Personality embraces much more than merely the psychic attributes.  It is not the least important of the lessons of endocrine analysis that there is no soul, and no body, either.  Rather a soul-body, or body-soul, or the patterns of the living flame.  The closer tracking of the internal secretions leads us into the secrets of the living flame, why it lives, and how it lives, the strange diversities of its colorings and music and the odd variations in its energy, vitality and longevity.  Why it flickers, why it flares and glares, spurts, flutters, burns hard or soft, orange-blue or yellow.

The medieval scholiasts, who fought as fiercely about names as nations about territories, divided men into the sanguine, the bilious, the lymphatic and the nervous.  It was a pretty crude classification of different constitutions.  The endocrine criteria, more exact and concrete, divide them into the adrenal centered, the thyroid centered, the thymus centered, the pituitary centered, the gonad centered, and their combinations.

THE ADRENAL PERSONALITIES

An adrenal personality is one dominated by the ups and downs of his adrenal gland.  In the large, the curve of his life is the curve of secretion by this gland, both of its Cortex and medulla.  Such an adrenal personality is entirely normal, within the definition of the normal as something not threatening the duration of life, nor comfortable adaptation to it.  So are the other glandular types.  No sharp line can be drawn between the normal and the abnormal in any case, the borderland is wide, the transitions many.

The skin is one of the chief clues to the adrenal personality.  The relation between the adrenal and the skin dates way back in the evolutionary scale, for adrenalin has been isolated directly from pigment deposits in the epidermis of frogs.  Skin pigment bears a direct relation to the reaction of the organism to light, especially the ultraviolet rays, to the radiation of heat, and hence to the fundamental productions and consumptions of energy by the cells.  So the gland of energy for emergencies writes its signature always all over the skin.

In an adrenal personality, the epidermis is always slightly, somewhat, or deeply pigmented.  The pigmentation is due to a dark brown deposit lightly or thickly scattered over the skin.  With the general diffuse pigmentation or darkening there are often the black spots, the pigmented birth marks, or the lighter ones of freckles.  The latter signify some permanent or transitory adrenal inadequacy in the past, ante-natal or post-natal, of the individual, and presage the same in his future.  These spots have been frequently observed to appear after an attack of diphtheria or influenza.  There seems to be more tuberculosis among those who have them than those who do not.  We therefore say that diphtheria, influenza and tuberculosis stand out as adrenal-attacking diseases, which have a greater power to kill, cripple or hurt those with defective adrenal constitutions than others.