4 INTRODUCTION 



the efficient application of what we already know. Popular 

 ignorance of diseases, even such common ones as malaria and 

 syphilis, is nothing short of appalling. This ignorance is by 

 no means confined to the poorly educated masses; it is wide- 

 spread among educated, college-bred people, and, piteous as it 

 may seem, is characteristic of many professional men, among 

 them even physicians bearing good reputation. There are a 

 number of causes for this unfortunate condition. Many physi- 

 cians of the old school have been so busy or so unprogressive 

 that they have never attempted to add to or modify the knowl- 

 edge they had when they first took up the medical profession 20 

 or 30 years ago; people with erroneous or distorted views of 

 things publish their ideas in newspapers or magazines as authori- 

 tative statements, and thus unmeaningly mislead the enormous 

 number of people who swallow such newspaper articles without 

 even a flicker of hesitation; quack doctors, those hellish buz- 

 zards who prey upon the innate gullibility of the greater part 

 of the human race, willfully mislead and scatter at random the 

 seeds of misinformation which have held back the progress of 

 sanitation and health to a pitiful extent and have borne as their 

 fruit sorrow, misery and suffering; and, finally, such is the * 

 conservativeness, or rather imperviousness, of our species that 

 a new idea requires, often, not decades but centuries to penetrate 

 thoroughly the popular mind. It is nearly 60 years since Darwin 

 brought the theory of evolution into serious consideration and 

 showed the folly of belief in special creation, yet it is no exag- 

 geration to say that a very large majority of people at the present 

 time do not believe in evolution. It is 250 years since the idea 

 that living organisms do not spontaneously spring into exis- 

 tence from non-living matter was first promulgated, and nearly 

 60 years since the last vestige of possibility was torn from the 

 theory of spontaneous generation, yet even today the prev- 

 alence of such beliefs as that " horse-hair snakes " develop 

 out of horse hairs in water is nothing short of astonishing. It 

 is 120 years since Jenner proved the efficacy of vaccination 

 against smallpox, yet there exist at the present time numerous 

 anti-vaccination societies whose sole purpose is to denounce 

 vaccination as an impractical and illogical proceeding. How 

 can we expect popular belief in the mosquito transmission of 

 malaria which was demonstrated only 20 years ago! 



