never stands still. It continually moves along, and at no two moments
is it exactly the same. This results in a condition whereby an idea
which is at one moment at the centre cannot remain there unless it
takes on a slightly different appearance from moment to moment. When
you attempted to fix your attention upon the letter O, you found a
constant tendency to shift the attention, perhaps to a variation in the
intensity of the type or to a flaw in the type or in the paper. In view
of the inevitable nature of these changes, you see that in spite of
your best efforts you cannot expect to maintain any object of study
inflexibly at the centre of attention. The way to do is to manipulate
the object so that it will appear from moment to moment in a slightly
different light. If, for example, you are trying to concentrate upon a
rule of English grammar long enough to memorize it, do not read it over
and over again, depending solely upon repetition. A better way, after
thoroughly comprehending it, is to think about it in several relations;
compare it with other rules, noting points of likeness and difference;
apply it to the construction of a sentence. The essential thing is to
do something with it. Only thus can you keep it in the focus of
attention. This is equivalent to the restatement of another fact
stressed in a previous chapter, namely, that the mind is not a passive
thing that stands still, but an active thing. When you give attention,
you actively select from a number of possible objects one to be clearer
than the rest. This selection requires effort under most conditions of
study, but you may be cheered by the thought that as you develop
interest in the fields of study, and as you develop habits of ignoring
distractions, you will be able to fixate your attention with less and
less effort. A further important fact is that as you develop power to
select objects for the consideration of attention, you develop
simultaneously other mental processes--the ability to memorize, to
economize time and effort and to control future thoughts and actions.