that these can be secured partly by sense impressions, and
once more especially by words.

It is a matter of course to the physician that application of any sense
influence on the brain demands a most subtle analysis of the
psychophysical situation. Therefore he gives no less attention to the
disentangling of the whole history of the individual brain, to its
stored-up energies and to its mental possibilities. If he knows the
psychophysical status, and finally if he knows the means of influencing
those psychophysical organs which stimulate or inhibit the disturbed
central parts, he can foresee the psychophysical effects with a certain
definiteness. Thus everything depends upon the sharpest possible, almost
microscopic, mental analysis, together with a most thorough examination
of the whole nervous system and the most careful calculation of the
mental influences applied. The vagueness of the religious appeal
transforms itself into an exact calculation and the unity of the soul
which seeks spiritual uplift transforms itself into a mental mechanism
of bewildering complexity, and yet not more complex than the physical
organism, to which for instance, the chemical means of the physician
administer. To-day medical science is certainly only in the beginning of
this great movement. Especially the analysis of the psychophysical
conditions still lacks a sufficient refinement of method. But at least
the causal principle is now fully recognized and the scientific man of
today no longer doubts that this whole play of psychotherapeutic
processes goes on as a causal process in the psychophysical system of
the individual without any mysteriousness, without any magnetic
influences, without any miraculous interference, without any agencies
except those which are working in our ordinary mental life in attention
and reaction, in memory and sleep.

It is surprising how late this recognition appeared in the history of
human knowledge. It occurred here as in so many places in the history of
human civilization that the simple is the late outcome of the complex.
Just as in technique the apparatus often began in a complex, cumbersome
way and then became steadily simplified, so it is with explanations. The
complex machinery of cosmic influences and obsessions by demons and
magnetic mysteries was at first necessary until the simple explanation
was found that all the results depend upon the working of the mind
itself. Yet in technique and explanat