Page:Popular Science Monthly Volume 50.djvu/73

Rh of perception, of how it increases the number of judgments and the accuracy of them. It enriches also in content our ideas of form, of time, of distance, of place, of resistance, etc.

Association, moreover, is very closely related to this side, and the employment of the motor activities in mental acquirement aids memory. Prof. Baldwin says very emphatically that association has a motor foundation from the first, and that the elements hold together in memory because they are used together in action, and as action becomes one, but yet complex, so the mental content tends to become one, yet complex. He says further: "We have to-day got beyond the view that memory is a faculty which takes up content and remembers it. It is, on the contrary, now known to be a function of the content remembered." In my view this function of the content depends upon the variety of association and also upon volition, and both of these are best built up by that which gives the fullest possible functioning of the nervous mechanism during its developing period—namely, the fullest and most varied use of the motor activities warrantable. This, bear in mind, means a much more prominent use of these activities than has yet been made in our schools.

In the act of teaching or learning, old elements are constantly revived through extrinsic stimulation and volition. But it is, after all, the motor which sets those processes going that revive the older mental elements, and it is through the motor that the older elements have placed beside them images and judgments containing a greater number of elements than they would otherwise have had. Thus arises a more varied association. The new impressions become blended with the old, but at the same time the new have more elements in them because of the development of the motor side. Accordingly, the new content is a fuller one—that is, it has more clews by which its revival may be produced. For Donaldson, in those two remarkable chapters which close his recent work, The Growth of the Brain, not only expressly says that "education consists in modifications of the central nervous system," but also that "the value of mental images appears also as dependent on the number and balance of the secondary sensations which accompany them. The greater the number of these, the more certain and precise is our thought," and "as the possibility of forming the extra images is curtailed, the conception becomes weaker, more special, and less reliable."

The reasons why we attribute such value to paper folding, drawing, coloring, clay modeling, of late so largely introduced into courses of study and with such profit both to pupil and to teacher, must now be very evident. On the same grounds manual training is appreciated to-day, and is winning wider adoption because of its employment of the motor activities. It may be said,