AT TIMES ONE SENSE IS BEST NOT UTILIZED.--At times teaching may well omit one sense in its appeal, because that sense will tend to confuse the learning, and will, when the method is learned, be otherwise utilized than it could be during the learning process. In teaching the "touch system" of typewriting,[18] the position of the keys is quickly remembered by having the key named aloud and at the same time struck with the assigned finger, the eyes being blindfolded. Thus hearing is utilized, also mouth muscles and finger muscles, but _not_ sight. IMPORTANCE OF FATIGUE RECOGNIZED.--A large part of the success of sense appeal and sense training of Scientific Management is in the appreciation of the importance of fatigue. This was early recognized by Dr. Taylor, and is constantly receiving study from all those interested in Scientific Management. PSYCHOLOGY ALREADY AIDING THE INDUSTRIES IN SUCH STUDY.--Study of the _Psychological Review_ will demonstrate the deep and increasing interest of psychologists in the subject of fatigue. The importance of such stimulating and helpful work as that done by Doctor A. Imbert of the University of Montpellier, France, is great.[19] Not only are the results of his investigations commercially valuable, but also they are valuable as indicating the close connection between Psychology and Industrial Efficiency. IMPORTANCE OF HABITS.[20]--Prof. William James says "an acquired habit, from the psychological point of view, is nothing but a new pathway of discharge formed in the brain, by which certain incoming currents ever after tend to escape." And again,--"First, habit simplifies our movements, makes them accurate, and diminishes fatigue,"[21] and habit diminishes the conscious attention with which our acts are performed. Again he says, page 144, "The great thing, then, in all education, is to make our nervous system our ally instead of an enemy; as it is to fund and capitalize our acquisitions, and live at ease upon the interest of the fund. For this we must make automatic and habitual, as early as possible, as many useful actions as we can, and guard against the growing into ways that are likely to be disadvantageous to us, as we should guard against the plague." These quotations demonstrate the importance of habit. How deep these paths of discharge are, is illustrated by the fact that often a German, having spent the early years of his school life in Germany, will, even after learning to speak, read, write and think in English, find it difficult to figure in anything but German.