Within the depth-psychology corpus, ‘Horizon’ operates simultaneously as a phenomenological structure, a cosmological metaphor, and a psychological figure for the boundary between the known and the yet-to-be-known. The term’s most rigorous elaboration arrives through Heidegger’s analysis of temporality, where each ecstasis of time — past, present, future — opens toward a specific ‘horizon,’ making the structure of existence irreducibly open and self-transcending. Merleau-Ponty extends this into perceptual theory, treating the horizon as the condition of possibility for object-identity: the object-horizon structure is not an obstacle but the very medium of disclosure, ensuring that to see is always to see from within a field that exceeds any single view. Jonas, via Thompson, carries the concept into biology, arguing that life itself ‘entertains horizons’ beyond its point-identity — self-transcendence is constitutive of organism. Von Franz employs horizon as a psychological term for the range of consciousness available to a type, while Abram reads the visible horizon phenomenologically as a threshold joining presence to the inexhaustible beyond. In astrology-adjacent literature, the horizon has a literal architectural function — the birth-chart’s horizontal axis dividing subjective from objective realms — giving the term an embodied cosmological valence. The tensions are genuine: Is horizon a limit or an opening? Does it constrain or liberate? Von Franz and Heidegger agree, against the puer’s fear, that genuine horizon-widening follows from accepting finite constraints.