_Factors in Human Nature._--It must never be forgotten that gambling excitement or the spirit of undue emulation exists in all classes of men--in biological investigators as well as others--and it needs guidance or restraint. The German officer Reizenstein felt keen remorse for the murder of his beautiful Irish mare Lippespringe, yet he and his companions tortured thirty horses to death under the temporary insanity of intense rivalry. But it was possible to bring public conscience to bear on this barbarity, and thus check the recurrence of any similar future aberration. So in biological research we see the disastrous effects of individual and national rivalry. They are shown in the contradictory results of false methods of observation, in the endless repetition of similar painful experiments, in the strife of conflicting theories, and in the practical failure of results obtained from the lower animals when applied to the human race. The moral sense of a noble profession may well be appealed to to create a conscience which shall check the present grave abuses of so-called research. CHAPTER VII _Prurigo Secandi_ Another serious ethical danger connected with unrestrained experiment on the lower animals is the enormous increase of audacious human surgery, which tends to overpower the slower but more natural methods of medical art and to divert attention from hygiene. This modern increase of surgery, entailing permanent mutilation, has received a special name, prurigo secandi, or cacoethes secandi. It prevails in France and in every country where no restraint is placed on animal experimentation,[17] or where the importance of not injuring the moral sense of students has not been recognised. The great increase in ovariotomy, and its extension to the insane is a notable result of this prurigo secandi. Dr. Chanu, in his carefully-prepared thesis of 1896, in exposing the grave abuse of this branch of surgery, estimates that there were 500,000 castrated women in France, and one in every 250 women throughout Europe. He finds the decrease of the birth-rate to coincide with the abuse of ovariotomy. ‘Dr. Chanu affirmed, before a jury unable to refute his assertion, that the abuse of ovariotomy has done more harm to France in ten years than the Prussian bullets did in 1870, and that the causes of the depopulation of France are closely allied to the practice of the castration of women.’ The prevention of disease in the organs of generation must be sought for persistently in improved education of the young--the male as well as the female--and in _just_ relations of the sexes. Of the same nature as the prurigo secandi of medical practice is the motive or source of much of the laboratory experimentation.