LECTURE   XVII

§ I. Development of Attention ; Passive and Active Appercep¬
tion. § II. Attention AND Will; Fluctuations of Attention.
§ III. Range of Consciousness; Formation and Division of
Rhythmical Series.

§ I

SIMULTANEOUSLY with the development of self-con-
consciousness, which we described in the previous lecture,
proceeds the development of another complex process,—that of
attention. The two developments are in many respects similar.
States of attention, like those of self-consciousness, present
certain external differences which may be regarded as opposites ;
though it is true that, to place the opposition in a clear light,
we must more or less neglect intermediate processes which
would enable us to pass from one to the other. For the
extreme cases, however theoretically possible, never actually
occur in the purity in which they can be obtained by analysis.
However, if we disregard the concrete for a moment, we shall
find evidence enough for the general possibility of the extreme
cases.

We saw that in every act of apperception there are two
principal conditions of the resulting effect,—first, the momentary
condition of consciousness, itself determined partly by external
influences, partly by those of its own earlier states which are
directly related to these influences, and therefore with greater
or less regularity associated with them ; and secondly, the
entire previous history of consciousness, which may operate in
the most various ways to alter the effect due to this momentary
state. You must not, of course, suppose that these two con¬
ditions are at work in the individual case in the sense of two
opposing forces.    That would be impossible.    For the earlier