The story of the evolution of the two types of control has many analogies.  When man ceased looking upon his surroundings as inhabited by spirits of good and evil, as he conceived himself, and discovered that they were composed of things malleable and analysable in his hands, he became their master.  When now he drops the old superstitions about himself as a spirit, an emulsion of a spirit of good and spirit of evil, and sees himself more and more clearly as the most complex of chemical reactions, regulated and determined as are the simple and complex chemical reactions around him, he will begin to rule and modify himself as he rules and modifies them.  Whether or not he will ultimately come to this final lucidity of thought and action, it behooves us to consider some of the uses to which our present knowledge might be put.

Since every step of the daily routine or adventure, from waking to sleeping, eating, drinking, marrying and giving in marriage, working, idling, fighting, playing, feeling, enjoying, sorrowing, every shade of emotion and nuance of mood, in short every phase of happiness and unhappiness, are endocrine episodes in the life history of the individual, the sphere of applications is as long and broad and deep as life itself.  Not only do the internal secretions open up before us the great hope—­that Life at last will cease to stumble and grope and blunder, manacled by the iron chains of inexorable cause and effect.  They provide tools, concrete and measurable, that can be handled and moved, weighed and seen, for the management of the problems of human nature and evolution.

Every department of human life, the questions of labor and industry, science and art, education, puericulture, international problems, crime and disease, may be illuminated.  War and Sex, those two master interests of mankind, may be understood and handled sympathetically as they have never before.  The reactions of man alone, and man in the crowd, will be clarified.  The red thread of individuality which runs through the woof and warp of all human affairs will be unraveled.

Inevitably, customs, morals, codes of procedure and practice, institutions, all those expressions of opinion which make conduct, all the currents which contrive the infinite variety of life, will be transmitted into another set of values.

A remoulding, a remodeling will take place all along the line.  Manifestly an unstable thymocentric should not be treated as a criminal, but treated in a sanitarium.  A masculinoid woman needs satisfactions not vouchsafed in the old “love, honor and obey” home.  How absurd it is to found codes of morality upon sermons or even the latest psychologies.  During the nineteenth century progress in physics and mechanics overturned traditions thousands of years had painfully toiled to erect.  What is to happen when man comes at last to experiment upon himself like a god, dealing not only with the materials without, but also with the very constituents of his innermost being?  Will he not then indeed become a god?  If he does not destroy himself before, that is surely his destiny.  For better or for worse, we possess now in the endocrines new instruments for swaying the individual as individual, and as related to other individuals, as a member of a type, family, nation, species and genus.