This further work will have to be a work of cooeperation.  The nature of this problem demands a relatively large number of persons for the experimental treatment.  With most experimental researches in our psychological laboratories, the number of the subjects experimented on is not so important as the number of experiments made with a few well-trained participants.  But with the questions of applied psychology the number of persons plays a much more significant role, as the individual differences become of greatest importance.  The same problems ought therefore to be studied in various places, so that the results may be exchanged and compared.  Moreover, these psychological economic investigations naturally lead beyond the possibilities of the university laboratories.  To a certain degree this was true of other parts of applied psychology as well.  Educational and medical experimental psychology could not reach their fullest productivity until the experiment was systematically carried into the schoolroom and the psychiatric clinic.  But the classroom and the hospital are relatively accessible places for the scientific worker, as both are anyhow conducted under a scientific point of view.  The teacher and the physician can easily learn to perform valuable experiments with school children or with patients.  This favorable condition is lacking in the workshop and the factory, in the banks and the markets.  The academic psychologist will be able to undertake work there only with a very disturbing expenditure of time and only under exceptional conditions.  If such experiments, for instance, with laborers in a factory or employees of a railway are to advance beyond the faint first efforts of to-day and are really to become serviceable to the cultural progress of our time with effective completeness, they ought not to remain an accidental appendix to the theoretical laboratories.  Either the universities must create special laboratories for applied psychology or independent research institutes must be founded which attack the new concrete problems under the point of view of national political economy.  Experimental workshops could be created which are really adjusted to the special practical needs and to which a sufficiently large number of persons could be drawn for the systematic researches.  The ideal solution for the United States would be a governmental bureau for applied psychology, with special reference to the psychology of commerce and industry, similar to the model agricultural stations all over the land under the Department of Agriculture.

Only when such a broad foundation has been secured will the time be ripe to carry the method systematically into the daily work.  The aim will never be for real experimental researches to be performed by the foreman in the workshop or by the superintendent in the factory.  But slowly a certain acknowledged system of rules and prescriptions may be worked out which may be used as patterns, and which will not