the differences between the individuals by the methods of experimental
science was after all the most important advance toward the practical
application of psychology. The study of the individual differences
itself is not applied psychology, but it is the presupposition without
which applied psychology would have remained a phantom.




II

THE DEMANDS OF PRACTICAL LIFE


While in this way the progress of psychology itself and the
development of the psychology of individual differences favored the
growth of applied psychology, there arose at the same time an
increasing demand in the midst of practical life. Especially the
teachers and the physicians, later the lawyers as well, looked for
help from exact psychology. The science of education and instruction
had always had some contact with the science of the mind, as the
pedagogues could never forget that the mental development of the child
has to stand in the centre of educational thought. For a long while
pedagogy was still leaning on a philosophical psychology, after that
old-fashioned study of the soul had been given up in psychological
quarters. At last, in the days of progressive experimental psychology,
the time came when the teachers under the pressure of their new needs
began to inquire how far the modern laboratory could aid them in the
classroom. The pedagogical psychology of memory, of attention, of
will, and of intellect was systematically worked up by men with