=Some Insanities Not of Hereditary Origin.--=Some alienists believe that self-poisoning known as _auto-intoxication_, due to improper elimination of poisons generated through faulty digestion or metabolism, if of long standing, may be not only a contributory but a more or less direct cause of insanity. About twenty per cent. of insanities of men living in cities and about fifteen per cent. of those living in the country seem to be directly related to the intemperate use of alcohol. The corresponding figures for women are seven per cent. and one per cent. respectively. General paresis or softening of the brain is probably invariably preceded by syphilis. About twenty-two and five-tenths per cent. of the first admissions to hospitals for the insane from city-dwelling men, and eight per cent. from men living in the country in the state of New York are cases of this kind of insanity. The corresponding figures for women are five and five-tenths per cent. and two and five-tenths per cent. respectively. =Importance of Heredity in Insanity Not Appreciated.--=We have already seen that heredity plays an important part in insanities. There can be little doubt that the tendency is to under-estimate rather than over-estimate its importance. Many cases said to be "caused" by mental strain such as those occasioned by domestic infelicities, business reverses and the like should in all probability be fundamentally attributed to something far more deep-seated than the more obvious cause. In many such instances there is little doubt that an inherent weakness in mental make-up exists which predisposes the individual toward mental breakdown. This is more apparent when one recalls that there are thousands of other individuals who undergo equally great or greater calamities without loss of mental balance. There are well-recognized types of mental disposition which later contribute to corresponding forms of insanity. In many instances the final catastrophe may be averted if the "peculiar" individual can be kept in good health and guided into right habits of thought. Undoubtedly certain infectious diseases, arterio sclerosis, various poisons in the blood, child-birth, and similar influences often enter as important contributory factors. In all cases of cure, however, we must face the fact that under existing conditions these mentally restored individuals are released into society without let or hindrance as regards their marital relations. CHAPTER IX CRIME AND DELINQUENCY