NEOPLATONISM is the Platonic philosophy interpreted by Plotinus (205–270 CE), systematized in his Enneads and further developed by others through the sixth century. From the first century BCE, the "divine Plato" had been revived as the supreme religious and theological guide by pagan Middle Platonists; simultaneously Neo-Pythagorean philosophers were active. Plotinus was receptive to both these theistic and apophatic (negative) schools. He liked the Middle Platonist teaching of the transcendence of a Supreme Mind and Being called theos (God) possessing the Platonic Forms as divine Ideas. These Ideas became the basis for kataphatic (positive) theology and a doctrine of divine providence for a later period, not for Plotinus.

Realizing that unity must always precede plurality, however, Plotinus taught that the First Principle of reality, the One, or Good, transcends being and thought and is ineffable, indefinable, thereby contradicting Middle Platonism. This theory, original with Plotinus, was repeated by his...