Morals is the paradigmatic area for which the case for Durkheim's account of the reality of social facts is articulated (Giddens, 1971, p. 218). The thrust of Durkheim's argument is that obligation cannot be understood without some notion of causally compelling social facts. This is a puzzling argument, in part because of its structure. As we have seen, the Rules begins with a definition of social facts that defines these facts in terms of "generality", and identifies generality with the possession of an obligatory character — this last left only vaguely specified (1964, p. 9; 1982, p. 56; 1937, p. 10). By the point in the text that it is claimed that 'social facts' are necessary to explain obligation (e.g., 1964, pp. 121–24; 1982, pp. 142–44; 1937, pp. 120–23), a great many things other than obligations have been included in the category, and the argument begins to seem to be little more than a tautology, whose tautologous structure is concealed by the strange variousness of the things that fall into the category of social facts, a diversity that many commentators have complained about (e.g. Giddens, 1971, p. 218; Lukes, 1971, pp. 190–93).