From Theophany: The Neoplatonic Philosophy of Dionysius the Areopagite by Eric D. Perl:
It is not the contemplative inward turn but rather the externality of sense that separates the self, as subject, from all else, as external object.
…Intellection, then, is the apprehension of being, as a whole, in a complex but unified vision, and being itself is not a static series of lifeless forms but a communion of living intelligences.
…Intellect, or intellection, is thus genuinely analogous to vision, as a bringing together of subject and object. In sense vision, the subject “reaches out,” extends its gaze toward the object, and the object is taken into the subject’s awareness. Sense perception, as a mode of consciousness, is a partial overcoming of the separation between subject and object, self and reality. In intellectual vision or intuition, this is perfected, for there is no externality or “distance” between the self and reality, and so they are one.
…Intellect, therefore, is perfect consciousness in that it is the knowledge of being as its own content and therefore as itself. As such it is not an object fixed up above in metaphysical space but an activity that we ourselves, as consciousness, can be.
…The self, at the level of Intellect, is Intellect, which means that it is all things. Hence the ascent to Intellect is also an inward turn of consciousness, whereby we encounter reality not, as by sense, external to the self, but as the content of thought and thus within the self.
…Discursive reason, then, apprehends the same content as intellection, but in greater multiplicity. As the unfolded representation of intellection in soul, discursive reason functions as a mean between the unity of the forms in Intellect and the still greater dispersion at the level of sense.
…Intellect and sense, therefore, as modes of cognition, are not apprehensions of different “worlds” or sets of objects, but are more and less unified apprehensions of being, the only object of all cognition. The sensible cosmos as a whole is the sensuous apprehension of being, being as apprehended, most multiply, by sense, and the intelligible cosmos is the same content as apprehended, most unitarily, by intellectual intuition. The sensible and the intelligible are not two worlds, but rather the same reality, the manifestation of the One, apprehended in differing degrees of unity. The ascent to intellection is thus not a passage from one set of objects to another, but a gathering of the content of consciousness into greater unity.
…Plotinus summarizes this account of Intellect by saying that it is “as if there was one quality which held and kept intact all the qualities in itself, of sweetness along with fragrance, and was at once the quality of wine and the characters of all tastes, the sights of colours and all the awarenesses of touch, and all that hearings hear, all tunes and every rhythm.” This strikingly sensuous description of intelligible reality drives home the point that intellectual experience is far more rich, not less, than sense experience, because it apprehends in concentrated unity, although not without distinction, all the same content that sense apprehends in extended, “diluted” multiplicity.