450 Life and [mmortalty. 
the intellectual faculties would have been aided and modified 
in an important manner, for if one man in a tribe, more saga- 
cious than his fellows, had invented a new snare or a 
weapon, or other means of attack or defence, the plainest 
self-interest, with no great help of reasoning power, would 
have prompted the other members to have imitated him, 
and thus all would have been profited. Habitual practice of 
each new art must likewise in some slight degree strengthen 
the intellect. If the new invention were an important one, 
the tribe would increase in numbers, spread and supplant 
other tribes, and thus rendered stronger numerically there 
would be a better chance of the birth of other superior and 
inventive members. Should these last be so fortunate as to 
leave children to inherit their mental superiority, the chance 
of the birth of still more ingenious members would be some- 
what better, and in a very small tribe would be decidedly 
better. 
That primeval man, or his ape-like progenitors, should 
have become social, they must have acquired the same 
instinctive feelings which impel other animals to live in a 
body, and they doubtless exhibited the same general disposi- 
tion. When separated from their companions, for whom 
they would have felt some degree of love, they would have 
experienced a feeling of uneasiness. They would have 
warned each other of danger, and have given mutual aid in 
attack or defence. All this implies some degree of sym- 
pathy, fidelity and courage. Such social qualities, whose 
paramount importance to the lower animals is undisputed, 
were doubtless acquired by the progenitors of men in a simi- 
lar manner, namely, through Natural Selection, aided by 
inherited habit. In the never-ceasing wars of savages, 
fidelity and courage are all-important, and certainly when 
two tribes of primeval man, living in the same country, came 
into competition, the one that contained the greatest number 
of courageous, sympathetic and faithful members, who were 
ever ready to warn each other of danger, and to assist and 
