I talked as if Aristotle called the Prime Mover an external definition of morality. Actually, he would more likely call it the primal example of virtue. But he did say that the Mover spent eternity contemplating itself, so even without postulating a Nous as Plotinus does, you might get away with calling it a point-of-view on virtue. In fact, I don't think Aristotle distinguishes between the Prime Mover itself and a complete, accurate thought of the Prime Mover. I think that to him, contemplating it in fullness would mean having the Prime Mover itself in your soul. (Though this metaphor seems misleading. We might better say that your soul reaches out to include The Unmoved.) The map is the territory. This explains how he could locate thought-thinking-itself at the edge of the Ptolemaic world. The soul of the outermost sphere had the most complete picture of the Prime Mover, which means that it contains the Prime Mover.** Now, in Lovecraft's story, the human main character feels prejudice towards the primary body of the Soul and the Unmoved Mover, and thinks of them all in question-begging terms.
*Aleister Crowley associated his mystic goal with the Buddhist meditation on Consciousness, as well as those on Space, Nothing and the logically equivalent Neither P nor not-P. Aristotle, meanwhile, probably accepted initiation in the Eleusinian Mysteries. We can guess what that means, but we don't really know.
**Aristotle actually wrote about many Unmoved Movers and visible heavenly Souls. I'd call this a clash of principles. It seems unreasonable to Aristotle to say that one Unmoved Mover produces contrary motions. It seems unreasonable to Plotinus to say that pure thought-thinking-itself could include so much variation. Aristotle's objection no longer applies in our cosmology, at least not for the reasons he gave.