Mary Douglas b. 1921–d. 2007 was an anthropologist and social theorist working in the Durkheimian tradition. Most anthropologists know her 1966 book Purity and Danger (Douglas 1966, cited under Social Organization in Microcosm), and perhaps Natural Symbols (Douglas 1970, cited under Variation in Elementary Forms of Institutions and Social Organization). In other disciplines her The World of Goods (Douglas and Isherwood 1979, cited under Explanation, Institutionalization, and Ritual) and How Institutions Think (Douglas 1986, cited under Explanation, Institutionalization, and Ritual), Risk and Blame (Douglas 1992, cited under Variation in Elementary Forms of Institutions and Social Organization), Leviticus as Literature (Douglas 1999a, cited under Social Organization in Microcosm) and Thinking in Circles (Douglas 2007, cited under Late Ethnographic Work) have been very influential. She argued that institutional social organization exhibits only limited variation in its elementary forms, although in empirical settings, many hybrids of these forms are available. These institutional forms of social organization and disorganization shape and therefore causally explain “thought styles,” meaning the manners in which people classify, remember, forget, feel, and so on. The causal mechanism by which organization cultivates thought style, she argued, works through quotidian ritual, even for those who reject grand public ceremonial: “As a social animal, man is a ritual animal” (Douglas 1966, cited under Social Organization in Microcosm, p. 63). Douglas cross-tabulated Durkheim’s two dimensions of institutional variation in social organization (from Durkheim’s book Suicide)—social regulation and social integration, or, as she called them, “grid” and “group.” These forms specify organization and thought style in any setting, irrespective of technological sophistication or field of endeavor. In Suicide, Durkheim attended to the apices of the dimensions; Douglas concentrated on forms derived deductively in the resulting four cells. These forms are hierarchy (strong regulation and integration), individualism (weak regulation and integration), enclave (weak regulation, strong integration), and isolate ordering (strong regulation, weak integration). Contrary to the conventional wisdom that there is a “micro-macro problem,” Douglas argued that the same elementary forms organize people at the large and small scales alike. Methodologically, she argued that research should identify things that are anomalous within the prevailing classifications, examine how those anomalies are dealt with (or not), and seek to explain them functionally. She examined empirical anomalies about animals, dirt (for which she revived Lord Chesterfield’s definition of “matter out of place”), risks, and dangers. In her last years, she applied her method to ancient Israel as revealed in the Hebrew Bible, showing how distinct styles of composition are cultivated among authors and editors from different institutional settings. Her theory is a fully specified rival both to postmodernist rejections of causal explanation and to narrower rational choice conceptions of explanation by reference to interests and a single thought style. Other researchers extended her theory by supplying theories of change, dynamics, disorganization, hybridity, and settlement among elementary forms.