Across the depth-psychology and philosophical corpus gathered in the Seba library, ‘The Good’ emerges not as a single doctrine but as a contested metaphysical apex and ethical criterion that each major tradition must define in opposition to rival claimants. Plotinus, the most systematic voice, elevates The Good above Intellect and Being altogether, positing it as the self-sufficient Fountain from which Beauty, Life, and Intellectual-Principle radiate downward — a formulation that Plato’s Republic anticipates when it declares the Form of the Good to exceed even essence in dignity and power. Platonic dialogues from the Gorgias onward contest whether The Good is identical with pleasure, honour, or wisdom, and consistently deny the equivalence. Stoic sources, represented by Long and Sedley, relocate The Good within rational nature and virtue, making it both intrinsically valuable and structurally distinct from the ‘preferred indifferents’ of natural impulse. Augustine absorbs and Christianises this hierarchy, grounding all finite goodness in its derivation from an incorruptible divine source. Nietzsche, sharply dissenting, genealogises ‘good’ as a power-coded caste distinction, while Jung, reading Nietzsche against the Christian privatio boni tradition, insists that an omnipotent deity cannot be solely good without surrendering half its power. The term thus marks a fault-line between metaphysical realism, ethical naturalism, and psychological critique.