with thyroid dominant constitutions talk fluently, rapidly, and
continuously. Their energy makes them doers, actors rather than
spectators. They get up early in the morning, are on the go all day
without surcease or fatigue, go to bed late, and often suffer from
insomnia.

Thyroid deficients, however, are definitely the opposite. They are
quite conscious of the limited reserve of energy at their command.
Also that they need plenty of refreshing sleep. Early to bed and late
to rise remains the leading maxim of health for them. In addition they
find it necessary to sleep during the day. Forty winks or more in
the afternoon makes a good deal of difference to them. Taciturn,
inarticulate, lazy, slow, tired, are the adjectives applied to them
by their friends as well as by their enemies. All because of an
insufficient or inefficient supply of the thyroid's iodine to their
cells. The mobility of energy in an organism is a measure of the
amount of active iodine in it. The physiologic synonyms for "energetic
and lazy" are "well-iodinized" and "poorly iodinized."

Sensitivity, the ability to discriminate between grades of sensation
or acuteness of perception is another thyroid quality. Just as the
thyroid plus is more energetic, so is he more sensitive. He feels
things more, he feels pain more readily, because he arrives more
quickly at the stage when the stimulus damages his nerve apparatus.
The electric conductivity of his skin is greater, sometimes a hundred
times greater, than the average. Conversely the thyroid deficient type
has a low discriminative faculty. Galton has recorded that idiots
hardly distinguish between heat and cold and that their sense of pain
is so obtuse that some of the more idiotic seem hardly to know what it
is. Cretins may moan but never shed tears.

Energy and sensitivity in an individual should direct attention to the
thyroid element predominating in his composition. Lack of energy and
insensitivity to the degree of thyroid insufficiency in their make-up.

MEMORY, JUDGMENT, AND POISE

In between sensitivity and energy, the sensation and the reaction,
comes a passage of the stimulus through the gauntlet of the stored
past experience of the individual known as memory. Many hypotheses
have been advanced by philosophers, psychologists and physiologists to
explain the phenomenona of memory. To conceive of memory materially
at all one must admit some sort of memory trace as the basis for the
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