Delusion occupies a pivotal position across the depth-psychology corpus, serving simultaneously as a clinical symptom, a structural feature of disordered reality-contact, a spiritual category, and — most ambitiously — a condition endemic to ordinary human consciousness. Bleuler’s foundational psychiatric treatment in *Dementia Praecox* establishes delusion as neither a secondary product of hallucination nor a simple hypertrophy of the ego, but as an expression of the same primary distortion of reality that pervades all schizophrenic symptomatology; it is coordinate with, not caused by, sensory deception. Freud’s Introductory Lectures press the question further, demanding that hereditary predisposition alone cannot account for the specific content of delusional jealousy and pointing toward wish-fulfillment as the generative force. McGilchrist relocates the mechanism neurologically, arguing that extravagant delusions are predominantly products of right-hemisphere damage or dysfunction — distorted reality-judgments, as opposed to the distorted perceptions of hallucination. The Philokalia tradition reads delusion as a spiritual-ontological catastrophe rooted in arrogance and self-conceit, producing a cascade from illusory vision through blasphemy to mental derangement. Buddhist and Zen voices — Brazier, Campbell, the Taoist tradition in Wilhelm — extend the category to name ordinary self-identification as the foundational delusion, the root obscuration from which greed, pride, and opinionatedness ramify. Campbell pointedly distinguishes the therapeutic aim of returning the patient to ‘the general delusion’ from the religious aim of extinguishing delusion altogether. These positions together reveal a productive tension: whether delusion is a pathological exception to normal cognition, or whether normal cognition is itself a structured delusion that clinical and contemplative disciplines must both, in their different registers, dissolve.