Totem and Taboo, published by Sigmund Freud in 1913, applies psychoanalytic theory to questions about the origins of religion, morality and social organization, drawing comparisons between practices Freud read about in anthropological accounts of what were then called primitive societies and patterns he observed in the neurotic and obsessional behavior of his psychoanalytic patients. Freud argues that totemism, the symbolic association of a clan with a particular animal treated as both sacred and, under most circumstances, forbidden to kill or eat, and taboo, systems of prohibition surrounding sacred or dangerous objects and actions, share a common psychological root with the compulsive rituals and ambivalent attachments he observed clinically.
The book's most provocative and lasting claim is a speculative origin story Freud proposes for religion and social order together: a primal horde in which sons, resentful of a dominant father who monopolized the group's women, band together to kill and consume him, then experience overwhelming guilt that leads them to institute the very prohibitions, against violence within the group and against sexual access to the women the father had claimed, that Freud argues underlie totemic religion and the incest taboo more broadly.