TO THE CAVENDISH LECTURE 



who fail and see how they are differentiated by environment and 

 parentage from the successful girls. ^Ve were checked by the 

 discovery that eight or ten years after a girl has left the schools, 

 and when it is kfiown, generally speaking, whether she will be a 

 useful member of society or not, all school and police records 

 have perished. The material is apparently too great in bulk to be 

 indefinitely stored. 



Now I ask again is it not better that material bearing on medico- 

 social problems should be handled by laymen than that it should 

 perish without contributing its quota to our knowledge ? 



If you suggest that it would be best that we created a new class 

 of 'laroo-f^uidripXiTiKoi — of medical mathematicians — I am wholly 

 with you ; this is undoubtedly the ideal of the future. It has been 

 to some extent the ideal of the past, for I rejoice to number 

 among those who have worked in my laboratory the Director of 

 the Pasteur Institute of India and the Medical Statistician to the 

 Lister Institute of London. But is its full realisation possible ? 

 You know how arduous is the five years' training in medicine, but 

 do you appreciate how equally arduous is the requisite training in 

 mathematics to be followed by at least a two years' training in 

 statistics ? Do not fancy for a moment that the medical lectures 

 on vital statistics in a course for the D.P.H. are of the least 

 service in view of the modern statistical calculus. Sir Francis 

 Galton, who is the father of the scientific treatment of medico- 

 social problems and the founder of the modern science of 

 eugenics, spent four years over medicine and four over mathe- 

 matics, and the result was simply that because he was not a 

 certified specialist in either study the medical world gave no 

 weight to his judgments, and the mathematicians denied he was 

 one of their number ! 



No, I am afraid the fully-trained and qualified 'laTpo-naOrjariKOQ 

 is a man wholly of the future. Few men can afford the years of 

 training, and after it is over the officials who hold the appointment 

 to the few posts, where he might be of inestimable value would at 

 present be blind to his merits. The immediate line of least 

 resistance appears to me not the fusion of statistician and public 

 health officer, but the entente cordiale of the two branches of 

 investigation. I am convinced that every officer of the public 

 health service who really appreciates the magnitude and impor- 

 tance of his work both for medical progress and with it for social 

 welfare, is, however unconscious he may be of Sir Francis 



