In Brief 



A living being acts as a unit, or whole, not as a mere collection of parts. 



Specialized cells or tissues may be grown in the laboratory; in a culture 

 they are able to grow and multiply, but they are not able to supply them- 

 selves with food, air, or water. They can continue to live only so long as 

 their needs are met by laboratory attendants. 



We cannot understand the parts of a human body, or of the body of any 

 other living thing, except in terms of the whole living organism, in which 

 every happening may influence every part. 



In the larger plants and animals, the complete unity of an organism is 

 observable in its every action, at every stage in its development. 



As diiTerentiation of parts occurs in the development of an animal, dif- 

 ferent cells act in somewhat different ways; yet the whole mass of cells 

 behaves as one organism. 



Some of the functions or activities of specialized cells are more general 

 than others; thus an organism can continue to live if certain parts are 

 destroyed, but not if other parts are destroyed. 



The more elaborate and specialized an organism is, the more of its body 

 consists of specialized accessory organs and tissues, and the more of it con- 

 sists of nonliving structures. 



Throughout the ages there have arisen various beliefs and explanations 

 for sickness which later generations ridiculed as foolish. But we are unable 

 to prove or disprove these beliefs, as each involves, to some extent, reliance 

 on supernatural beings or forces, with which we cannot experiment. 



Illness results when the unity of an organism and the effectiveness of its 

 adjustments are thrown out of balance by any of a variety of events. 



The chemical condition of the body fluids influences mental processes, 

 as well as others. 



Various habits of feeling and thinking and acting influence the internal 

 adjustments of the body and may bring about an organic imbalance. 



The body works as a whole so far as it is controlled by a single purpose 

 or desire. 



We distinguish as work of the "mind" that control which is purposive, 

 or conscious, or voluntary, in contrast to. that unconscious control which 

 automatically adjusts the body both to internal and to external changes. 



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