THE UPSHOT 
long years before at last his black-prowed galleys clove the 
wine-dark seas for home. The ethical structure of that day 
covered wives, but had not yet been extended to human 
chattels. During the three thousand years which have since 
elapsed, ethical criteria have been extended to many fields 
of conduct, with corresponding shrinkages in those judged 
by expediency only. 
The Ethical Sequence 
This extension of ethics, so far studied only by philosophers, 
is actually a process in ecological evolution. Its sequences 
may be described in ecological as well as in philosophical 
terms. An ethic, ecologically, is a limitation on freedom of 
action in the struggle for existence. An ethic, philosophically, 
is a differentiation of social from anti-social conduct. These 
are two definitions of one thing. The thing has its origin 
in the tendency of interdependent individuals or groups to 
evolve modes of co-operation. The ecologist calls these 
symbioses. Politics and economics are advanced symbioses 
in which the original free-for-all competition has been re- 
placed, in part, by co-operative mechanisms with an ethical 
content. 
The complexity of co-operative mechanisms has increased 
with population density, and with the efficiency of tools. It 
was simpler, for example, to define the anti-social uses of 
sticks and stones in the days of the mastodons than of bullets 
and billboards in the age of motors. 
The first ethics dealt with the relation between indi- 
viduals; the Mosaic Decalogue is an example. Later accre- 
tions dealt with the relation between the individual and 
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