Full Idea
We may not seek any point in space in which to seat the soul; it must be set outside of all space; its distinct quality, its separateness, its immateriality, demand that it be a thing alone, untouched by all of the bodily order.
Gist of Idea
The soul is outside of all of space, and has no connection to the bodily order
Source
Plotinus (The Enneads [c.245], 5.1.10)
Book Reference
Plotinus: 'The Enneads', ed/tr. Mackenna,Stephen [Penguin 1991], p.359
A Reaction
You can't get more dualist than that. He doesn't seem bothered about the interaction problem. He likens such influence to the radiation of the sun, rather than to physical movement.
Related Idea
Idea 21815 Because the One is immobile, it must create by radiation, light the sun producing light [Plotinus]