lysis social solidarity is based on sentiment and habit.
It is the sentiment of loyalty and the habit of what Sumner calls
"concurrent action" that gives substance and insures unity to the state
as to every other type of social group. This sentiment of loyalty has
its basis in a _modus vivendi_, a working relation and mutual
understanding of the members of the group. Social institutions are not
founded in similarities any more than they are founded in differences,
but in relations, and in the mutual interdependence of parts. When these
relations have the sanction of custom and are fixed in individual habit,
so that the activities of the group are running smoothly, personal
attitudes and sentiments, which are the only forms in which individual
minds collide and clash with one another, easily accommodate themselves
to the existing situation.

It may, perhaps, be said that loyalty itself is a form of
like-mindedness or that it is dependent in some way upon the
like-mindedness of the individuals whom it binds together. This,
however, cannot be true, for there is no greater loyalty than that which
binds the dog to his master, and this is a sentiment which that faithful
animal usually extends to other members of the household to which he
belongs. A dog without a master is a dangerous animal, but the dog that
has been domesticated is a member of society. He is not, of course, a
citizen, although he is not entirely without rights. But he has got into
some sort of practical working relations with the group to which he
belongs.

It is this practical working arrangement, into which individuals with
widely different mental capacities enter as co-ordinate parts, that
gives the corporate character to social groups and insures their
solidarity. It is the process of assimilation by which groups of
individuals, originally indifferent or perhaps hostile, achieve this
corporate character, rather than the process by which they acquire a
formal like-mindedness, with which this paper is mainly concerned.

The difficulty with the conception of assimilation which one ordinarily
meets in discussions of the race problem is that it is based on
observations confined to individualistic groups where the characteristic
relations are indirect and secondary. It takes no account of the kind of
assimilation that takes place in primary groups where relations are
direct and personal--in the tribe, for example, and in the family.

Thus Charles Francis A