matter of social interaction and social co-ordination; for the activity of each member of a family group is co-ordinated in very definite and regular ways with the activity of all the other members of his group. Just as every co-ordination in the individual that persists is termed a habit, so every co-ordination that persists in a social group may be termed a social habit. In those large groups which we term peoples there is, of course, no objection to calling these regular modes of social activity "folkways," as Professor Sumner does.

Of course, there are many other ways in which social coordinations express themselves objectively. As we have already repeatedly said, the whole matter of social organization is simply a matter of the types of social co-ordination that persist among the members of a given group, that is, all the forms or modes of association are simply different objective expressions of social co-ordination. All of the objective regularities and uniformities in society, may, therefore, be looked at as so many objective expressions of social co-ordination. A custom, for example, is but a social habit which has persisted long enough in a people to gain a certain prestige, while what we call institutions are but sanctioned forms of association, or of social co-ordination.

The analysis of the various types of social co-ordinations has, as yet, only just begun. It is evident, however, that the types of co-ordination between individuals are as complex as human nature itself, and that an analysis of society into its various types of social co-ordination would be practically equivalent to an analysis of social structure as a whole. All possible co-ordinations between individuals exist, and hence, an infinite variety in the forms of human association. The honor of beginning a serious study of the various types of social co-ordination, that is, of the forms of association, belongs to Professor Simmel, of the University of Berlin, but his analysis is very far from satisfying. What he has studied chiefly are the empty forms of association, that is, the forms themselves without definite content, such as equality, superiority, subordination, and the like. He omits, for example, such common forms of social co-ordination as are seen in the family such as husband and wife, parent and child. For a full

understanding, however, of the types of social co-ordination, we must consider not merely their empty form, but also their content. It is apparently an inexhaustible task to classify and arrange the various types of persistent interaction between individuals. The progress of sociology as a science is, however, not dependent upon any exhaustive enumeration or classification of the types of social interaction. Rather, sociology must show the way in which types of social co-ordination arise and are changed into other types and the significance of the principal types for the collective life of man.

But the subjective expressions of social co-ordination are of not less importance than the objective expressions in folkways, customs, institutions, and social organization. Those subjective expressions are to be found in the mental attitudes which the individuals of the group maintain toward each other. A group of individuals carrying on a common life-process through interstimulation and response, must maintain certain habitual psychical attitudes toward each other in order that they may respond quickly and effectively, each to the stimulus which the activity of the others affords. Hence, the significance of feelings, emotions, ideas, and beliefs in all forms of human social organization. Feelings, emotions, ideas, and beliefs are, on the one hand expressions of common life-activities, and on the other, they powerfully reinforce and direct those activities. The family group again illustrates the matter beautifully. The mental attitude of the members of a family toward one another is an expression of their common group life and group activities. Corresponding to their habitual modes of interaction, are certain feelings, or emotional attitudes, and even certain ideas and beliefs. Thus, the social co-ordinations of husband and wife, parent and child, are each subjectively expressed by appropriate feeling, or emotional attitudes.

Inasmuch as the family group is organized largely on an instinctive basis, the subjective expressions of its co-ordinations

Professor Cooley in his Social Organization and Professor Ross in his Foundations of Sociology seem to me to have begun a much more fruitful analysis of the forms of association.

are chiefly in feeling and emotional attitudes. Hence, we ordinarily think of such relationships as husband and wife, parent and child, in terms of feeling. In larger social groups, however, built up chiefly upon the basis of acquired habits, common ideas and beliefs may be the chief expression of social co-ordination; but in any case, habitual modes of interaction must come to have attached to them certain feeling tones in the individuals concerned —that is, they must give rise to certain feeling attitudes of certain individuals toward each other. In animal groups, where the interactions are almost wholly instinctive, not much more than the feeling attitude may exist as the subjective accompaniment of social co-ordination, but in human societies, with their larger element of acquired habit, the chief subjective expressions of social co-ordination are frequently common ideas and beliefs; thus, in a modern nation, unity of action and of life is secured partly through sentiments like patriotism, but even more through certain generally accepted ideas and beliefs. Such generally accepted ideas and beliefs, which form the psychical basis of institutions, may be called "co-ordinating ideas." The importance of such co-ordinating ideas in human social and institutional life, although first emphasized by Comte, has not as yet been adequately investigated by sociologists.

The whole matter of uniformities of feeling, belief, and opinion in social groups evidently, then, must be studied in connection with social co-ordinations if it is to be understood; for the mental attitudes of individuals toward each other and toward their group as a whole are expressions of the way in which they are socially co-ordinated. These subjective expressions of social coordination are, of course, also marks of incipient stages of new forms of social organization as well as of existing forms; for it is manifest that in a group of individuals carrying on a common life-process through interstimulation and response, mental attitudes mark the beginning of new co-ordinations, or common activities, as well as those co-ordinations that have become fixed as social habits.

Thus far in this discussion, our point of view has been that of the social habit, and it may be well to note a little more fully

the nature of social habits. As has already been said, social habits are simply social co-ordinations that persist. In their various modifications they are known, in the larger human groups, as folkways, customs, manners, morals, laws, institutions, and the like. In brief, all the tangible uniformities of the social life are social habits. It is evident that they rest partly on instincts, partly on acquired habits. As has already been noted, in all social species, the instincts of individuals are made so that they fit into each other, as it were, and provide certain social co-ordinations to start with. This is especially true of man-human family life, as we have just seen, illustrating these instinctive co-ordinations between individuals. Hence, the instinctive origin of human society-a doctrine now generally accepted by psychologists and sociologists alike. But it is also true that in man these social habits are largely acquired. While the original or instinctive coordinations between human individuals may be numerous, yet on account of the complexity of man's social life, these original social co-ordinations have become overlaid with a vast mass of acquired social habits that are even more important for the distinctive character of human society than the instinctive co-ordinations. Hence the need in human society of definite forms of mental interaction, or interstimulation and response, whereby every individual may acquire the habits of his group. Hence also why human groups have developed such definite forms of interstimulation and response, as oral and written language, and superior types of suggestion and imitation.

But we must now leave the point of view of social habit, and ask what happens when social habits change, for we know that in social groups, as in individuals, habitual ways of action are continually being modified. The social co-ordination that exists today in a group of individuals may no longer exist tomorrow. Even the type of co-ordination itself changes. Now, in a group of individuals carrying on a common life-process by interstimulation and response, there must be some very definite mechanism by which habitual ways of interaction are modified or even radically changed. That mechanism is found in the various forms of communication and in other simpler forms of interstimulation,

such as suggestion. Psychologists, as a rule, have had little to say about communication, probably because it is so obviously a social process. At any rate, all that we know goes to show that communication is a device to carry on a common life-process among several distinct, though psychically interacting, individual units. All the higher forms of communication had their origin in the needs of, and exist for the sake of perfecting, a common life. Indeed, it may be well argued that the distinctive mark which separates human society from animal groups and which makes it, to some extent, separate and unique, is the possession of language, or articulate speech. In the transition from one social habit to another, in the breaking-down of one social co-ordination and in the building-up of another, then, various forms of communication come in to mediate the process. Just as in the individual the transition from one habit to another is marked by processes of discrimination, so in the social group the transition from one social habit to another is marked by processes of criticism and discussion. When anything goes wrong with the working of a social habit, various appreciations of the social situation are communicated from one individual to another. Public criticism marks, then, the bad working or the breaking-down of some social coordination. Discussion of the whole social situation comes in to pick out the elements in the old habit that are unworkable and to select those that may be made the basis of a new habit. Discussion works in society, therefore, very largely as the association of ideas works in the individual mind. Through discussion certain elements in the situation, objective stimuli, or ideas, are selected and fixed upon by the group for the building-up of a new coordination. When the ideas for the building-up of the new co-ordination have become relatively settled we have what is called the formation of a public opinion. In order to carry out this public opinion there is usually necessary the selection of certain individuals that are judged to be especially fitted to carry out the new social policy and we have the phenomena of leadership, and of authority resulting. Along with these more tangible processes of intercommunication, there are, of course, those less tangible processes of interstimulation, such as various forms of