CHAPTER 30 • BIOLOGY AND HEALTH 



Public health is purchasable; within certain limitations, a community can determine its own 

 death rate. — Hermann Biggs, health officer. New York City, 1911 



1 What is the best way of keeping well? 



2 Why must there be sickness? 



3 Can anything in the food or water or air make us sick? 



4 Can the lack of anything in the food, water or air make people 



sick? 



5 Can things get into the body in other ways than through the 



mouth or nose, and make people sick? 



6 How can we be sure that the "evil eye" or malicious wishing 



does not cause disease? 



7 Can all diseases be prevented? 



8 How can we tell that new ideas about sickness are better than 



old ones? 



9 What disease can be cured by purely mental methods of healing? 

 10 Why must there be so many specialists? 



People have always wondered what made them sick. This is no idle curi- 

 osity. The correct answer may solve an important practical problem, namely: 

 How can sickness be cured when it strikes? Men have dared to think even 

 more boldly: How can we prevent sickness from striking? 



Early ideas about disease were very much confused. It is easy enough to 

 make guesses about the causes of a particular disorder or of disease in general. 

 But there are always more false guesses than right ones; and in the past there 

 was no way of checking them, to find which was right. How can we tell that 

 the newer ideas and practices about keeping people well are more dependable 

 than earlier ones? Why do doctors change their theories about disease? Why 

 do not doctors always agree about what to do? 



How Important Is Sickness? 



How We Measure Sickness^ Ordinarily we become interested in health 

 only when we are in pain or disabled, or when we see others suffering. On an 

 average, six millions of the population of the United States are suffering each 

 day from disabling sickness. Some of us do not lose a day through sickness for 

 years at a stretch. Others are aiUng a large part of the time. The average 

 time out from work or from school — or from play — is about ten days a year. 



Health-department reports usually deal with communicable diseases only. 

 Another way of measuring the health of populations is to compare their aver- 

 age length of life or their death rates (the number of deaths in one year for 



iSeeNo. 1, p. 638. 

 605 



