anation; yet it is in itself important,
complicated, and difficult. Of course, it may be easy to separate the
complex content into some big groups of facts, to point out that this is
a memory idea and this an imaginative idea and the other an abstract
idea, and this a perception and that a feeling, this an emotion and that
a volition. But such clumsy first discrimination does not go further,
perhaps, than does the naturalist's, who tells us that this is a
mountain and that a tree, this a pond and that a bird. The real
description would demand, of course, an exact measurement of the height
of the mountain and the geological analysis of its structure, or an
exact classification of the tree and the bird, with a complete
description of their organs, and in each organ the various tissues have
to be described, and in each tissue the various cells, and the
microscopist goes further and describes the structure of the cell.
Certainly in the same way the psychologist has to go on to resolve every
one of those complex structures; he has to examine the mental tissues
and the mental cells of which a volition or a memory idea or a
perception are composed. And while he cannot use a microscope for these
mental elements, yet his studies may cause elements to appear which the
naive observation remains entirely unaware of.

Perhaps he finds in his consciousness the perception of the table before
him which lingers for a little while in his mind. He finds no difficulty
in analyzing it into color sensations and tactual sensations; and yet he
is aware of so much more in it. The table, for instance, has form for
him and he may find that these form perceptions involve the sensations
of the eye movements which he makes from one corner of the table to the
other; he may find that if the idea lasts in him, he becomes aware of
the time by sensations of tension; he finds that in his perception of
the table lies an idea of its use, and he discovers that that is made up
of elements which are partly memory reproductions of earlier
impressions, partly sensations of movement impulses; he also finds that
the table feels smooth, and he discovers by his analysis that this
impression of smoothness results from a special combination of tactual
sensations and movement sensations; and again those movement sensations
he analyzes further into sensations of muscle contraction and sensations
of pressure in the joints and sensations of tension in the tendons.
Before