  There is another way in which Soul is related to Intellect as Intellect is related to the One.  Plotinus distinguishes between something’s internal and external activity (see V 4. 2, 27–33).  The (indescribable) internal activity of the One is its own hyper-intellectual existence.  Its external activity is just Intellect.  Similarly, Intellect’s internal activity is its contemplation of the Forms, and its external activity is found in every possible representation of the activity of being eternally identical with all that is intelligible (i.e., the Forms).  It is also found in the activity of soul, which as a principle of ‘external’ desire images the paradigmatic desire of Intellect.  Anything that is understandable is an external activity of Intellect; and any form of cognition of that is also an external activity of it.  The internal activity of Soul includes the plethora of psychical activities of all embodied living things.  The external activity of Soul is nature, which is just the intelligible structure of all that is other than soul in the sensible world, including both the bodies of things with soul and things without soul (see III 8. 2). The end of this process of diminishing activities is matter which is entirely bereft of form and so of intelligibility, but whose existence is ultimately owing to the One, via the instrumentality of Intellect and Soul. 