e
similar to the one which chemistry made when it found that the same
elements which are part of the inorganic substances are also the only
possible elements of the organic world.

From a strictly psychological standpoint, the ideas and the not-ideas
contain thus nothing but sensations. Their grouping, their shading,
their combination, their succession decide whether we have before us a
perception or an imagination, a volition or an emotion. What are we
ourselves then for the psychologist? Evidently we ourselves belong also
to the inner experiences which we know; and psychology has succeeded in
analyzing this idea of our own self just in the same way as it analyzes
our idea of the moon. In this analysis, psychology finds its idea of the
self as a content of consciousness crystallized about the sensations
from the body. Every one of our bodily activities is represented in our
consciousness by movement sensations, and these sensations form the core
of the complex aggregate which develops into the idea of ourselves.
Organic sensations from our inner organs, pain sensations and pleasure
sensations fuse with the movement sensations, and the whole complex
shapes itself slowly into the idea of the personality of the self in
contrast to the idea of other personalities. We ourselves are for
ourselves a complex combination of sensations; and yet all our feelings
and emotions and volitions are only a part of it. Psychology thus
necessarily considers those experiences of feeling and will and
character simply as changes in the midst of that central experience of
personality which is itself made up of bodily sensations. Each bit of
will and emotion must be decomposed into its finest elements. There is
no passing mood, and no floating half-thought in our mind, no dream and
no intuition, no slightest change of attention, no instinct and desire
which cannot be analyzed thus into its sensation elements or rather
which must not be analyzed, if we are to describe it at all, and that
means if we are to give a psychological account. Psychology is endlessly
far from this ideal to-day. It has been claimed, not without justice,
that psychology has reached to-day only the level which physics attained
in the seventeenth century; but psychology must insist that its ideal
lies in this direction. No one takes a real psychological view of the
human mind who does not understand this endless complexity of the
material, and who does not see that even th