poken. But a little exercise of his brain
in transmitting again the sound of his native tongue will quickly
stimulate his mind with the renewed supply of this particular mental
food to which it formerly was accustomed. In a few weeks he will use
the old language naturally; whereas another man, who never had spoken
it, would require years to build up such full knowledge from a start of
complete ignorance of the language.

Evidently, too, a _weak_, undeveloped brain center would be incapable of
receiving _strong_ mental impulses from its coordinated mind center, and
of transmitting them in full strength to the particular muscles governed
by that mind center. This is why, if a man's _brain center_ of courage
is undeveloped, even the most courageous _thoughts_ will not make his
body _act_ bravely. His legs may run away against his will to fight. The
physical instrument of his mind (his brain), and also certain associated
sets of muscles, must be sufficiently exercised in the _action_ of
courage to build up within him the _physical structure_ of fearlessness
that will be instantly responsive to a _mental attitude_ of bravery.

[Sidenote: Right Exercise for Development]

If for any reason the brain instrument is weak or undeveloped, it can
handle only weakly either in-coming messages to the ego from the senses,
or out-going impulses from the mind to the muscles. So, because of this
undeveloped brain instrument, the full capability of neither the inner
nor the outer man can be built up and put to use. Obviously, therefore,
if one is ambitious to succeed, he needs to know and to practice the
_coordinated mind-brain-muscle exercises_ that will increase the
quantity and better the quality of his man capacity. Since he is a
"many-minded, many-bodied" man, _general_ physical and mental exercise
will not develop the _particular_ qualities required to assure his
success. Each and every mind-brain-muscle set must be built up
individually by _specific_ exercises which strengthen _that particular