[Sidenote:  The Process Of Growth]

Returning to the comparison of Burbank’s methods with man development, we perceive again how the principle of discriminative-selective training is applied to accomplish the growth of certain characteristics needed to assure a man’s success.  The plant wizard in his initial tests gave to his undeveloped prune trees particular food and conditions and treatment selected for the purpose of imparting specific qualities of deliciousness.  A prune somewhat improved in deliciousness was the first result.  Then from the product of that improved prune he started another cycle of development.  He fed the selected food of deliciousness to the improved prune tree, and a fruit more delicious resulted.  His work was simply plant breeding by the discriminative-restrictive method.  Brain breeding is a similar process of particularized, cumulative development.

[Sidenote:  Begin With Specific Training of The Outer Man]

All the foregoing rather complicated explanation of “psychological processes” has seemed necessary to make a clear impression of the right training methods for building within you any quality you need to assure your success.  You must begin by training your outer man.

You can develop a particular mind-brain center (such as the center of courage) only by the discriminative-restrictive training of those portions of your body which are directly related in activity and responsiveness to that mind-brain unit of the multiplex YOU.  Training of any other set of muscles will not develop the particular mind-brain center you want to build up, and would be a wrong procedure.

You should begin with specific training of particular sets of sensory muscles because, as we have seen, that is the natural order of the process of growth.  It is how you began to learn everything you know.  You can increase and improve your present limited, conscious knowledge most effectively by taking into your mind from your trained particular senses more and better impressions than you ever have taken in before.

[Sidenote:  Developing Persistence]

Suppose your success has been hindered by your lack of persistence.  You need to develop that quality in particular.  Let us see how the discriminative-restrictive principle should be applied specifically to assure you of building persistence within yourself.

First it is necessary that you discriminate between this one quality and all others; especially between it and the quality of determination.  Very different training methods are required to develop persistence and determination respectively.  When you are just “determined” to do a thing, your jaw muscles, your arm and back muscles, perhaps all your commonly known muscles, will be hardened as long as you remain determined, but no longer.  They will relax when the occasion for determination has passed.  The habit of instantly tensing your muscles temporarily whenever you need to be determined will very greatly strengthen and improve the efficiency of your brain-mind center of determination. But that temporary hardening of your muscles will only slightly affect the development in you of characteristic persistence.