industries, and metal industries, blanks containing 26 questions, and received more than 5000 replies.  The questions referred to the pleasure and interest in the work, to preferences, to fatigue, to the thoughts during the work, to the means of recreation, to the attitude toward the wages, to the emotional situation, and so on.  The 5000 answers allowed manifold classifications.  The various mental types of men could be examined, the influence of the machine, the attitude toward monotony, the changes of pleasure and interest in the work with the age of the laborer, the time at which fatigue becomes noticeable, and so on.  Many psychological elements of industrial life thus come to a sharp focus and the strong individual differences could not be brought out in a more characteristic way.  Yet, all taken together, even such a careful investigation on a psychostatistical basis strongly suggests that a few careful experimental investigations could lead further than such a heaping-up of material gathered from men who are untrained in self-observation and in accurate reports, and above all who are accessible to any kind of suggestion and preconceived idea.  The experimental method is certainly not the only one which can contribute to reforms in industrial life and the reinforcement of industrial efficiency, but all signs indicate that the future will find it the most productive and most reliable.

PART III

THE BEST POSSIBLE EFFECT

XIX

THE SATISFACTION OF ECONOMIC DEMANDS

Every economic function comes in contact with the mental life of man, first from the fact that the work is produced by the psyche of personalities.  This gave us the material for the first two parts of our discussion.  We asked what mind is best fitted for the particular kind of work, and how the mind can be led to the best output of work.  But it is evident that the real meaning of the economic process expresses itself in an entirely different contact between work and mind.  The economic activity is separated from all other processes in the world, not by the fact that it involves labor and achievement by personalities, but by the fact that this labor satisfies a certain group of human desires which we acknowledge as economic.  The mere performance of labor, with all the psychical traits of attention and fatigue and will-impulses and personal qualities, does not in itself constitute anything of economic value.  For instance, the sportsman who climbs a glacier also performs such a fatiguing activity which demands the greatest effort of attention and will; and yet the psychotechnics of sport do not belong in economic psychology, because this mountain climbing does not satisfy economic desires.  The ultimate characteristic which designates an activity as economic is accordingly a certain effect on human souls.  The whole whirl of the economic world