Taboo occupies a pivotal position in the depth-psychology corpus, functioning simultaneously as an ethnographic datum, a structural analogue to neurotic prohibition, and a window onto the ambivalent architecture of the unconscious. Freud’s *Totem and Taboo* (1913) remains the foundational treatment: drawing on Wundt, Frazer, and the *Encyclopaedia Britannica*, Freud reads taboo not as arbitrary primitive superstition but as the oldest stratum of unwritten law, distinguished by its inherent ambivalence — the word itself, he argues, encodes both the sacred and the unclean, the desired and the forbidden. The persistence of any taboo is, for Freud, evidence that the underlying desire survives; prohibition and longing are inseparable. He maps taboo systematically onto obsessional neurosis: both involve externally imposed primeval prohibitions, both breed atonement ceremonies, both propagate by contagion. The Jungian tradition, through Samuels and Stein, displaces the emphasis from repression to differentiation: the incest taboo, on this reading, is not merely a barrier against desire but a generative psychological distance that stimulates consciousness, sanctifies parental figures, and inaugurates genuine interpersonal love. Edinger extends the analysis theologically, tracing the Hebrew concept of sin to taboo psychology, where the tabooed object carries suprapersonal energies dangerous to ego inflation. Across all these positions, taboo marks the boundary between the ego’s domain and the numinous excess that surrounds it.