Dependency 42 1 



decline of the human race, as overspeciaHzations in the past 

 were the undoing of their possessors. 



Dependency 



Much of the difiicuhy which we experience in assimi- 

 lating evolution to our habitual way of thinking comes from 

 our failure to recognize the various orders of aggregation 

 and the various " laws " which operate. Too often we at- 

 tempt to " explain " all experiences with a limited set of 

 laws or principles. Those who start out, for whatever reason, 

 with the assumption that explanations are to be in terms of 

 the end or purpose, find offensive the mechanistic approach. 

 Everybody recognizes that all events are contingent, every- 

 thing that happens depends upon something else; but the 

 direction in which one seeks for the significant contingencies 

 will determine his conclusions. Various attempts to under- 

 stand the processes in living things will illustrate this. 



In one sense the happenings in a living cell are depend- 

 ent upon the chemical composition of the proteins, fats, 

 sugars and salts that are present, and upon the temperature, 

 the humidity, the illumination and other environmental fac- 

 tors. We cannot say that a given salt or a given proportion 

 of water " causes " one or another thing to happen. We 

 can say with some assurance that the total happening is in 

 some profound way the outcome of the total situation, con- 

 sidered in purely physical and chemical terms. On the other 

 hand, it would be just as true to say that the behavior in 

 a given cell is dependent upon the nature or constitution of 

 the whole organism. The water and salts and fats and sugar in 

 the cell of a dog's muscle are identical, so far as the chemist 

 and physicist can find out, with water and salts and fat and 

 sugar in the cell of a human brain. Molecule for molecule 

 they would behave in exactly the same way in a test-tube. 

 In many respects they behave the same way in their respec- 

 tive natural surroundings. In other respects, however, we 

 have reason to feel sure, the conduct of these materials is 



