What, then, is introversion? It is one of the two great modes under which the spiritual consciousness works. Plainly, any living sense of God’s presence must discern that Circle whose centre is everywhere, as both exterior and interior to the self. In Ruysbroeck’s own works we find a violent effort to express this ineffable fact of omnipresence, of a truly Transcendent yet truly Immanent Reality; an effort often involving a collision of imagery. God, he says, may be discovered at the soul’s apex, where He ‘eternally lives and reigns’; and the soul itself dwells _in_ God, ebbing and flowing, wandering and returning, within that Fathomless Ground. Yet none the less He comes to that soul from without; pouring in upon it like sunshine, inundating it with torrents of grace, seizing the separate entity and devouring whilst He feeds it; flashing out upon it in a tempest of love from the Empyrean Heaven, the Abyss of Being, where He dwells. “Present, yet absent; near, yet far!” exclaims St. Augustine. “Thou art the sky, and Thou art the nest as well!” says the great mystic poet of our own day. Whilst nearly all the mystics have possessed clear consciousness of this twofold revelation of the Divine Nature, and some have experienced by turns the ‘outward and upward’ rush and the inward retreat, temperamentally they usually lean towards one or other form of communion with God,—ecstasy or introversion. For one class, contact with Him seems primarily to involve an outgoing flight towards Transcendent Reality; an attitude of mind strongly marked in all contemplatives who are near to the Neoplatonic tradition—Plotinus, St. Basil, St. Macarius—and also in Richard Rolle and a few other mediæval types. These would agree with Dionysius the Areopagite that “we must contemplate things divine by our whole selves standing _out_ of our whole selves.” For the other class, the first necessity is a retreat of consciousness from the periphery, where it touches the world of appearance, to the centre, the Unity of Spirit or ‘Ground of the Soul,’ where human personality buds forth from the Essential World. True, this inturning of attention is but a preliminary to the self’s entrance upon that same Transcendent Region which the ecstatic claims that he touches in his upward flights. The introversive mystic, too, is destined to ‘sail the wild billows of the Sea Divine’; but here, in the deeps of his nature, he finds the door through which he must pass. Only by thus discovering the unity of his own nature can he give himself to that ‘tide of light’ which draws all things back to the One.