The One[edit]
One of the characteristic features of Plotinus' system, which was also taken up by subsequent Neoplatonists, is the doctrine of "the One" beyond being. For Plotinus, the first principle of reality is an utterly simple, ineffable, unknowable subsistence which is both the creative source and the teleological end of all existing things. Although, properly speaking, there is no name appropriate for the first principle, the most adequate names are "the One" or "the Good". The One is so simple that it cannot even be said to exist or to be a being. Rather, the creative principle of all things is beyond being, a notion which is derived from book VI of the Republic,[11] when, in the course of his famous analogy of the Sun, Plato says that the Good is beyond being (ἐπέκεινα τῆς οὐσίας
in power and dignity.[12] In Plotinus' model of reality, the One is the cause of the rest of reality, which takes the form of two subsequent "hypostases", Nous and Soul. Although Neoplatonists after Plotinus adhered to his cosmological scheme in its most general outline, later developments in the tradition also departed substantively from Plotinus' teachings in regards to significant philosophical issues, such as the nature of evil.