if the reactions, or associations, or memories, or tendencies of
attention, or emotions of a subject were measured really with that
scientific thoroughness which is the ideal of research, long months of
experiments would be needed, and little could be hoped for from tests
to be performed in half an hour. But this somewhat haughty reserve
which was quite justified twenty years ago has become obsolete and
would be meaningless to-day. On the one side the methods themselves
have been multiplied; for each mental act like memory, attention, and
so on, dozens of well-studied tests are at our disposal, which are
adjusted to the finest ramifications of the functions.[15] On the
other side the interest in individual differences and in applied
psychology has steadily grown, and through it an understanding for the
real meaning of the tests has been gained. Their value, indeed, lies
exclusively in their relation to the practical problems. Where
theoretical questions are to be answered and scientific studies
concerning the laws and variations of the mind are to be undertaken,
the long series of laboratory experiments carried on with patience and
devotion are indispensable and can never be replaced by the short-cut
methods of the tests. But where practical tasks of pedagogy or
jurisprudence or medicine, or especially of commerce and industry, are
before us, the method of tests ought to be sovereign. It can be
adapted to the special situations and can succeed perfectly, if the
task is to discover the outlines of the mental individuality for
particular practical work.

The only real difficulty of the method lies in the ease with which it
can be used. A device which presupposes complicated instruments deters
the layman and will be used only by those who are well trained.
Moreover, the amateur would not think of constructing and adapting
such apparatus himself. But when nothing is necessary but to use words
or numbers or syllables or pictures, or, as in those experiments which
we just described, newspapers and so on, any one feels justified in
applying the scheme or in replacing it by a new apparently better one
according to his caprice. The manifoldness of the proposed tests for
special functions, is therefore enormous to-day. What is needed now is
surely much more that order be brought into this chaos of
propositions, and that definite norms and standards be secured for
certain chief examinations, than that the number of variations simp