PROLEGOMENA TO SOCIAL PSYCHOLOGY 66 1
individual psychology for new and deeper interpretations of the economic life. They have done so with some degree of success, both because individual psychology is a factor in all social inter- pretation, and because of its essential unity with social psy- chology. Where they have failed, they have failed chiefly because they have lacked a social psychology to complete their view. Take, for instance, the problem of value. The Austrian economists were successful in explaining the phenomenon of economic value in so far as they referred it to a psychological origin ; they were unsuccessful in explaining it in so far as they referred it to a purely individual origin. Economic value is now widely admitted to be a social phenomenon, to be explained only through reference to the social life as a whole, or, at least, to the life of the particular group within which it appears. The last word upon value is, however, far from said, and social psychology may yet throw much light upon this fundamental economic problem. The theory of consumption furnishes another illustration. So long as there was no subjective interpretation of the economic life, consumption occupied no place in the dis- cussions of economic writers. Now, however, the theory of consumption is admitted to be one of the most important parts of economic science, though a satisfactory theory remains yet to be developed. As Professor Patten has pointed out, such a theory can be developed only along socio-psychological lines, since consumption is a matter of social (group) habits, cus- toms, and feelings. It must, in other words, be worked out with the aid of social psychology. In the closely related ques- tion of economic crises the necessity of understanding the social psychical processes is even more plainly evident. Hitherto economic science has had almost no serious theory of crises. What has been written concerning them has often been worth- less, and often, it is not too much to say, vague, mysterious, and superstitious. To the social psychologist, however, it is evident that economic crises are phenomena that lie wholly within the psychical process of group-life, and that their explana- tion is to be found in the mechanism of that process. A satis- factory theory of economic crises, if such can ever be given,
