ticular _use_ of what you have comprehended.
The original mental impression has been _fully developed_ because you
employed all three processes. If you had not completed the cycle of
development, you would have given your mind only partial exercise with
what you heard.

In order to become a master salesman, you must _take in_ many
impressions, perceive their _significance to you_ and how you can make
use of them, then _act_ on your comprehension of what you have learned.
There are countless failures in the world who might have been successes
if they had not stopped their possible mental development at the first
or second stages.

A man might know an encyclopedia of facts, but be a failure.

He might comprehend how to use his knowledge, and still be a failure.

_Success comes only to the man who acts most effectively on what he
knows_.

[Sidenote: Right Practice Of the Three Processes]

In order to secure quick and effective results, the _practice_ of the
three necessary processes of development should be:

First, _definitely conscious_. You need to _know just what_ quality you
want to develop in yourself.

Second, _discriminative_. You must learn the _differences_ between what
you _want_, and what you _don't want_ to develop in particular.

Third, _restrictive_. It is necessary that in your training to develop a
certain quality, you _concentrate_ your practice on the respects in
which this particular quality differs from other qualities.

Most of us are pretty _definitely conscious_ of what we want. We know
just the qualities we would like to have. But very few people employ
most effectively the _discriminative-restrictive methods of training_ in
their processes of development.

[Sidenote: Importance of Differentiation]

It is impossible to develop a particular quality fully if you only
recognize its _likenesses_ to other qualities. _Real mental development
is accomplished only as a result of the recognition of differences_.
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