Nor was its penetrative influence confined to the mystical schools. St. Thomas Aquinas, who accepts and expounds in the _Summa_ (I. _q._12. _a._5) the doctrine of the _lumen gloriæ_, is considerably indebted to Plotinus in several other particulars; though he cites him inaccurately, and does not seem to have known him at first hand. In a remarkable passage, which afterwards influenced one of the finest rhapsodies of Ruysbroeck, he has actually “lifted” the most celebrated phrase in the Sixth Ennead, and adapted it to the distinctively Christian and non-Platonic view of divine union, as a “mutual act” of God and the soul. “In a wonderful and unspeakable manner,” says St. Thomas of the soul in this place, “she both seizes and is seized upon, devours and is herself devoured, embraces and is violently embraced; and by the knot of love she unites herself with God, and _is with Him as the Alone with the Alone_.” It is in a later and less orthodox son of St. Dominic, the formidable and adventurous thinker Eckhart, that the influence of Plotinus on the mediæval mind is best seen: passing through him to Suso, Tauler, Ruysbroeck, and other mystics of the fourteenth century. Eckhart’s philosophy still provides one of the most suggestive glosses upon the Enneads. He made that distinction between the absolute and supra-personal Godhead and the God of devotion, which was almost inevitable for a Christian thinker trying to find a place in theology for the Neoplatonic One. The Godhead, he says, is “a non-God, a non-Spirit, a non-person, a non-image: a sheer pure One.” The Son, in whom “the Father becomes conscious of Himself,” combines the attributes of the Logos-Christ with those of the _Nous_. In Him are the archetypes of all created things. There is thus an emanation from the Godhead, through the Son, into creation. The soul’s destiny is exactly that conceived by Plotinus: it must ascend to the spiritual world, and through it to its origin, the One, “flowing back into the bottom of the bottomless fountain from which it flowed forth.” In Tauler and Suso, and especially in the great Flemish contemplative Ruysbroeck, these ideas—though modified by their inferior speculative ability and more ardent spirit of Christian devotion—are still strongly felt: and since their works and those of their disciples nourished many succeeding generations of contemplatives, through them the mystical side of the Neoplatonic tradition was handed down. In Ruysbroeck, with his threefold division of spiritual experience into “the moral life, the contemplative life, and the super-essential life,” and his astonishing and detailed descriptions of the soul’s achievement of the Essential Unity, the “death into the One through love,” the vision of Plotinus is fully baptized into the Catholic Church. In Jacob Boehme, who drew through Schwenkenfeld and Weigel from Eckhart and his school, the doctrine of the three worlds which forms the basis of his cosmology contains