Genetic Progress by Voluntarily Conducted Germinal Choice 
have resulted in some selection in the direction of making such 
behaviour tolerable and not entirely hypocritical. At the same 
time, even in the great civilizations of ancient and mediaeval 
times charity began at home and there must have remained a 
severe struggle for existence in which those genetic lines pros- 
pered more whose genes were so constituted as more effectively 
to serve ‘““number one’’, and “‘number one junior’, and the 
others in the little family conspiracy. 
It might at first sight be surmised that natural selection was 
inevitably reduced under the circumstances of civilization. 
However, in both barbaric and civilized societies of the past 
the size of the population tended to rise in step with its increase 
in productive capacity. It followed that the ordinary individual 
and his family remained about as close as ever to the economic 
level where their survival was in jeopardy. Under these circum- 
stances, whether or not they tended to die out or to multiply, 
relatively to the rest, depended for the most part on the efforts 
of that same person or family (despite some notable exceptions 
to this rule, as in the Inca empire and among Pueblos). Conse- 
quently, natural selection must have continued within civilized 
populations to enhance whatever social traits led people pri- 
marily and actively to serve their own family, and, secondarily, 
to get along with their other associates to a degree sufficient for 
eliciting the latters’ good will. At the same time, however, as 
previously explained, there could no longer be as high a genetic 
premium on service to the whole community as when the com- 
munities were smaller, more numerous, and subject to more 
genetic isolation from one another. 
THE NEGATIVE FEEDBACK ESTABLISHED BY MODERN CULTURE 
Modern technologies and social organization, working in 
combination, have altered the manner of operation of selection 
much more drastically than this in those typical industrial 
societies in which the increase in the means of subsistence has 
been greater than the increase in the size of population. Not 
only is there in these societies an ever more rapid disappearance 
of that genetic isolation between small groups which underlies 
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