346 The American Naturalist. [April, 
of claws and teeth for victory, but brought his mental resources 
into play. Cunning, caution, boldness where necessary, close 
observation, variation in modes of attack and defence to suit 
varying circumstances, are hostile methods of purely mental 
origin. They are not peculiar to man; many of the lower 
animals employ them, though none to such an-extent as man. 
But the use of other than the natural weapons is nearly peculiar 
to man. Some of the monkeys occasionally and imperfectly 
employ missiles, but man alone has become aware of their great 
utility, and employs them constantly and skilfully. By the use 
of artificial implements of warfare his powers were enormously 
increased, and the steps of progress in his subordination of the 
lower animals were doubtless marked out by his invention of 
more and more efficient weapons. 
We take it for granted that the animal world did not submit 
without a struggle, and a protracted one. Step by step, through 
many centuries of conflict, were the larger animals subdued. It 
was man’s mind, not his body, that subdued them. Physically 
they were his equals or superiors. His superiority lay in his 
mental resources, and his victory was due solely to his mental 
superiority. The effect of the conflict, therefore, bore principally 
upon his mind, and its organ, the brain, very little upon the 
body; and when we consider the extent of the achievement we 
cannot be surprised at the result. Such an advantage, if gained 
_ by any of the lower animals through variation of physical struc- 
ture alone, could not but have produced radical and extraordinary 
changes in size, strength, and utility of natural weapons. In man 
the influences of variation were exerted upon the brain alone, 
and the decided increase in size and activity of this organ does 
not seem too great for the magnitude of the result. The conflict 
ended, man settled down to quiet consciousness of victory, but 
with a much larger brain, and greatly superior mental powers 
than at the beginning of the struggle. This brain and the higher 
mentality it indicated enabled him to hold the position he had 
gained, but there was no special further strain upon his powers, 
and he simply held his own until a new era of war, now between 
man and man, or between man and cold and stubborn nature, 
* 
