individual is reached as easily or as soon as has been believed.

There are certain aids to improvement which must be used in order that
the best results may be obtained. Some of them have already been
discussed and others will be discussed at a later time, so they need
only be listed here, the right physiological conditions, the proper
distribution of the practice periods, interest in the work, interest in
improvement, problem attitude, attention, and absence of both excitement
and worry.

Habits have been treated in psychology as wholes, just as if each habit
was a unit. This has been true, whether the habits being discussed were
moral habits, such as sharing toys with a younger brother; intellectual
habits, such as reading and understanding the meaning of the word "and";
or motor habits, such as sitting straight. The slightest consideration
of these habits makes obvious that they differ tremendously in
complexity. The moral habit quoted involves both intellectual and motor
habits--and not one, but several. From a physiological point of view,
this difference in the complexity of habits is made clear by an
examination of the number of neural bonds used in getting the habit
response to a given situation. In some cases they are comparatively
few--in others the number necessary is astonishing. In no case of habit
will the bonds used involve but a single connection.

Just what bonds are needed in order that a child may learn to add, or to
spell, to appreciate music, or to be industrious, is a question that
only experiment and investigation can answer. At present but little is
known as to just what happens, just what connections are formed, when
from the original tendency towards vocalization the child just learns to
say the word "milk," later reads it, and still later writes it. One