6o6 THE AMERICAN JOURNAL OF SOCIOLOGY
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 tran- sition from one habit to another is marked by processes of dis- crimination, so in the social group the transition from one social habit to another is marked by processes of criticism and discus- sion. When anything goes wrong with the working of a social habit, various appreciations of the social situation are communi- cated from one individual to another. Public criticism marks, then, the bad working or the breaking-down of some social co- ordination. 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. Discus- sion 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 co- ordination. 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 leader- ship, 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
