There are those who believe that mutual aid has been a more dynamic factor in the development of terrestrial life than competition. Cooperation has been an important element in the evolution of animal life, and it has operated among nearly all animals, from the humblest to the highest. Far down near the beginning of organic existence we find the one-celled forms huddling together in colonies, giving rise in the course of time to the many-celled animals. But to conclude that cooperation is the chief factor in animal development is to shut one’s eyes to one of the most obvious and overwhelming facts of organic evolution. Individualism antedates mutualism, both among the one-celled forms and among the many-celled metazoa. Cooperation everywhere is the sequence of a long preliminary of individual contention. And cooperation does not mean cessation of struggle, either among those co-operating or among the groups themselves, as Kropotkin and other exaggerators of the mutual aid factor seem to assume. It usually does little more than transfer the struggle from individuals to groups. When a lot of pelicans or wolves get together and work together in order that they may thereby the better defend themselves or slay others it is hard to see how such facts can be placed to the credit of cooperation any more than to that of competition. Then, too, excepting in a few societies of insects, cooperation has not gone so far as to do more than slightly alleviate the competition even among the members of a co-operating group. Competition is a much more common and influential fact in the phenomena of life than cooperation, for it involves a large part of the activity of individual life, and is also prominent in all social activities.