"Expressive Movements," Another Sort of Preparatory Reactions
Though we know little of any internal response in many of the emotions, we almost always find some characteristic external movement, such as smiling, scowling, pouting, sneering, sobbing, screaming, shouting or dancing. By aid of such "expressive movements" we are sometimes able to judge the emotional state of another person. But what is the sense of these movements? At first thought, the question itself is senseless, the movements are so much a matter of course, while on second thought they certainly do seem odd. What sense is there is protruding the lips when sulky, [{127}] or in drawing up the corners of the mouth and showing the canine teeth in contempt? Perhaps they are just odd tricks of instinct--for we agreed in the preceding chapter not to assume all instinctive responses to be useful. Darwin, however, after studying a great many of these expressive movements, both in men and in animals, reached the conclusion that, if not of present utility, they were survivals of acts that had been useful earlier in the life of the individual or of the race.
Shaking the head from side to side, in negation or unwillingness, dates back to the nursing period of the individual's life, when this movement was made in rejecting undesired food. Directly useful in this case, it was carried over to analogous situations that aroused the child's reluctance.
Showing the teeth in scorn dates back, according to Darwin, to a prehuman stage of development, and is seen in its useful form in animals like the dog or gorilla that have large canine teeth. Baring the teeth in these animals is a preparation for using the teeth; and often, also, it frightens the enemy away and saves the bother of actually attacking "small fry". The movement, Darwin urges, has survived in the race, even after fighting with the teeth has largely disappeared.
Many other expressive movements are traced back in a similar way, though it must be admitted that the racial survivals are usually less convincing than those from the infancy of the individual. The nasal expression in disgust was originally a defensive movement against bad odors; and the set lips of determination went primarily with the set glottis and rigid chest that are useful in lifting heavy weights or in other severe muscular efforts. Such movements, directly useful in certain simple situations, become linked up with analogous situations in the course of the [{128}] individual's experience. Many of them, certainly, we can regard as preparatory reactions.