spring on its prey, it assumed a crouching attitude, curled its tail
from side to side and depressed its ears? Even still less can I believe
that my dog voluntarily put on his dejected attitude and _hot-house
face_, which formed so complete a contrast to his previous cheerful
attitude and whole bearing. It cannot be supposed that he knew that I
should understand his expression, and that he could thus soften my
heart and make me give up visiting the hot-house.
Hence for the development of the movements which come under the present
head, some other principle, distinct from the will and consciousness,
must have intervened. This principle appears to be that every movement
which we have voluntarily performed throughout our lives has required
the action of certain muscles; and when we have performed a directly
opposite movement, an opposite set of muscles has been habitually
brought into play, as in turning to the right or to the left, in
pushing away or pulling an object towards us, and in lifting or
lowering a weight. So strongly are our intentions and movements
associated together, that if we eagerly wish an object to move in any
direction, we can hardly avoid moving our bodies in the same direction,
although we may be perfectly aware that this can have no influence. A
good illustration of this fact has already been given in the
Introduction, namely, in the grotesque movements of a young and eager
billiard-player, whilst watching the course of his ball. A man or child
in a passion, if he tells any one in a loud voice to begone, generally
moves his arm as if to push him away, although the offender may not be
standing near, and although there may be not the least need to explain
by a gesture what is meant. On the other hand, if we eagerly desire
some one to approach us closely, we act as if pulling him towards us;
and so in innumerable other instances.
As the performance of ordinary movements of an opposite kind, under
opposite impulses of the will, has become habitual in us and in the
lower animals, so when actions of one kind have become firmly
associated with any sensation or emotion, it appears natural that
actions of a directly opposite kind, though of no use, should be
unconsciously performed through habit and association, under the
influence of a directly opposite sensation or emotion. On this
principle alone can I understand how the gestures and expressions which
come under the present head of antithesis have originated. If indeed
they are serviceable to man or to any other animal, in aid of
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