uenced by his
natural surroundings. It is the policy of nature to allow an
unlimited number of individuals to be born, while at the same time the
amount of food and space upon the earth is limited. This results in a
perpetual struggle for survival, or existence. In this struggle,
through the process of natural selection, the individuals possessing
those qualities suitable for life in their environment are allowed to
survive and to transmit these favorable qualities to their offspring,
whereas those having the less fit traits are weeded out. In a word,
the battle is to the strong, the race is to the swift.[3] The chances
of survival of all organisms, therefore, depend on adaptation or
adjustment to external conditions.[4]

Besides adaptation, however, nature also presents to the plant or
animal other alternatives whenever any fundamental change occurs in
the environment which affects the life of these individuals. These
alternatives are death, degeneration, and flight. These have all had
their effects upon man as well as upon plants and animals. "It is well
known that men die when natural conditions become favorable enough;
famines recurrently sweep many from the earth. Again, they degenerate
when they are forced to live a life that it is possible to live but
only in a miserable way. Some of the lowest tribes of men, like the
South African Bushmen, or the Digger Indians, have been forced by
stronger tribes to withdraw into the desert and to exist upon a lower
plane of life. The physique of such peoples betrays the hardships
which they have suffered. Men also flee from an unfavorable
environment, thus escaping death or degeneracy, if the way into a more
favorable locality lies open to them. Much of migration and
colonization comes under this alternative."[5] This topic is well
illustrated by those farms of New England which have been abandoned
by their former owners, and have been occupied by immigrants from
Europe.[6]

As man is compelled to adapt himself to his natural surroundings in
order to survive, so he must do in regard to his human or social
environment. This external situation is due to the fact that man lives
his life in a group, or a society, composed of numerous individuals
like himself. In this society are laws or conventions which are
imposed on all by the group, and which all are required to obey.[7]
Often, however, it happens that in various ways the acts of large
numbers of the group come into conflic