense and concentrated. The situation of fear, of constraint on being made the object of others’ unusual observation, of suddenly hearing news of deep import for which the mind is not prepared, of prolonged emotional agitation, these all involve an intensification of the psycho-physical processes which immediately condition our states of consciousness. Looking at these intensified {68} forms of consciousness more closely, we observe that they include something in the nature of psychical pressure, of the presence of forces which make for disorder, whereas the situation calls for severe self-control. This special strain thrown on the volitional process is illustrated in the demand for closer observation and calm reflection during a fit of fear, or other emotional excitement, which tends to bring about a state of wild movement and of disorderly ideas. It is, I believe, _the specially severe strain_ belonging to such an attitude which is the essential pre-condition of the laughter. It makes the attitude a highly artificial one, and one which it is exceedingly difficult to maintain for a long period. As such, the attitude is eminently unstable, and tends, so to say, to break down of itself; and will certainly collapse, partially at least, if the demand seems, though only for a moment, to grow less imperative. Hence the readiness with which such a means of temporary relief as laughter undoubtedly supplies is seized at the moment.

It remains to determine the character of this sudden relaxation of the strain of attention more precisely. As a sudden collapse, it is clearly to be distinguished from the gradual breakdown due to “mental fatigue” and nervous exhaustion. The psycho-physical energy concentrated for the special purpose of meeting the strain is by no means used up, but has to find some way of escape. Here, no doubt, we seem to come across Mr. Spencer’s ingenious idea that laughter is an escape of nervous energy which has suddenly been set free. It is no less evident that the redundant energy follows the direction of the risible muscles because no other commanding object for the attention presents itself at the moment. The innervation of these muscles is not a mere diversion of attention: it is a _dispersion_ of the energies which for the maintenance of attention ought to {69} be concentrated. We are never less attentive during our waking life than at the moment of laughter. Yet even here, I think, the theory of a convenient waste-pipe arrangement is not adequate. There is, I take it, in the case a relief of sur-charged nerve-centres, which process would seem to be better described by the figure of a safety-valve arrangement.

It is not difficult to surmise why the liberated energy should follow this particular nervous route. There is no doubt that the motor apparatus, by the disturbances of which all such interruptions of the smooth flow of respiration are brought about, is very readily acted on by emotional agencies. Altered respiration, showing itself in altered vocalisation, is one of the first of the commonly recognised signs of emotional agitation; and this effect has been rendered more clear and precise by recent experiments. We should expect, then, that the collapse of strained attitudes, with the great change in feeling-tone which this must carry with it, would deeply affect the respiration. We know, however, more than this. Severe efforts of attention are in general accompanied by a partial checking of respiration, an effect which seems to be alluded to in the French expression, an effort “de longue haleine”. On the other hand, the termination of such an effort is apt to be announced by the sigh of relief. Now, though the movements of laughter are not the same as those of sighing, they resemble the latter in their initial stage, that of deepened inspiration. May we not conclude, then, that laughter is likely to occur as another mode of physiological relief from the attitude of mental strain? And supposing, as seems certain, that laughter in its moderate degrees, by bringing a new briskness into the circulation, relieves the congested capillaries of the brain, may we not go farther and say that nature has {70} probably come to our aid by connecting with the mental upheavals and the cruel strains here referred to, which pretty certainly involve a risky condition of the cerebral system of capillaries, a mode of muscular reaction which is peculiarly well fitted to bring the needed relief?

More special conditions may favour the movements of laughter in certain cases. As I have observed above, Darwin suggests that the rapid alternation of crying and laughing which occur among hysterical patients may be favoured by “the close similarity of the spasmodic movements”.[49] In other words, the motor centres engaged, when in the full swing of one mode of action, may readily pass to the other and partially similar action. This would help to account for the short outbursts of laughter during a prolonged state of painful agitation, and to explain the fact noted by Descartes, that no cause so readily disposes us to laughter as a feeling of sadness.[50]

Our theory plainly requires that these sudden breakdowns or relaxations of strained mental attitudes should, even when only momentary interruptions, be accompanied by an agreeable sense of relief. I believe that those whose experience best qualifies them to judge will say that this is so. The dead weight of the fear, the poignancy of the grief, and the constraining effect of the situation of _gêne_, seem to yield at the moment when the “awful laugh” is snatched at. This comforting sense of a lightened load, though in part the direct result of a cessation of cerebral strain, would, as we have seen, pretty certainly derive added volume from the returning sense-reports telling of the ameliorated condition of the bodily organs.

3. We have considered two of the varieties of laughter {71} which lie outside the region of our everyday mirth. We may now pass into this region, and inquire, first of all, into the causes of those varieties which come under the head of joyous laughter.

Here we shall best begin by touching on the simple and early form which may be called the overflow of good spirits. Darwin, as has been mentioned, rightly regards the full reaction of the laugh as the universal expression by our species of good spirits, of a joyous state of mind. We have now to examine the mode of production of this simple type.

It is important to note that all experiences of pleasure do not bring on laughter. There are quiet enjoyments of a soothing character which are far from generating the powerful impulse needed for the movements of diaphragm and rib. To lie on a summer day in a hammock in a wood and indulge in the sweets of _dolce far niente_ is to be out of reach of the tickling imp. States of enjoyment, too, which, though exciting, require a measure of close attention, such as those occasioned by a glorious sunset, or stirring music, do not start the spasmodic contractions of muscle.

The enjoyment that moves us to laughter must, it is evident, amount to gladness or joy. And this means, first of all, that the pleasurable consciousness must come in the form of a large accession, and, for a moment at least, be ample, filling soul and body. As the expression “good spirits” suggests, the organic processes during such states of joyousness are voluminous and well marked. As a part of this heightened tide of vital activity, we have the characteristic motor expression of the gladsome mind, the movement of the limbs, the shouting and the laughing.

Not all risings of the vital tide, however, produce laughter. Gentle and gradual augmentations of the sense of well-being {72} and happiness hardly tend to stir the muscles concerned. The joyous outburst marks a _sudden_ accession of happy consciousness. It has something of the character of a violent flooding of the spirit and the corresponding bodily conduits.

There is a negative condition, also, to which it may not be superfluous to allude. The flood-like rise of the happy mood which is to produce laughter must not be accompanied by any further demand on the attention. A girl reading a first love letter from the man whom her heart has chosen will be glad, and will grow gladder by leaps and bounds. But the fulness of laughter will not come while unread words still claim the eye.

The laughter of joy is most noticeable, I think, under two sets of conditions. Of these the first is the situation of release from external restraint. The wild jubilant gladness of boys as they rush out of school, provided that they have the requisite reserve fund of animal spirits, is the stock example of this sort of laughter. The explosion seems here to be a way of throwing off the constraint and the dulness of the classroom, and getting a deep breath of the delicious sense of restored liberty. So far as the outflow of good spirits is thus connected with an escape from a serious and difficult attitude—strenuous application of the energies of mind and body in work—it is plainly analogous to the nervous laughter already considered.

But the swift accession of joy may come in another way, from the sudden transformation of one’s world, from the arrival of some good thing which is at once unexpected and big enough to lift us to a higher level of happiness. With children and savages the sight of a new and pretty toy is sometimes enough to effect this. The charming bauble will so fill sense and soul that the joy of living leaps to a {73} higher plane and bursts into a peal of mirth. The unexpected sound of the father’s voice at the end of a long day devoted to the things of the nursery was, we are told, enough to evoke a shout of laughter in a small American boy: it sufficed to bring back to the little fellow’s consciousness another and a glorious world. We older folk have, for the greater part, lost the capacity of simply greeting delightful things in this way, a greeting in which there is no thought either of their meaning or of their interest for us. Yet we may meet the unexpected coming of friends with something of the child’s simplicity of attitude. It is hard not to smile on suddenly seeing a friend in a crowded London street: hard to keep the smile from swelling into a laugh, if the friend has been supposed at the moment of encounter to be many miles away. Some of us, indeed, may retain the child’s capacity of laughing with a joyous wonder at a brilliant explosion of fireworks.

It remains to account for the persistent fit of laughter which frequently accompanies a prolonged gladness. Does not the fact that the child and the natural man, when taken with the mood of mirth, go on venting their good spirits in renewed peals tell against our theory that the outburst is caused by an accession of joy?

In order to answer this we must look a little more closely at this so-called persistent laughter. The language of observers of unsophisticated human nature is sadly wanting in precision here. When, for example, we are told by travellers that certain savages are always laughing, we know that we are not to take the statement literally. It means only what it means when a mother tells her visitor that her rogue of a boy is for ever laughing and shouting; that under certain favourable conditions the laughing fit comes readily and persists longer than usual. In a lasting {74} mood of jollity we are all strongly inclined to laugh, and need very little to call forth a long outburst.

This preternaturally large output of laughter during a prolonged state of high spirits finds its explanation in part in a kind of physiological inertia, the tendency to go on repeating movements when once these are started. The protracted iteration of laughter in a child is closely analogous to that of his half-unconscious singing to himself. This tendency of movements to perpetuate themselves in a mechanical way probably accounts for the lengthening of the single outburst in the case of a child violently seized with mirth. As mothers know, this reduction of laughter to a mechanical iteration of movement is apt to continue beyond the limits of fatigue and to bring on such unpleasant effects as “hiccup”. It is probable, too, that the tendency during a prolonged state of mirth to recommence laughing after a short pause is referrible to a like cause: the physiological springs of the movements being once set going, the explosive fit tends to renew itself.

Discounting this effect of physiological inertia, we seem to find that in these periods of prolonged high spirits laughter retains its fundamental character as a comparatively short process which occurs intermittently. Where the laughing is not merely a trick played off by the bodily mechanism, but holds a germ of mind in the shape of a happy consciousness, it has its large and significant pauses.

If this is so, it seems reasonable to suppose that the mental antecedent which brings on some new explosion is analogous to the sense of “sudden glory” which accounts for the single joyous peal. Owing to the exceptionally strong disposition to laugh during such a period, the antecedent feeling need not be a powerful one, a very slight {75} momentary increase of the joyous tone sufficing to give a fresh start to the muscles.

It is not difficult to suggest possible sources of such slight sudden augmentations of the happy feeling-tone. No prolonged state of consciousness is, strictly speaking, of one uniform colour; in the boisterous merriment of an old-fashioned dinner-party there were alternations of tone, brilliant moments following others of comparative dulness. The course of the bodily sensations in these prolonged states of joy is in itself a series of changes, involving a sequence of exaltations upon relative depressions of the “vital sense”. The course of the presentations to eye and to ear in such a festive mood must be subject to like fluctuations in respect of their action upon the feeling-tone; and the same applies to the flow of ideas which can find a place in the mind when thus affected. Lastly, it must not be forgotten that the movements of attention would of themselves always secure a certain rise and fall of enjoyment. We all know how, when we are gladdened by some new and unexpected happiness, the mind after a short digression returns to the delightful theme, and how, as a result of this return, a new wave of joyous feeling seems to inundate the spirit.

There seems much, then, to be said for the hypothesis that all varieties of joyous laughter (when not reduced to a mechanical form) are excited by something in the nature of _a sudden accession of pleasurable consciousness_. Where the laugh is a new thing, unprepared for by a previous mood of hilarity, this rise of the spirits will, as we shall see later, probably involve a transition from a mental state which was relatively depressed. Where, on the other hand, a joyous mood prolongs itself, all that seems needed for re-exciting the movements of laughter (provided that the muscular {76} energies are equal to the explosion) is the sudden increase by an appreciable quantity of the pleasurable tone of the consciousness.

We may further illustrate and verify this generalisation respecting the causes of joyous laughter by an examination of some of the more familiar circumstances in which this is wont to occur. Here we shall of course be dealing with the early and unsophisticated mind. Properly drilled “grown-ups” but rarely exhibit the phenomenon in its full intensity.

(_a_) It is a matter of common observation that joyous laughter is a frequent concomitant of the play-attitude, especially at its first resumption. We have already found this illustrated in the laughter of “happy boys” just liberated from school. Here the conditions indicated, a relief from restraint and a sudden expansion of joyous activity, are patent to all.

Closely related to this situation of released bodily energies is that of relieved mental restraint. During a nursery lesson—if only the teacher is a fond mother or other manageable person—the child is apt to try modes of escape from the irksomeness by diverting the talk, and especially by introducing “funny” topics; and the execution of the bold little manœuvre is frequently announced by a laugh. By such familiar infantile artifices the pressure is lightened for a moment, and the laugh announces a moment’s escape into the delicious world of fun and make-believe.

The impulse to be gay and to laugh runs, moreover, through the enjoyment of play. No doubt this in its turn may often grow exceedingly serious, as when the illness of dolly, or the thrilling horrors of a bear’s cave, or of an attack by scalping Indians, are realistically lived out. Yet we must remember that this playful tampering with {77} the serious, even on its genuine side, is a part of the enjoyment. The momentary terror is desired by healthy young nerves, because the thrill of it, when the certainty of the nothingness lies securely within mental reach, is delicious excitement. A fuller examination of the relation of laughter to play belongs to a later stage of our inquiry.

(_b_) Another situation which is closely related to play is that of being teased. By “teasing” is here understood those varieties of attack which have in them an element of pretence, and do not cross the boundary line of serious intention to annoy. As thus defined, teasing enters into a good deal of child’s play. Tickling is clearly only a special modification of the teasing impulse. In some of the earliest nursery play, the game of bo-peep, for instance, there is an element of teasing in the pretence to alarm by a feigned disappearance, as also in the shock of the sudden reappearance. The teaser of a child, whether he threatens to pinch him or to snatch at his toy, carries out a menace; but it is a make-believe menace—a thing to be a wee bit afraid of for just a moment, yet so light and passing as to bring instantly the delightful rebound of disillusion, if only the subject keeps good tempered. On the teaser’s side (when it remains pure teasing) it is prompted by no serious desire to torment, by no motive more serious than the half-scientific curiosity to see how the subject of the experiment will take it.

The explosions of a good-humoured subject under such gentle teasing are closely analogous to those of a tickled child: they spring from a sudden sense of relief, of elastic rebound, after repression. The swift alternations of moments of nascent fear and of joyous recognition of the fun of the thing are eminently fitted to supply the conditions of a sudden rising of the spirits. The child that likes to be {78} teased—in the proper way of course—is perfectly willing to pay for these momentary delights by the momentary trepidations.

On the side of the teaser, the situation is also highly favourable to outbreaks of hilarity. If successful, he reaps the joy of the superior person, and glories in the cleverness of his experiments. The swellings of the sense of power as he watches his victim give just those experiences of “sudden glory” which a philosopher places at the base of all enjoyment of the laughable; and, alas, in the less kindly these risings of the pleasurable consciousness may continue and even increase after the teasing has ceased to be play and becomes indistinguishable from the behaviour of a tormentor.[51]

(_c_) Much the same kind of remark applies to practical joking, which, when it is not weighted with the serious purposes of punishment and moral correction, is merely an expansion of this playful attack of the tickler and the teaser. When the victim reaches the moral height of being able to enjoy the performance, his enjoyment comes under the head of dissolved apprehension, or disillusion after taking things too seriously. By far the larger share of the pleasure of the practical joke certainly falls, however, to the perpetrator, who in this case, too, realises a “sudden glory,” an increased sense of power.

(_d_) Once more, laughter is a common accompaniment of all varieties of contest or sharp encounter, both physical and mental. When, as in the case of the savage, the schoolboy and the civilised soldier, it breaks out after bodily fight, it {79} has some of the characteristics of nervous laughter. It is a concomitant of a sudden remission of physical and mental strain, of a dissolution of the attitude of apprehensive self-protection. In most cases, since it is “they laugh that win,” the feeling of relief is reinforced by that of contemptuous exultation at the first taste of victory.

A prolonged combat, if not too unequal, offers on both sides frequent openings for these reliefs of tension and upspringings of the exultant mood. A good fighter in the ring is, I understand, supposed to be able now and again to relieve the grimness of the situation by a sweet smile. This is certainly true of all mental contests. Nothing is more remarkable in the study of popular laughter than the way in which it seems to penetrate those relations and dealings of social life which involve sharp contest and crossing of wits. These will be illustrated more fully by-and-by. It is enough here, to allude to the enormous influence of contests between the sexes on the development of wit and a lively sense of the ludicrous.

(_e_) As a last group of situations favourable to the experience of joyous expansion we have those in which an unusual degree of solemnity is forced upon us. This has already been touched on. Extremes seem to meet here. It might be expected that an impulse born of the play-mood would find its natural dwelling-place in scenes of social gaiety and conviviality. And in the days when society was gay the festive board was doubtless the focus of the activity of the mirthful spirit. In our time it seems almost more natural to associate a laugh with a funeral ceremony than with a dinner-party. Yet the art of extracting fun from solemn things is not of to-day, as may be seen by a glance at the jokes of the church architect and the play writer of the Middle Ages. In such bizarre intrusions of the droll {80} into the domain of the solemn we seem to find the struggling of an irrepressible gladness of spirit against the bonds which threaten to strangle it.

Whether the invasion of the territory of the solemn by the jocose results in a barely mastered impulse to laugh, depends on variable conditions. The frivolous mind, hardly touched by the gravity of the occasion, will, no doubt, often be the first to welcome the delivering hand. Yet it is an error to suppose that a tendency to laugh on a solemn occasion shows want of genuine emotion. The sincerest worshipper in a church may, if he have the requisite sensibility, be moved to laughter by some grotesque incident, such as the _mal à propos_ remark of a garrulous child. For the point of our theory is that laughter in such cases is an escape from pressure; and the man who feels deeply at such a moment may experience an emotional pressure which equals, if it does not exceed, that of the external constraint which the non-reverent “worshipper” is experiencing. It is true, of course, that the deeper the feeling the greater the inertia that will have to be overcome before the laughing impulse can make way for itself. Yet here, again, we must remember that emotional temperaments vary, and that with some a genuine awe and even an intense grief may yield now and again for a moment to the challenge of the laughable when its note catches the ear.

The last remarks suggest that in any attempt to deal with the conditions favourable to laughter reference should be made to those physiological characteristics which are supposed to determine the particular temperament of a man: his special bent, say, towards jollity on the one hand, or towards a brooding melancholy on the other. Our forefathers had pretty definite ideas about the sort of bodily constitution which was the foundation of the {81} laughter-loving temper. A full “habit” tending to obesity, as in Falstaff, was, and is, I believe, popularly supposed to be a mainstay of the laughing spirit. The saying “Laugh and grow fat” may imply a vague apprehension of this relation, as well as a recognition of the benefits of laughter. Yet the precise organic substrate of this happy endowment is unknown. Health and all that makes for “good spirits” are no doubt favourable to a voluble laughter of the elemental kind. On the other hand, as we shall see, the laughing capacity frequently co-exists with physiological conditions of quite another kind. Men are to be found of a lean habit, and with a strong bent to grave reflection, who are nevertheless able, not merely to provoke laughter from others, like the “melancholy Jaques,” but themselves to contribute a sonorous laughter to the higher intellectual domains of mirth. It is conceivable that the disposition to laugh may have its own restricted physiological conditions in a special instability of the mechanism concerned. This again may presumably include some as yet undefinable property of the nerve-centres which favours rapid change in the mode of brain activity, and those sudden collapses of tension which seem to be the immediate physiological antecedent of the motor discharge in laughter. {82}