[QUOTE=Twirlip;172434]Insofar as I understand it, I'd be inclined to agree with him on that. The asceticism of the Gnostics makes me uncomfortable; on the other hand, I see something real in the idea of the Demiurge as a kind of pseudo-Creator; so I'm looking for some system of ideas which has something like the latter, but nothing too much like the former.[/QUOTE]
If one wishes a more modern treatment of a philosophical and religious system compatible with Plotinus, I would suggest the process philosophy of A.N. Whitehead and the process theology of both Whitehead and Hartshorne. My own particular system of thought follows from Plato to Whitehead and from Plotinus to Hartshorne. I still tend to view Plotinus as a more religious and more mystical presentation of Plato.
Below just sort of a summary of my current understanding: with a few more modern process philosophy twists.
Unity is a central concept in Plotinus system of thought (monism) the One. Everything descends or emanates from the one and despite the apparent multiplicity of the lower levels of reality, Plotinus philosophy is essentially an ardent monist. The Intellect the level of reality directly below the One is the realm of the forms,. The forms are essentially the thought of the intellect. Soul is the level of reality below the intellect. The soul is among the most complex of the levels of reality and has multiplicity in the form of individual souls of humans and of other living things, and the world soul. The system of hierarchy in Plotinus is not a spatial temporal hierarchy but one of ontologic priority. The One is at the apex of the hierarchy and matter and the sensible world at the bottom of the hierarchy. In between lay the realms of the intellect and the soul. The intelligible world is a world which is non spatial temporal and in which eternal forms dwell. The sensible world is spatial and temporal and constantly in flux and change an imperfect and shadowy representation of the forms. Matter lies at the bottom of Plotinus hierarchy of levels of being. Matter is lack of being, privation, only potentiality, lacking form, lacking being. Matter is produced by the lower soul or nature (physis). Plotinus does not believe in evil as a force in the world. Rather evil is a form of privation, evil is identified with matter as lacking form and a type of non-being.
Human beings stand on the border between two realms the sensible and the intelligible. Some humans tend towards the realm of the intelligible and some tend to the realm of the sensible. One can intellectually ascend towards the higher levels of reality (i.e., soul, nous, the One) by philosophical reasoning, contemplation or in some cases mystical union. The ascent from the beauty of material or corporeal things to the notion of the Form of the beautiful is one example of the intellectual ascent from the particular to the unified concept a general principle in both the thought of Plotinus and or Plato. The intellectual life is the true life, the good life and the proper goal of human beings. For Plotinus the goal of human life is the liberation of the soul from its attachment to the body and to the realm of sense perception.
Plotinus holds that all souls are really one (sort of a one mind theory) . The individual souls of the creatures and the world souls are all really manifestations of the hypostasis soul. As one descends through the levels of reality from the completely unified One, there is the illusion of separation and of multiplicity but ultimately all is an emanation from the one.
Matter is "that which is not" without form, without being, pure chance, randomness, the absence of order. Order, form and being is brought to matter, from the intelligible realm. Matter the lowest of the levels of being is the negation of Oder and of Intelligibility. Order and form and being are brought into matter through process. Process is the method whereby that which is potential is brought into actuality. The collapse of the quantum probability into a discrete result or measurement is an example of potentiality (the realm of possibilities) collapsing into actuality (realm of sense experience). Actual events are never perfectly or fully determined and ordered. Events are the interaction between the order of the noumenal realm and the randomness of the material realm or the randomness inherent in nature. The universe is the conjunction of order (forms) and of randomness or the freedom (individual actualities or individual creatures) bringing the potential into the actual and producing novelty and creative advance into (forms most beautiful and wondrous).
That which is actual is that which can be experienced? Do the objects of thought, of the mind (noumena) exist? Are the objects of perception (phenomena) more real than the noumena? For Plato and for Plotinus the answer is the noumena are more real, exist in a higher level of reality than the phenomenal. The sensible world (the phenomenological) is a mere projection or reflection of the (noumenal) world. The realm of the intellect and of the forms is a higher ontologic level of being. Reality is unified in the One but in the lower levels of reality the unified principle is lost in a realm of apparent multiplicities and divisions. In the process of science we also believe in underlying principles in reality, we call them universal laws but we consider them to be lifeless. For the Greeks the underlying principles of reality were not lifeless but forms of mental ideals, the intellect and of soul.