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XV.

THE WILL

SINCE mentality terminates naturally in outward conduct, the final chapter in psychology has to be the chapter on the will. But the word 'will' can be used in a broader and in a narrower sense. In the broader sense, it designates our entire capacity for impulsive and active life, including our instinctive reactions and those forms of behavior that have become secondarily automatic and semi-unconscious through frequent repetition. In the narrower sense, acts of will are such acts only as cannot be inattentively performed. A distinct idea of what they are, and a deliberate fiat on the mind's part, must precede their execution.

Such acts are often characterized by hesitation, and accompanied by a feeling, altogether peculiar, of resolve, a feeling which may or may not carry with it a further feeling of effort. In my earlier talks, I said so much of our impulsive tendencies that I will restrict myself in what follows to volition in this narrower sense of the term.

All our deeds were considered by the early psychologists to be due to a peculiar faculty called Davetion the will, without whose fiat action could not occur. Thoughts and impressions, being intrinsically inactive, were supposed to produce conduct only through the intermediation of this superior agent. Until they twitched its coat-tails, so to speak, no outward behavior could occur. This doctrine was long ago exploded by the discovery of the phenomena of reflex action, in which sensible impressions, as you know, produce movement immediately and of themselves. The doctrine may also be considered exploded as far as ideas go.

The fact is that there is no sort of consciousness whatever, be it sensation, feeling, or idea, which does not directly and of itself tend to discharge into some motor effect. The motor effect need not always be an outward stroke of behavior. It may be only an alteration of the heart-beats or breathing, or a modification in the distribution of blood, such as blushing or turning pale; or else a secretion of tears, or what not. But, in any case, it is there in some shape when any consciousness is there; and a belief as fundamental as any in modern psychology is the belief at last attained

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that conscious processes of any sort, conscious processes merely as such must pass over into motion, open or concealed.

The least complicated case of this tendency is the case of a mind possessed by only a single idea. If that idea be of an object connected with a native impulse, the impulse will immediately proceed to discharge. If it be the idea of a movement, the movement will occur. Such a case of action from a single idea has been distinguished from more complex cases by the name of ideomotor' action, meaning action without express decision or effort. Most of the habitual actions to which we are trained are of this ideo-motor sort. We perceive, for instance, that the door is open, and we rise and shut it; we perceive some raisins in a dish before us, and extend our hand and carry one of them to our mouth without interrupting the conversation; or, when lying in bed, we suddenly think that we shall be late for breakfast, and instantly we get up with no particular exertion or resolve. All the ingrained procedures by which life is carried on the manners and customs, dressing and undressing, acts of salutation, etc. are executed in this semi-automatic way unhesitatingly and efficiently, the very

outermost margin of consciousness seeming to be concerned in them, while the focus may be occupied with widely different things.

But now turn to a more complicated case. Suppose two thoughts to be in the mind together, of which one, A, taken alone, would discharge itself in a certain action, but of which the other, B, suggests an action of a different sort, or a consequence of the first action calculated to make us shrink. The psychologists now say that the second idea, B, will probably arrest or inhibit the motor effects of the first idea, A. One word, then, about inhibition' in general, to make this particular case more clear.

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One of the most interesting discoveries of physiology was the discovery, made simultaneously in France and Germany fifty years ago, that nerve currents do not only start muscles into action, but may check action already going on or keep it from occurring as it otherwise might. Nerves of arrest were thus distinguished alongside of motor nerves. The pneumogastric nerve, for example, if stimulated, arrests the movements of the heart: the splanchnic nerve arrests those of the intestines, if already begun. But it soon appeared that this

THE FUNCTION OF INHIBITION

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was too narrow a way of looking at the matter, and that arrest is not so much the specific function of certain nerves as a general function which any part of the nervous system may exert upon other parts under the appropriate conditions. The higher centres, for example, seem to exert a constant inhibitive influence on the excitability of those below. The reflexes of an animal with its hemispheres wholly or in part removed become exaggerated. You all know that common reflex in dogs, whereby, if you scratch the animal's side, the corresponding hind leg will begin to make scratching movements, usually in the air. Now in dogs with mutilated hemispheres this scratching reflex is so incessant that, as Goltz first described them, the hair gets all worn off their sides. In idiots, the functions of the hemispheres being largely in abeyance, the lower impulses, not inhibited, as they would be in normal human beings, often express themselves in most odious ways. You know also how any higher emotional tendency will quench a lower one. Fear arrests appetite, maternal love annuls fear, respect checks sensuality, and the like; and in the more subtile manifestations of the moral life, whenever an ideal stirring is suddenly quickened into inten

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