experimental schemes, even of the simplest form, are in question, it
seems a matter of course that the plan ought to be prescribed by real
scientists who specialize in the psychological field. The
psychologist, for instance, surely cannot agree to a method which
measures the memory by such a method of having spoken sentences
repeated and the quality of the memory faculty naïvely graded
according to the results. He knows too well that there are many
different kinds of memory, and would always determine first which type
of memory functions is to be examined if memory achievements are
needed for a particular calling.

But even with a more exact method of experimenting, such a procedure
would not be sufficient to solve the true problem. A second step would
still be necessary: namely, the adaptation of the experimental result
to the special psychological requirements of the economic activity;
and this again presupposes an independent psychological analysis. Most
of the previous efforts have suffered from the carelessness with which
this second step was ignored, and the special mental requirements were
treated as a matter of course upon which any layman could judge. In
reality they need the most careful psychological analysis, and only if
this is carried out with the means of scientific psychology, can a
study of the abilities of the individual become serviceable to the
demands of the market. Such a psychological disentangling of the
requirements of the callings, in the interest of guidance, is
attempted in the material which the various vocational institutes have
prepared, but it seldom goes beyond commonplaces. We read there, for
instance,[5] for the confectioner: "Boys in this industry must be
clean, quick, and strong. The most important qualities desired are
neatness and adaptability to routine"; or, for the future baker, the
boy "ought to know how to conduct himself and to meet the public"; or