to you freely by the very instances
to which I have just referred. But technical clearness as to such
topics is hard to attain. Allow me, then, to insist with some care
upon matters which are as influential in moulding our whole destiny as
they are commonly neglected in our discussions of the problems of life
and of reality.

_Man can attend to but a very narrow range of facts at any one
instant._ Common-sense observation shows you this. Psychological
experiment emphasises it in manifold ways. Listen to a rhythmic series
of beats--drum beats--or the strokes of an engine, or the feet of
horses passing by in the street. You cannot directly grasp with entire
clearness more than a very brief sequence of these beats, or other
sounds, or of rhythmic phrases of any kind. If the rhythm of a
regularly repeated set of sounds is too {260} long, or too complex, it
becomes confused for you. You cannot make out by your direct attention
what it is at least until it has by repetition grown familiar. Let
several objects be brought before you at once. You can attend to one
and then to another at pleasure if only they stay there to be attended
to. But only a very few distinct objects can be suddenly seen at once,
and at a single glance, and recognised, through that one instantaneous
presentation, for what they are. If the objects are revealed to you in
the darkness by an electric spark, or are seen through a single slit
in a screen that rapidly moves before your eyes--so that the objects
are exposed to your observation only during the extremely brief time
when the slit passes directly between them and your eyes--this limit
of your power to grasp several distinct objects at once, upon a single
inspection, can be experimentally tested. The results of such
experiments concern us here only in the most general way. Enough--as
such tests show--what one may call the span of our consciousness, its
power to grasp many facts in any one individual moment of our lives,
is extremely limited. It is limited as to the number of simultaneously
presented facts that we can grasp at one view, can distinguish, and
recognise, and hold clearly before us. It is also limited with regard
to the number and the duration of the successive facts that we can so
face as directly to grasp the character of their succession, rhythmic
or otherwise.

{261}

Now this limitation of the span of our consciousness is, I repeat, an
ever-present defect of our human type of cons