Moonlight in the depth-psychology corpus is not merely a meteorological or poetic phenomenon but a charged symbolic medium through which the unconscious communicates its most ambivalent messages. Across the major voices — Jung, von Franz, Edinger, Greene, Nichols, and their interlocutors — moonlight functions as the luminous atmosphere of an inherently double-natured principle: it illuminates without clarifying, reveals without orienting, and transmits both grace and pathology between the transpersonal and personal psyche. Jung’s alchemical writings treat moonlight as the atmosphere of Luna, the feminine arcane substance whose whitening work (albedo) is inseparable from danger — the speculum venenosum magnum naturae, the great poisonous mirror, in Paracelsus’s formulation that Jung quotes with evident fascination. Edinger reads the man who crouches in the moonlight and bays as a parable of what happens when the boundary between lunar awareness and lunacy dissolves. The Taoist I Ching mobilizes moonlight cosmologically, tracking the brightening and darkening of lunar light as an index of the advance and withdrawal of yang. In literary criticism, Bloom’s treatment of Hart Crane renders moonlight as a rhetorical figure for erotic inevitability and loss. The constellation of associations — madness, fertility, the feminine unconscious, the mediatrix between worlds, the numinous threshold — makes moonlight one of the corpus’s most densely overdetermined images.