into the rest of the organism. Especially is this true if the
thought is associated with some emotion. Emotion, as we shall
discuss it later, is at least in large part a bodily reaction, a
disturbance in heart, lungs, abdominal organs, blood vessels,
sympathetic nervous system, endocrines, etc. The effect of
thought and emotion upon the body, whether to heighten its
activity or to lower its activity, is, from my point of view,
merely the effect of one function of the organism upon others. We
are not surprised if digestion affects thinking and mood, and we
need not be surprised if thought and mood disturb or improve
digestion. And we may substitute for digestion any other organic
function.

As a working basis, substantiated by the kind of proof we use in
our daily lives in laboratories and machine shops, we may state
that mind, character and personality are organic in their origin
and are functions of the entire organism. What a man thinks, does
and feels (or perhaps we should reverse this order) is the result
of environmental forces playing upon a marvelously intricate
organism in which every part reacts on every other part, in which
nervous energy influences digestion and digestion influences
nervous energy, in which enzymes, hormones, and endocrines engage
in an extraordinary game of checks and balance, which in the
normal course of events make for the individual's welfare. What a
man thinks, does, and feels influences the fate of his organism
from one end of life to the other.

We have not adduced in favor of the organic nature of mind,
character and personality the facts of heredity. This is a most
important set of facts, for if the egg and the sperm carry