CHAPTER V 



THE WORLD OF LIVING ORGANISMS 



Now that in a general way we have become clear as to the 

 properties of living organisms, it must be our task to in- 

 vestigate the way in which these properties work. 



Every animal is a subject, which, in virtue of the structure 

 peculiar to it, selects stimuli from the general influences of 

 the outer world, and to these it responds in a certain way. 

 These responses, in their turn, consist of certain effects on the 

 outer world, and these again influence the stimuli. In this 

 way there arises a self-contained periodic cycle, which we 

 may call the function-circle of the animal. 



The function-circles of the various animals connect up 

 with one another in the most various ways, and together form 

 the function-world of living organisms, within which plants 

 are included. For each individual animal, however, its 

 function-circles constitute a world by themselves, within 

 which it leads its existence in complete isolation. 



Let us now proceed to analyse this function-world into 

 its parts. The sum of the stimuli affecting an animal forms 

 a world in itself. The stimuli, considered in connection with 

 the function-circle as a whole, form certain indications, 

 which enable the animal to guide its movements, much as 

 the signs at sea enable the sailor to steer his ship. I call 

 the sum of the indications the world-as-sensed. 



The animal itself, by the very fact of exercising such 

 direction, creates a world for itself, which I shall call the 

 inner world. 



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