SOCIAL DIFFERENTIATION 193 
combinations of others, and he even differentiates himself 
from and opposes those with whom he combines for other 
purposes. 
This latter combination finds its most characteristic 
expression in the merchant class. The merchant combines 
with other merchants in an association for common inter- 
ests like commercial legislation, class prestige, and the 
maintenance of prices. These common interests unite the 
class as a whole in its relations with outsiders. But, on the 
other hand, the merchant is in competition with and there- 
by in opposition to his fellow-merchants. Membership in 
that social circle means at the same time a co-operation 
with others and a competition against others. It means a 
position similar to that of others and at the same time a 
position apart from others. The individual guards his own 
interest by waging a severe competition against those with 
whom he is strongly united for the purpose of safeguarding 
their common interests. This internal opposition is most 
clearly expressed in the merchant class, but it is present in 
nearly all associations. Even the ephemeral polite society 
that gathers for an evening function is not free from it. 
Human nature seems to show a fundamental need for 
both types of association, a fundamental desire for both 
co-operation and competition. The individual wants to 
feel and to act with others, but he also wants to act against 
others. A certain proportion between the two is apparently 
a necessity for the full expression of his individuality. He 
can satisfy that desire by a participation in associations 
which have these formal characteristics quite irrespective 
of what their content is. In many cases the participation 
in certain associations is due, not to their factual signifi- 
cance, but to the fact that they give the individual a cer- 
tain proportion between competition and co-operation in 
his associative life. It is often due to this fact that the in-