Page:Popular Science Monthly Volume 13.djvu/470

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454
THE POPULAR SCIENCE MONTHLY.

not be determined or controlled by that symbol—that state of consciousness—that mental part of the phenomena which we call volition. Therefore, if from a voluntary movement we strike out the only mental part—the volition—which, as we have seen, is not a factor, what is left is as purely organic, and hence as purely reflex or automatic, as the movements of a decapitated frog upon the application of an external irritant. Of the truth of this we may satisfy ourselves by simply looking at the nature of a voluntary movement from another point of view. Thus, I will to move my arm, and it moves. The only voluntary part of that very complex operation is the volition itself. I do not intentionally and knowingly direct the nervous discharge along one set of nerves rather than another, or upon one set of muscles rather than another; nor do I knowingly and intentionally cause one set to contract and another to relax, or one to contract much, and another little, and another less. All these things, which are so numerous and complicated in that one movement, and which constitute the whole of the mechanism, are purely automatic, being not in the least dependent upon the mental part—the volition—although wholly dependent upon that organic activity of which the volition is a symbol in consciousness. It is easy to understand, therefore, that if the molecular action which generates the nervous force that causes a reflex movement could be symbolized in consciousness, that symbol could not be called anything but a volition—a mandate for the movement. As many reflex movements are movements which were once voluntary, and have become reflex by a withdrawal of them from the sphere of consciousness, to relate them again to consciousness would be to make them again voluntary. While it is very easy to understand how a reflex movement might thus be converted into, or restored back to, a voluntary movement, it is an actual fact that by dislocating consciousness from its connections with voluntary movements we at once make them reflex or automatic, as is the case, for example, in many habitual or oft-repeated movements, such as the fingering of the keys of a piano when the music is known by heart. The following singular case is also in point: Many years ago, a medical gentleman related to me a case which came under his own observation, namely, that of a lawyer, who, without any other perceptible physical or mental disorder, would, in the course of ordinary conversation, let slip one or another legal term between words and in sentences with which it had no connection whatever. They seemed to utter themselves without any volition on his part, and in fact he did not know that one was coming until it was pronounced. The muscular movements in such cases are wholly automatic, which means wholly organic, without any associated mental phenomena.

From the foregoing considerations it is evident that a scientific solution of the problem of voluntary motion (and that of the will which is based upon it) requires a full and separate consideration and explanation of four distinct branches of the subject, namely: