Introspective observation of pre-criminal states of mind by so-called normal persons reveals that in many of them there is an impairment of reason and will power, in others an exaltation amounting almost to hysteria.  What are these but endocrine states of the cells, experimentally reproducible by increasing or decreasing the influence of the thyroid, the adrenals, the pituitary?  Crimes of passion may be traced in no small part to disturbances of the thyroid.  A psychologic examiner of a Pittsburgh court, interested in the subject, has found an enlarged thyroid in over ninety per cent of delinquent girls.  Similarly, crimes of violence may be ascribed to a profound break in the adrenal equilibrium.  Criminal tendencies in women during menstruation and pregnancy, periods of deep-seated mutation in the internal glandular system, have long been noted.  A kleptomania, uncontrollable desire to steal, confined to the duration of pregnancy alone, has been described.  We have seen how the thymocentric, especially if he possesses a small bony case for his pituitary, is predisposed to crime.  A recent study of twenty murderers in the State of West Virginia showed them all to have a persistent thymus and the thymocentric constitution.  A study of the recidivists, those who return for second and third offences, in one institution, disclosed that a large majority had a subnormal temperature and an increased heart and breathing rate.  These are endocrine-controlled functions.  Conduct, normal or abnormal, being the resultant of the conflict of conscious and subconscious impulses and inhibitions, the internal secretions as controllers of the susceptibility of the brain cells to impulses and inhibitions, must be held accountable for a portion at least of the chemical reactions behind crime.

It is possible, by X-ray treatment of the thymus, to cause it to shrink to more normal proportions.  It is possible, by feeding various glandular extracts, to correct deficiencies or excesses of their function, and so to remedy the underlying basis for a criminal career.  Here and there work of this kind has been successfully carried out in selected instances.  What a suitable drive upon the whole matter would yield in happiness to the individual and dollars and cents to society, time alone will show.

CHAPTER XIII

THE EFFECT UPON HUMAN EVOLUTION

The ubiquitous and deep-seated influence of the internal secretions upon life and personality comprises but a fraction of what is known, and only a hint of what is to become known.  There is an endocrine aspect to every human being and every human activity, normal and abnormal, internal process and its external expression, regulated by laws of which we are beginning to catch a glimpse.  Their control promises us now a dominion over the most intimate and inaccessible recesses of our lives in a way comparable only to the control we now exercise over the forces and energies once revered as the instruments of the gods—­light, heat, magnetism, electricity.  We have learned how to control and change our environment.  We are now learning, endocrine research is now discovering, how to control and change ourselves.