n acquired during a state of
fatigue is also much less than under a more healthy and
resilient condition of the organism.

The point of fatigue varies among different individuals and
in consequence the conditions of habit-formation vary. But
some conditions remain constant. For instance, in experiments
with memory tests (memory being a form of habit in
the nervous system), material memorized in the morning
seems to be most rapidly acquired and most permanently
retained.

The age and health of the individual also are important
factors in the capacity to learn, or habit-formation.
Conditions during disease are similar to those obtaining during
fatigue, only to a more acute degree. The toxins and poisons
in the nervous system at such times operate to prevent the
formation of new habits and the breaking of old ones. For
while the synapses (nerve junctions) may offer high resistance
to the passage of a new stimulus, they will lend themselves
more and more readily to the passage of stimuli by which
they have already been traversed.

That the age of the individual should make a vast difference
in the capacity to acquire new habits and to modify old ones
is obvious from the physiology of habit already described.
When the brain and nervous system are both young, there are
few neural connections established, and the organism is plastic
to all stimuli. As the individual grows older, connections
once made tend to be repeated and to be, as it were,
unconsciously preferred by the nervous system. The capacity to
form habits is most pronounced in the young child in whose
nervous structure no one action rather than another has yet
had a chance to be ingrained. The more connections that are
made, the more habits that are acquired, the less, in a sense,
can be made. For the organism will tend to repeat those
actions to which it has previously been stimulated, and the
more frequently it repeats them the more frequently it will
tend to. So that, as William James pointed out, by twenty-five
we are almost literally bundles of habits. When the
majority of acts of life have become routine and fixed, it is
almost impossible to acquire new ways of acting, since the
acquisition of new habits seriously interferes with the old, and
old habits physiologically stay put.

HABIT AS A TIME-SAVER. This fact, that habits can be
acquired most easily early in life, and that those early acquired
become so fixed that they are almost inescapable, is o