Nature of the UNm:RSE 21 



like structures that operate to bring about such 

 regulatory results : tubes for carrying nutrient fluids, 

 cords for conveying impulses from one part of the 

 body to another, and a thousand other such arrange- 

 ments. 



Many of these structures are such as to bring 

 about a correspondence between things that occur 

 inside the body of the organism, and those that take 

 place outside in the surrounding world. The living 

 thing develops the power to move away from condi- 

 tions that affect unfavorably its inner life processes 

 and to seek and hold conditions that are favorable. It 

 develops external and internal structures that regis- 

 ter the events that occur : the external events that act 

 on it, and the reactions that these induce in the or- 

 ganism itself. It develops sense organs, eyes, and ears 

 that register the outer events ; nerves, brain, and 

 other parts that mediate between the external and 

 the internal events and that register the organism's 

 responses to the outer events. Its internal constitu- 

 tion thus comes to depend on the environmental con- 

 ditions to which the organism has been subjected and 

 on the responses that it has given to those conditions. 

 In consequence, its present activity comes to be domi- 

 nated in large measure by past conditions and past 

 reactions. There is a tendency in the universe toward 

 uniformity in the sequence of conditions and results ; 

 given conditions now tend to produce the same results 

 that they produced at an earlier occurrence. Through 

 this tendency toward uniformity in the outer world, 

 it becomes possible for the organism to become pre- 



