iety of
complex situations he meets in daily life. A monkey exists
with fairly fixed native tendencies to act. But civilization
could never have developed if in man new ways could not be
acquired to meet new situations, and if these new ways could
not be retained and made habitual in the individual and the
race.

TRIAL AND ERROR AND DELIBERATE LEARNING. Whenever, as
happens a large number of times daily in the life of the average
man, old ways of response, inborn or formerly acquired,
are inadequate to meet a new situation, there are two methods
of acquiring a new and more adequate response. One is the
method of trial and error, already discussed, whereby animals
and humans try every possible instinctive response to a
situation until one brings satisfaction and is retained as a habitual
reaction when that situation recurs. The other is a delay in
response, during which delay reflection, a consideration of
possible alternatives, and a conscious decision, take place.
The technique of this latter process will be discussed more
specifically in the next chapter.

Whether acquired by trial and error, or through reflection,
learned acts are, the first time they are performed, frequently
imperfect, only partly effective, and performed with some
difficulty. With successive repetitions their performance
becomes more rapid, more immediate, and more adjusted to
the specific situation to be met. And as they become more
familiar responses to familiar stimuli they cease to be
conscious at all. They are performed with almost as little
difficulty or attention as normal breathing.

SOME CONDITIONS OF HABIT-FORMATION. The acquisition of
habits is so important in the education of human beings that
the conditions under which they can be acquired and made
permanently effective have been closely studied. From
experiments certain fundamental conclusions stand out. A
habit is acquired by repetition, and the "curves of learning"
show certain recurrent features. In the first few repetitions
of an acquired activity, there is progress in the rapidity,
effectiveness, and accuracy with which the response is made.
There is, up to a certain point, an almost vertical rise in the
learning curve. After varying numbers of repetitions, depending
somewhat on the particular individual, there occur
what are known as "plateaux," during which no progress in
speed or accuracy of response is to be observed. In experiments
with the learning of typewriting,