THE GROWTH OF GROUPS 181 



conventionally into these classes according to the amount 

 of their possessions. The sociologist observes that the 

 lower class, in some parts of the world, is increasing 

 owing to their higher birth rate, while at the same time 

 the middle class is diminishing. He also observes that 

 the middle class is fitter than the lower class. Since he 

 is able to observe the greater fitness of the dwindling 

 class, it is evident that in his eyes fitness is an attribute 

 apart from success and failure, that may be a concomitant 

 of one or the other. 



This argument is used here merely for an illustration. 

 I do not believe for an instant that any essential human 

 attribute is more common in the middle class than in 

 any other class. There are different types and degrees 

 of mental qualities, but they are to be seen in every 

 section of society. It seems that the essential human 

 qualities are not altered by nutrition or education, 

 although they are various and changing. 



Man has long observed success and failure and tried 

 to explain them. Darwin taught that organisms succeed 

 because of their fitness. But in substituting the word 

 fitness for the older formula, he did not elucidate any thing, 

 unless it can be shown that fitness is an attribute in its 

 own right. 



The term fitness is used at present to express at least 

 three separate ideas. 



1. To express the adaptation of organisms, that is 

 to say, a certain similarity between living things and 

 those works of man that are adapted to a purpose. 



2. To express an idea that springs from the egoistic 

 side of the human mind, an idea that is in each mind in 

 regard to itself and is present even in those classed as 



N 2 



