The term ‘lie’ in the depth-psychology corpus is not reducible to a simple moral category; it ramifies across ontology, psychology, social theory, and spiritual diagnosis. Plato, the locus classicus for this discourse, draws the decisive distinction between the ‘true lie’ — the deception of the soul itself, the deepest falsification of its relation to reality — and the ‘lie in words,’ which can serve expedient or even beneficent ends. This ontological hierarchy, in which self-deception is the gravest form of falsehood, resonates throughout the corpus. In Nietzsche, the lie operates as social critique: the Victorian era, as Jung remarks in his Zarathustra seminars, erected a ‘mountain of lies’ underpinning the will-to-power beneath sentimental idealism; Nietzsche’s Zarathustra confronts the ‘liar from the heart’ with violent lucidity. In clinical and biblical-psychological registers (Shaw), lying is understood as a compulsive, self-reinforcing symptom of addiction — a seared conscience that ultimately deceives the self. Pascal registers the paradox of those who ‘lie simply for the sake of lying,’ untethered even from interest. McGilchrist, citing Patmore, counters all these with the assertion that truth is not a human invention and that ‘the lie shall rot.’ The oath-lie linkage, explored by Benveniste and the ancient Greek sources, grounds the social prohibition against lying in communal trust and the sacred. The term thus sits at the intersection of self-knowledge, social contract, spiritual integrity, and the critique of modernity.