6oo THE AMERICAN JOURNAL OF SOCIOLOGY
gist, then, has to interpret the forms of the regular co-ordinated actions between individuals, and the changes which take place in them, from the standpoint of a collective life-process.
The biological origin of social co-ordinations need not concern the psychological sociologist as such.^ It is sufficient for him to note that the instincts of all individuals of a social species are made so that they fit into one another, so to speak ; so that their instinctive reactions are co-ordinated with one another. In the social groups of man, moreover, these instinctive reactions are modified so through habit that the adjustment of the activities of individuals to each other reaches such a high degree of perfec- tion that groups often act with the spontaneity and certainty of individual units. Through instinct and habit, then, wrought out under social conditions, the activities of individuals become socially co-ordinated ; and practically the psychological sociologist has to start his interpretation of the social life with these social co-ordinations. Just as the psychologist cannot get back of organic activity and have anything left of mental life, so the sociologist cannot get back of social activity and have anything left of social life, for we do not think of the group as a unity except in connection with its activities. The social co-ordination is the sign of social relationships, social organization, social life, throughout the animal scale. Individuals living together in mere proximity cannot be said to have social relationships until they become functionally related to each other as parts of some func- tioning whole. In a psychological interpretation of society, there- fore, we must begin with concerted or co-ordinated activity, with the group acting together in some particular way, for it is this which constitutes the group a functional unity, and which is the first psychic manifestation of group life.
It may be objected that what we have called the social co- ordination is nothing more than social co-operation under another name. But social co-ordination, as already implied, does not necessarily mean that the relationship is one of mutual aid It may be one of exploitation, or even of modified hostility. There
■See my article on "The Origin of Society" in the American Journal of Sociology for November, 1909.
