August 14, lOOS] 



SCIENCE 



197 



although the "meat" of to-day may be 

 largely cereals, vegetables and fruit. 



We need thus to broaden and deepen our 

 knowledge of the human organism and its 

 evolution before we seek to modify it or 

 its behavior towards the environment. And 

 so, too, in our studies of the environment 

 for health's sake, or for preventive medi- 

 cine, we must begin with the broadest ideas. 

 For we are here dealing with that other 

 and vastly greater hemisphere of human in- 

 terest, which, taken together with the hu- 

 man organism, makes up nothing less than 

 the whole known universe. We may even 

 define the environment as that part of the 

 universe not ourselves— a conception which, 

 made dynamic by the interaction of the two 

 reciprocal factors, organism and environ- 

 ment, becomes almost sublime. How deli- 

 cately the human organism is attuned to its 

 environment we realize when we consider 

 that wonderful rhythm which we call our 

 sleep and our awaking, and that other 

 rhythm of hibernating plants and animals 

 which is the response to seasonal rather 

 than nocturnal darkness. The more inti- 

 mate relations of climatology and public 

 health have yet to be worked out, but no 

 one can doubt their fundamental impor- 

 tance, and Major Woodruff's main conten- 

 tion, in his interesting book on the effects 

 of tropical light on white men, is certainly 

 correct, as any one knows who has ever felt 

 the tropical sun, or even suffered severely 

 in middle life from sunburn. 



The increasing call for health which, as 

 I have shown, has its origin in the convic- 

 tion that life is Avorth living, especially if 

 it be normal, healthy life, finds strong sup- 

 port on every hand, but especially in the 

 conservation of human energy; in greater 

 humanitarianism ; and in economic and 

 moral efficiency. There is a kind of con- 

 servation of human matter and energy as 

 truly as there is of physical matter and 

 force. I hold no brief for vitalism ; but 



our physical human energy is subject to 

 laws of dissipation as surely as is that of 

 the sun, and that man who expends his 

 thought and energy upon himself and his 

 ills, dissipates and loses his stock of energy 

 available for other and better purposes. 

 On the other hand, we must not forget that 

 many invalids and persons in poor health 

 have been heavy contributors to the happi- 

 ness and welfare of the world. As ex- 

 amples I need only mention the names of 

 Charles Darwin and Robert Louis Steven- 

 son. 



The call to health has humanitai-ian as- 

 pects. Is it a light or a small affair to 

 postpone premature death, or to avoid sick- 

 ness, and thereby postpone or avoid the 

 pain, the sorrow and the weeping of those 

 who would mourn? Is it not a kind of 

 cruelty to allow infected water or milk to 

 carry into happy homes the germs of ty- 

 phoid or scarlet fever? If a thief in the 

 night should wound and kill, as milk-borne 

 typhoid often does in a family of children, 

 should we not call him cruel? Sickness 

 and deaths from carelessness are not, per- 

 haps, as repugnant or as cruel as those 

 from malice or robbery, but the actual 

 effects upon the family and the social or- 

 ganism are much the same. 



As for moral considerations involved in 

 the present-day call to public health, we 

 need only to think of the peevishness or 

 the ciuerulousness of invalidism, which 

 often rises, or falls, into selfishness so gross 

 as to be pathological; of the dyspepsia, 

 with its moral as well as physical torments 

 to patients and their friends; or of those 

 degenerated and perverted human speci- 

 mens which disease sometimes produces, to 

 show that here also we can no longer at- 

 tribute to devils what often proceeds from 

 disease, and that the call to health and 

 prevention for morals ' sake is loud and 

 urgent. 



On the economic side, the call for health 



