An Essay on Laughter: Its Forms, Its Causes, Its Development and Its Value

by James Sully

Dr. Robinson goes a step farther and seeks to show that the areas of the bodily surface which are specially ticklish in children are those likely to be attacked in serious warfare. In nearly all of them, he says, some important structure, such as a large artery, is close to the surface and would be liable to injury if the skin were penetrated. They would thus be highly vulnerable regions, and consequently those which would be singled out for attacks by teeth or claws. He argues that the same relation holds in the case of animals which attack one another in the same way as man. The regions of special ticklishness in their case, too, appear to correspond, roughly at least, with vulnerable regions. Indeed, in the young chimpanzee and the young ourang these ticklish areas are approximately the same as in the child. {181}

From all this he concludes that ticklishness, being bound up with the mimic warfare which fills so large a space in the life of many young animals, has its utility. The strong liking to be tickled, which children and, apparently, some other young animals express, serves, in combination with the playful impulse to carry out this gentle mode of attack, to develop mimic attacks and defences which are of high value as training for the later and serious warfare.

These applications of the evolution theory are certainly interesting and promising. I think the idea of relief from parasites might be worked out further. May it not be that the light touches given by the fingers of the parent, or other member of the ancestral family when hunting for parasites on the surface of the young animal, have, by association with the effects of relief from the troublesome visitors, developed an agreeable feeling-tone? As we have seen, the laughter of tickling has a distinctly mental antecedent; it appears in the child, only when he is beginning to enjoy laughingly little pinches on the cheek, and otherwise to show a germ of a sense of fun. The light touches, reminiscent at once of unpleasant settlers, and of delivering fingers, would, one imagines, be exactly fitted to supply that dissolution into nothing of momentary apprehension indicated by our analysis of the mental factor in tickling.

With respect to Dr. Robinson’s hypothesis, it may be acknowledged ungrudgingly to be a brilliant piece of hypothetical construction. But, as the writer frankly confesses, the facts, here and there, do not point in its direction. A very serious objection is the fact that the sole of the foot and the palm of the hand are not taken into account in his attempt to establish a correspondence between the ticklish areas of {182} the surface and a high degree of vulnerability. In Stanley Hall’s returns it is the sole of the foot which is most frequently mentioned as a ticklish area; and, as we have seen, it was the first to give rise to laughter in the case of one child at least.[116]

There is another and more serious objection to Dr. Robinson’s theory as an explanation of laughter. One may urge that the occurrence of such violent movements would, by shaking the body and by inducing fatigue much earlier than need be, pretty certainly be detrimental to that prolonged practice of skill in attack and defence, to which Dr. Robinson attaches so much importance.

The supposition that tickling is a variety of play developed by natural selection among combative animals is, I think, highly probable. The play of animals, like that of children, is largely a form of social activity involving a playmate; and is apt, as we know, to take the form of attack and defence, as in chasing, throwing over, pretending to bite, etc. These playful attacks are, as we have seen, closely related to teasing; indeed, teasing may be viewed as merely a play-imitation of the first stage of combat, that of challenging or exciting to contest.[117] Tickling pretty obviously finds a fitting place among the simpler forms of playful combat which have a teasing-like character. Moreover, these forms of social play all seem to show, in a particularly clear manner, the utility referred to in the preceding chapter. {183}

Now, this idea will, I think, help us to understand how loud and prolonged laughter came to join itself to the combative game of tickling and being tickled. If play—pure, good-natured play—was to be developed out of teasing attacks, it would become a matter of the highest importance that it should be clearly understood to be such. This would mean, first of all, that the assailant made it clear that his aim was not serious attack, but its playful semblance; and secondly, that the attacked party expressed his readiness to accept the assault in good part as sport. It would be of the greatest consequence to the animal that chanced to be in the play-mood and wished to make overtures of friendly combat that he should be sure of an equally gamesome attitude in the recipient of the challenge. One may see this by watching what happens when a dog, unwisely trying to force a frolic on another dog, is met by a growl and possibly by an uncovering of the canine teeth. Now, what better sign of good-temper, of readiness to accept the attack as pure fun, could nature have invented than the laugh? The smile is, no doubt, a pretty good indicator in some circumstances. Yet one must remember that the rudimentary smile of an ape-like ancestor may, now and again, have been misleading, as our own smiles are apt to be. A laugh would presumably be less easy to affect in such circumstances than a smile; and, in any case, it would be far less liable to be overlooked.

In saying that the laughter which accompanies tickling and other closely allied forms of play in children owes its value to its being an admirable way of announcing the friendly playful mood, I do not mean that other signs are absent. Dr. L. Robinson reminds us that a tickled child will roll over on his back just like a puppy. The laughter and the rolling over seem to be two congenitally connected {184} modes of abandonment to the playful attack. In the young of other ticklish animals, e.g., the puppy, the rolling over may of itself suffice to give the friendly signal.

It seems not unlikely that this consideration, the utility of laughter as a guarantee to a playful challenger that his overtures will be received in the proper spirit, applies to the evolution of all laughter which enters into such forms of social play as the pretence to attack, to frighten, and generally what we call good-natured teasing. It has been suggested that teasing might well be taken as the starting-point in the evolution of play.[118] By adopting this idea, and by regarding laughter, in its elementary form, as essentially a feature of social play, we might set out with this consideration of utility in constructing our theory of the evolution of laughter. One is tempted, too, to follow this course by the fact, recognised in common language, that much, at least, of the later and more refined laughter is analogous to the effect of tickling.[119]

Nevertheless, as we have seen, the best evidence attainable points to the conclusion that this simple form of the laughter of social play was preceded by, and grew out of, a less specialised kind of laughter, that of sudden accession of pleasure. We may conjecture that the laughter provoked by tickling was reached in the evolution of our race soon after this reaction passed out of its primal and undifferentiated form as a general sign of pleasurable excitement, and began to be specialised as the expression of mental gaiety and of something like our hilarity. The fact, noted above, {185} that children only laugh in response to tickling when they are in a pleasurable state of mind seems to confirm the hypothesis that the love of fun, which is at the bottom of tickling and makes it perhaps the earliest clear instance of mirthful play with its element of make-believe, first emerged gradually out of a more general feeling of gladness.