To understand and explain how precisely it is that mind and matter interact with one another in general is a considerable and perennial philosophical problem. Approaches to it that start from modern materialist assumptions have not yielded plausible answers any more readily than the Neoplatonists’ idealist perspective. Even though the Neoplatonists afforded it extensive treatment, they, unsurprisingly, have not satisfactorily explained it either. In a nutshell, the answer they gave has something to do with their fundamental understanding of the realm of the psychic. Plotinus in particular struggled in long and meandering treatises to explicate the precise functioning of the general phenomenon of what the ancients called “Soul” (psychê). Soul, a further hypostasis of being that effortlessly “falls out of” the inner activity of Consciousness in a similar way as Consciousness “fell out of” the First, is the link that facilitates the manifestation of form in matter. Their ingenious speculation about Soul, understood in its relationship to its cause (pure Consciousness) on the one hand and its effect (the emergence of the living material universe) on the other, lies at the heart of Neoplatonism. In a manner of speaking, Neoplatonism is nothing but a philosophy of the soul, or “psychology” in the original sense of that word.