on is needed, you should train your _muscles_ to
harden _in coordination_, and thus to support your mental determination
by the complementary _physical suggestion_ of the same quality.

You do not need to use determination _all the time_; so it will be
sufficient if your muscles are taught to be _quickly responsive_ to
determination of mind on any occasion. (You know it helps you to carry
out a resolution if you stiffen your body at the moment you make up your
mind to do a thing, but _continued_ stiffness of the body in
determination would be a strain likely to weaken your power of action
unless backed by a tremendous, stored-up reserve strength of muscles.)
Begin your practice for the development of determination, then, by
training your muscles to tauten the instant you think determinedly. Your
brain-mind center of determination will also be strengthened by the
exercise that builds up the supporting habit of muscle action in
coordination. Millions of men have failed in life because their
determined thoughts were not reenforced by stiffened backbones.

[Sidenote: Discrimination Between Determination and Persistence]

Now let us discriminate between muscle training to develop the
characteristic of _persistence_ and the training already described for
the building of determination. In order to strengthen your persistence,
you must transmit through the distinct brain center of persistence to
the corresponding mind center, the impression of muscles _permanently
developed in firmness_, not just capable of temporary hardening on
occasion.

The _characteristically persistent_ man has gradually developed his
lax-muscled, sagging, baby chin into a jaw that is habitually firm,
whether or not he happens to be determined to do anything at a given
moment. His muscles do not sag utterly, even when he is asleep. He
probably wakes up in the morning with his teeth clenched. So, whenever
his coordinated brain-mind center perceives that the quality of
persistence is required, and starts to apply it,