734 THE AMERICAN JOURNAL OF SOCIOLOGY
which new qualities, and conditions, and arrangements of the parts may be derived. There are rather relations and activities of the elements on the ground of which alone unity maybe pred- icated." In this sense it may be said that society is only a name fora function. The function is reciprocal influence, which, to be sure, may be more or less close, so that, according to Simmel, there is " more and -less" of society.
In opposition to Staummler also, has Simmel rightly empha- sized the importance of this reciprocity. Staummler defines society as " an externally regulated coexistence of human beings" (loc. cit., p. 90). Simmel on the contrary contends that external regulation is only a secondary sine qua non derived from reciprocity, without which the regulation could not come into being.
It may be replied to Tonnies further that reciprocal influence must exist in order that an exchange may take place. Exchange is, as even Tonnies psychologically interprets it, " a resultant of two divergent components." In order that a resultant may arise, it is a mechanical necessity that the components shall have an effect not alone on a common point of contact but upon each other. In our case, volitions, psychical forces, are the compo- nents. Accordingly in every case of exchange there is con- cerned in fact a more or less intensive psychical reciprocity between the parties. The "root" of society, therefore, is not the derived exchange, but the reciprocity which is the foundation and source of all intercourse.
From the standpoint of reciprocity Simmel undertakes to elucidate the relation of the individual to the group and of groups to each other. The question is essentially as to the rela- tion between differentiation and socialization. The well-known dictum of Spencer that differentiation and integration are in direct proportion to each other, finds here complete justification and splendid illumination. So profound and comprehensive, and yet so compact is the treatment, that it is impossible to ren- der a brief account of the argument. One or two points of view, which seem to me fundamental, may be indicated.
