PAET V 



THE PRESERVATION OF HEALTH 



CHAPTER XXIV 

 HEALTH AND DISEASE 



484. Health, in man, is that condition of the organism 

 in which all the various parts composing it perform their 

 functions perfectly, so that the largest amount of the best 

 work of which the being is capable is performed easily 

 and without discomfort. Health is attended with a feel- 

 ing of buoyancy, vigor, and happiness. Disease is the 

 result of disordered action in some one or more parts of 

 the organism, usually long-continued and affecting more 

 and more the various vital processes. 



Many of the ways in which persons are accustomed to 

 injure the health by inattention to hygienic rules, or by 

 violations of them, have been alluded to in preceding 

 chapters. Incorrect habits of life are the direct cause of 

 many diseases, and indirectly cause many more by weak- 

 ening the organs, and preparing the system to yield 

 readily when exposed to the influences of specific disease. 



485. Bacteria. It is now known that several forms of 

 disease arise from the growth and multiplication, within 

 the body, of certain microscopic forms of life called bac- 

 teria, or bacilli, or microbes, or germs. These are living 



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