40 THE AMERICAN JOURNAL OF SOCIOLOGY
sociological formation which is methodologically simplest is that between two elements. It furnishes the scheme, the germ, and the material for countless more complex formations ; although its sociological significance by no means rests merely upon its extensions and its multiplications. It is rather itself a socializa- tion, in which not only many forms of socialization realize themselves, purely and characteristically, but the limitation to a duality of the elements is, indeed, the condition under which alone a certain series of forms of relationship can emerge. The typically sociological nature of the same appears then not only in the fact that the greatest manifoldness of the individualities and of the combining motives does not alter the similarity of these formations, but rather that these sometimes occur quite as typically between pairs of groups families, states, combina- tions of various sorts as between pairs of single persons.
The peculiar conferring of characteristics upon a relationship through the duality of persons concerned in it is exhibited by everyday experiences. For instance, how differently a common lot, an undertaking, an agreement, a shared secret binds each of two sharers, from the case when even only three participate. The specific character of this difference is determined by the fact that the relationship, as a unity composed of its individuals, as a special structure beyond these, has a different bearing upon each of its participants from that of a more complicated struc- ture to each of its members. However it may appear to third parties as an independent, superindividual unity, yet, as a rule, that is not the case for its participants, but each regards himself in antithesis only with the other, but not with a collectivity extending beyond him. The social structure rests immediately upon the one and the other. The departure of each single indi- vidual would destroy the whole, so that it does not come to such a superpersonal life of the whole that the individual feels him- self independent ; whereas, even in the case of an association of only three, if one individual departs, a group may still con- tinue to exist.
There are, nevertheless, exceptions to this character of the dual groupings, the most decisive of which seems to appear in
