EVOLUTION MADE PLAIN 49 
causing idiocy, stupidity, insanity and crime, 
are a hundred times more frequent in man than 
in lower animals, wild or domesticated. Why 
this difference? The answer is easy for any¬ 
one familiar with the laws of evolution. 
The sedulous sifting by natural selection of 
animals in the wild state has left no sickly or 
half-witted degenerates to burden the world 
with a like progeny. If at rare intervals the 
law of variation should drop a mal-formed spec¬ 
imen into Nature’s sieve it would be quickly 
eliminated along with the great mass of aver¬ 
ages. Practically the same is true of domesti¬ 
cated animals where the watchful eye of man 
is substituted for Nature’s. 
As natural selection is hampered in its oper¬ 
ation among domesticated animals by the inter¬ 
ference cf man, so is it limited on the human 
plane. There, we find virtually no selection, 
neither natural nor artificial. Hence the de¬ 
generacy—physical, mental, moral. Both Na¬ 
ture and man, in their respective fields of 
operation, select only a few of the best for prop¬ 
agating purposes — Nature eliminating the 
rest by death, and man by sterilization. But 
on the human plane man—acting mercifully 
toward the individual, mercilessly toward the 
race—does his best to thwart Nature. He pro¬ 
longs the lives of weaklings, of the maimed- 
from-birth, cf the deaf and dumb and blind, 
and of the mentally sub-normal. So far, all is 
well. But he permits these victims of an in¬ 
ferior ancestry to marry and procreate almost 
without limit. What then can we expect but 
for the world to be burdened with invalids, 
