HEALTH AND DISEASE 327 



reveals many disorders that formerly went undetected, degenerative disease 

 is on the increase. It respects neither economic status nor age. Though its 

 incidence is greater among the old, its destructive effects progress more 

 quickly among the young. 



Its burden upon society is incalculable. Medical practice, by lowering 

 infant mortahty and by prolonging the lives of the physically inadequate 

 whom pathogenic agents otherwise would weed out, some authorities 

 charge, places an increasing weight on the shoulders of the physically fit. 

 In addition, chronic physical disorder must inevitably be accompanied by 

 chronic mental and moral disorder: where physical stamina is lacking the 

 will lacks power; and the process of digestion, is profoundly influenced 

 by the state of general health. Carrel, Hooton, and Price — to mention only 

 three men already named in these pages — agree in attributing much of the 

 adult insanity and criminality which fills our institutions, and much juve- 

 nile delinquency, to the mental and moral consequences of diseases of 

 physical degeneration. 



The next question, logically, is — What causes diseases of degeneration? 

 Many answers have been given — most of them tentatively. In the case of 

 some of these diseases — particularly cancer — no honest man would attempt 

 an answer on the basis of the knowledge at hand. In the case of cardio- 

 vascular disorders, for example, many answers have been given — the stress 

 and strain of modern life, infections, increased indulgence in smoking, 

 metabohc disturbances, dietary deficiencies. Diseases such as scurvy and 

 pellagra have definitely been traced to vitamin deficiencies. Rickets has 

 been unmistakably traced to calcium deficiency or disorder of the calcium 

 metabolism due to endocrine disturbances or deficiency of vitamin D, or 

 all three. Although clinical medicine has made great advances in recog- 

 nizing and classifying the symptoms of degenerative diseases, and has 

 achieved some success in alleviating their discomforts and in prolonging 

 the lives of their victims, therapeutic measures necessarily remain empirical 

 — processes of trial and error — because of the almost incredible complexity 

 of the disorders. 



Take — for one further example of the difficulties which the subject im- 

 poses upon medical science — arthritis, a common malady whose incidence 

 is increasing. Frequently, it has been attributed to infection, and many a 

 tooth has been extracted and many a tonsil removed in efforts to cure it. 

 But why should a focal infection cause arthritis in one man and the same 

 focal infection not cause it in another? 



This complexity undoubtedly is due in large part to the fact that the 

 dearth of knowledge obscures many simple relationships. It is the usual 

 experience in scientific inquiry that, as knowledge increases, relationships 

 that at first were baffling in their complexity become progressively more 

 clear and can often be reduced to relatively simple laws. However that 

 may be, medical science stands today, with reference to these clironic, con- 



