EXPRESSION. 380 EXPRESSION. ante of the emotion (q.v.) that bodily expres- sion becomes so well marked as to be accessible to external observation. One of the peculiar features of emotional ex- pression is the seemingly useless and even posi- tively disadvantageous nature of certain oi the bodily disturbances. Why should we curl our lip in scorn': Why should we clap our hands for joy, or blush for shame, or tremble for fear? It is in answer to such questions that various authori- ties have deduced what are called 'the principles of expression.' with the aim at once of classifying and of explaining the genesis of the expressive movements. The best-known and most important contributions to this subject are those of Darwin, Wundt, and James. In 1873 Darwin brought forward three prin- ciples, by which he hoped to account for most, if not all, of the expressive gestures involuntarily used by man and the lower animals under the in- fluence* of the emotions. Darwin's principles are as follows: (1) The principle of serviceable as- sociated habits. Many complicated movements which under certain circumstances were of direct or indirect use are retained when their use is no longer apparent, in consequence of the general laws of association, habit, and inheritance. Thus the cat executes peculiar 'pawing' movements with the fore feet when it is pleased. These move- ments are the relic of the purposeful use of the same movements to start or increase the flow of milk from the mammary glands of the mother. The movements became thereby associated with a pleasurable and satisfied consciousness, and tend to recur whenever such a consciousness re- curs. Wundt considers that this principle is but a special ease of Darwin's third, the direct action of the nervous system ; for the overflow of ner- vous energy takes those paths which arc habitual and most frequently used. (2) The principle of antithesis. As Darwin explains it. "every move- ment which we have voluntarily performed throughout our lives has required the action of certain muscles ; and when we have performed a direct 1 opposite movement, an opposite set of muscles has been habitually brought into play. . . . So when actions of one kind have become firmly associated with any sensation or emotion, it appears natural thai actions of a directly opposite kind, though of no use, should be un- consciously performed through habit and associa- tion under the influence of a directly opposite sensation or emotion." Thus impotence is ex- pressed by raised eyebrows, shrugged shoulders, and open palms; since these are the antithesis of th. frowning brow, the thrown hack shoulders, and the clenched lists, symbolic of rage and power. James says in comment: "No doubt a certain number of movements can be formulated under this law: but whether it expresses a causal principle i- more doubtful. It has been by I critics considered the leasf successful of Darwin's speculations on this subject." (3) The principle of il" ilif:, i action nf the nervous sys- • ol c lion- due t<> tiie constitution of the nervous rystem, independent from the first of the will, and independent i lertain exteni of habit. Tie e of lai ge quanl ii ies of nen ous enei - ; demo rid unu ual outlet from the i entral nei -. " ' tern. This overflow takes plai e ai cording to the preformed connections of the nervous elements. It- results an' visible iii the gen< I. function due to the exciting or inhibitory effects of these irradiations of energy from the central nervous system, tin this principle are explained such phenomena as the muscular tremors of fear or of great joy; the increased glandular activity of the liver, kidneys, and mamma:; the alterations in cardiac and vaso- motor functions: and such movements as the clapping of the hands for joy. It is admitted by James, and is practically identical with the first principle of Wundt. Wundt's principles are likewise three in num- ber. ( 1 ) The principle of direct change of inner- vation. This is but a different, wording of what we have just discussed as the third principle of Darwin. It involves the principle of the heredi- tary transmission of certain nervous connections; thus the reflex of weeping, which probably falls in origin under the third principle, has by inher- itance come to take its place under the first. The transmission of a characteristic family physiog- nomy or general expressive attitude is very com- mon; and we invariably argue from the physical similarity to a similarity of mood, even though there be no possibility of imitation of the parents by the children. These direct changes in innerva- tion are almost always accompanied by a notice- able reactionary effect upon the ideational course of the emotion. The frightened man stutters, not merely because his tongue mechanically refuses service, but also because his thoughts are really brought to a standstill. (2) The principle of the association of analogous smsations is based upon the fact that sensations of similar feeling-tone easily associate and reinforce one another. This process forms the basis of the most characteristic of all emotive expressions, the 'mimetic move- ments.' These are physiologically conditioned by reflex movements in and about the facial sense organs : thus the expression which stands for ■bitter' is an arrangement of the parts of the buccal cavity most sensitive to bitter in such a way as to prevent their excessive stimulation by the unpleasant taste. The 'sweet' expression, on the contrary, is that calculated to favor the con- tinued stimulation of the tip of the tongue, the part most sensitive to sweet substances. By vir- tue of the second principle these reactions have come to appear in response not only to an ac- tually bitter taste, but also to an emotional con- dition which possesses the same general feeling- tone. So the expression has become symbolic. A wry face may denote a mental as well as a physical pain. (3) The principle of the connec- tion of movement with sense ideas explains all the facial expressions and gestures which are not included under the two previous principles. Here belong movements of the arms and hands, the clenching of the fists in anger, and also certain facial expressions, such as the curling of the lip in 3Com, and the staring eyes of surprise. The principle seems closely allied to Darwin's first. It is not to be thought that any complex expres- sion of emotion must be explained by a single principle. Such phenomena :i- laughing and weeping demand the use of all three principles for t heir elucidation. James proposes the five following principles: (1) The weakened repetition of movements which formi rly were of utility to the subject. This is equivalent to Darwin's first, proposition, (2) The principle of reacting similarly In analo- gous-feeling stimuli. This is identical with Wundt's second principle. (3) The principle of
