DREARINESS and a numbing confusion are characteristic features of discussion by social scientists about theories in their fields, and this is particularly true of discussion about sociological theories. The situation may arise, in part, because many social scientists, while making use of several different types of theories, are unclear about the differences between the types. It is worthwhile, therefore, to distinguish some of the kinds of theories present in the work of social scientists, and to comment on a few of the issues raised by the examples we shall give of each kind. We can then concentrate our attention upon the type which most concerns us in our efforts to answer the question ‘Are there hypotheses in the social sciences which are anything more than mere empirical generalizations?’