f itself. We may say, then, that in order to be able
to do a thing with little or no attention, we must give much attention
to it at first.

Another important factor in habit-formation is pleasure. The act which
we are practicing must give us pleasure, either while we are doing it or
as a result. Pleasurable results hasten habit-formation. When we
practice an act in which we have no interest, we make slow progress or
none at all. Now the elements of interest are attention and pleasure. If
we voluntarily attend to a thing and its performance gives us pleasure,
or pleasure results from it, we say we are interested in it. The secret
of successful practice is interest. Repeatedly in laboratory experiments
it happens that a student loses interest in the performance and
subsequently makes little, if any, progress. One of the biggest problems
connected with habit-formation is that of maintaining interest.

A factor which prevents the formation of habits is that of exceptions.
If a stimulus, instead of going over to the appropriate response,
produces some other action, there is an interference in the formation of
the desired habit. The effect of an exception is greater than the mere
neglect of practice. The _exception opens up another path_ and tends to
make future action uncertain. Particularly is this true in the case of
moral habits. Forming moral habits is usually uphill work anyway, in
that we have instincts to overcome. Allowing exceptions to enter, in the
moral sphere, usually means a slipping back into an old way of acting,
thereby weakening much the newly-made connection.

In any kind of practice, when we become fatigued we make errors. If we
continue to practice when fatigued, we form connections which we do not
wish to make and which interfere with the desired habits.

=Economy of Practice.= The principles which we have enumerated and
illustrated are fairly general and of universal validity. There are
certain other factors which we may discuss here under the head of
economical procedure. To form a habit, we must practice. But how long
should we practice at one time? This is an experimental problem and has
been definitely solved. It has been proved by experiment that we can
practice profitably for as long a time as we can maintain a high degree
of attention, which is usually till we become fatigued. This time is not
the same for all people. It varies with age, and in the case of the same
person it varies at differe