Read "Climbing the Stairway to Heaven", my 7-part review of Wilber's The Religion of Tomorrow (2017).
INTEGRAL WORLD: EXPLORING THEORIES OF EVERYTHING
An independent forum for a critical discussion of the integral philosophy of Ken Wilber
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is the author of Return to the One
, Life is Fair
and God's Whisper, Creation's Thunder.
More information about these books and Brian's current writing projects can be found at www.brianhines.com
, his website. A serious student of meditation, metaphysics, and philosophy for over thirty five years, Brian has a bachelor's degree in psychology/humanities, a master's degree in social work, and two years of doctoral-level training in systems science. He has been a research associate at the Oregon Health Sciences University, a manager with Oregon's health planning agency, and executive director of Oregon Health Decisions. Most recently, Brian was the communications director for Eco-Enterprises, Inc. This essay is a chapter in the book Spheres of Awareness: A Wilberian Integral Approach to Literature, Philosophy, Psychology, and Art
, University Press of America, 2009. Published on Integral World with permission of the author and the publisher.
Granted, Wilber gets a lot right about Plotinus. However, he also gets a lot wrong.
Ken Wilber is a great admirer of Plotinus, a 3rd century Greek philosopher. Much praise is lavished on Plotinus in Wilber's magnum opus, Sex, Ecology, Spirituality (SES). He says:
It is only a slight exaggeration to say that Plotinus took the best elements from each school [of philosophy in Alexandria] and jettisoned the rest….and, based on his own profound contemplative experiences, fashioned the whole thing into what can only be called an awesome vision, as coherent as it is beautifully compelling.
Absolutely true. I've got no problem with Wilber's passion for Plotinus, which I share. But I do have significant problems with Wilber's presentation of Plotinus's teachings. These teachings have come down to us in a collection of writings known as the Enneads—so-called because one of Plotinus's students, Porphyry, edited that collection into six sets of nine treatises each (enneads in Greek means “nines.”)
I've written one of the few popular (meaning non-scholarly and not, sadly, best-selling) books about Plotinus' philosophy, Return to the One. In translation I've read every word of the Enneads. I've studied most of the English-language books about Plotinus and his Neoplatonic teachings. My book has been favorably reviewed by scholars who are much more knowledgeable about Plotinus than I am.
So I can confidently say that the Plotinus described by Wilber in SES is quite different from the Plotinus that I know. Granted, Wilber gets a lot right about Plotinus. However, he also gets a lot wrong. Thus my purpose in writing this paper is to correct several misconceptions about Plotinus in SES.
My focus isn't on the bigger question of whether Wilber's integral vision is a correct view of the cosmos. What I mainly care about is whether Wilber's view of Plotinus is correct. That said, in SES Plotinus is held out as the preeminent Western exemplar of a nondual integrative vision. So if Plotinus actually isn't a non-dual philosopher, which I'll be arguing, then Wilber loses one of his main historical sources of support.
This leaves him with the Eastern non-dual schools such as Vedanta, Mahayana Buddhism, and Tantra. I wish Wilber had been content to let these philosophies of the East carry the banner of non-duality, for his attempts to force Plato and Plotinus into this vision of reality are strained at best.
Plotinus considered himself a Platonist, though modern scholars generally term him a Neoplatonist. According to Maria Luisa Gatti, Plotinus differs from Plato mainly in the elimination of politics from his philosophy, his more radical assertion that reality is monistic (a unified whole), and the spiritualization of his philosophical system.
Now, it might seem that Plotinus' monism is equivalent to Wilber's nonduality. But Wilber himself distinguishes the two:
There are no wholes, and there are no parts….There is no place where we can rest and say, “The universe's basic principle is Wholeness”….This prevents us from ever saying that the principle of the Whole rules the world, for it does not; any whole is a part, indefinitely.[ 3]
Well, Plotinus does say this:
For many does not come from many, but this [intelligible] many comes from what is not many. [V-3-16]
With both Plato and Plotinus what is “not many” is, logically, the One. The One, or God, is the Good that everyone is searching for.
Lloyd Gerson says, “The central notion of Plotinus's philosophy of religion is that of return. All creation is disposed by nature to return to the source whence it came, in so far as it is able.” 
Return: this is the central theme of the Enneads. In Wilber's way of speaking, Ascent. This is as true for Plato as for Plotinus, which calls into question Wilber's contention about Plato:
And so it was that Plato at this point united or integrated the path of Ascent with the path of Descent, giving an equal emphasis to the One and to the Many, to nirvana and to samsara. 
I'm no expert on Plato, but Lloyd Gerson is. In “What is Platonism?” Gerson says: “What is most distinctive about Platonism is that it is resolutely and irreducibly 'top-down' rather than 'bottom-up.'”[ 6] In other words, the phenomena of this world are explained through an appeal to intelligible (intellectual, immaterial, spiritual) principles.
Thus there is an inherent dualism in Platonism. By no means does Plato give equal emphasis to the One and the Many as Wilber claims. Gerson notes that Plato considers the sensible world to be an image produced by the intelligible world (as does Plotinus). So Plato's explanatory framework is definitively top-down, with the top of the One being the source of the down—the Many.
Wilber has a habit in SES of making broad-brush statements about Plato and Plotinus that aren't backed up by direct citations from these philosophers. For example, virtually every quotation in “The Two Legacies of Plato” section where Wilber claims that Plato was a balanced ascender and descender comes from Arthur Lovejoy, not Plato himself.
Here's what Plato himself writes in the Republic near the end of his famous Allegory of the Cave, after the prisoner has escaped from the shadows of this world and seen the light of the One:
Moreover, I said, you must not wonder that those who attain to this beatific vision are unwilling to descend to human affairs; for their souls are ever hastening into the upper world where they desire to dwell; which desire of theirs is very natural, if our allegory may be trusted.
Admittedly, neither Plato nor Plotinus is a full-blown ascender. Wilber correctly says that each has a profound regard for the Many. But this pales in comparison with their attraction for the source of the sensible world, Intellect (Spirit) and the One. It is possible to find selected passages in the writings of Plato and Plotinus that seem to support a nondual, ascent-and-descent-are-equal interpretation. But this isn't the way Plotinus's philosophy is best understood.
Stephen MacKenna, a translator of the Enneads, says that “Plotinus is often to be understood rather by swift and broad rushes of the mind—the mind trained to his methods—than by laborious word-racking investigation.” In other words, with Plotinus the adage “It's better to be roughly right than precisely wrong” holds true.
In that spirit, let's take a look at how Wilber is wrong about four key aspects of Plotinus's Neoplatonic philosophy: (1) Non-duality, (2) Wholes and parts, (3) Ascent and descent, and (4) Embracing the many. I have liberally quoted both Wilber and Plotinus because I wanted to present their positions in their own words.
Plotinus quotations from the Enneads are in italics. They end with a bracketed notation such as [IV-3-12] where the Roman numeral denotes the treatise, the middle number the section in the treatise, and the last number the chapter in the section. Most of the quotations are from A.H. Armstrong's translation, published by the Loeb Classical Library. When the notation is followed by an endnote, this means that the quotation is a Michael Chase translation included in Pierre Hadot's book, Plotinus or The Simplicity of Vision.
Wilber contends that Plotinus espouses non-dualism. The non-dual, says Wilber, is totally formless, boundless, and unmanifest, which naturally makes it difficult to pin down. Wilber resorts to descriptions such as:
This is not a particular stage among other stages—not their Goal, not their Source, not their Summit—but rather the Ground or Suchness or Isness of all stages, at all times, in all dimensions: the Being of all beings, the Condition of all conditions, the Nature of all natures. And that is the Nondual.[ 9]
Wilber says that someone who has experienced a non-dual realization (such as the Indian sage Ramana) sees the Formless and the entire world of manifest Form as not-two, advaita, non-dual: “When all things are nothing but God, there are then no things, and no God, but only this.”
He claims that Plotinus is a non-dualist: “The need to balance and unite Ascent and Descent, Eros and Agape, wisdom and compassion, transcendence and immanence—this Nondual integration is the great and enduring contribution of Plotinus.”
Yet actually Plotinus taught that the One is the highest reality. The One is the source of everything in existence and remains separate from all that has emanated from it:
All these things are the One and not the One: they are he because they come from him; they are not he, because it is by abiding in himself that he gives them. [V-2-2]
For from that true universe which is one this universe comes into existence, which is not truly one. [III-2-2]
And the All could not any more come into being if the origin did not remain by itself, different from it. [III-8-10]
Plotinus was a mystic philosopher who wrote in a dense, sometimes almost impenetrable, style. The Enneads was composed to address questions raised by students in his school who already were familiar with Plotinus's teachings. This book wasn't intended to be a cogent, systematic, easily understood description of Plotinus's philosophy (which it certainly isn't).
So Plotinus often is hard to pin down. For example, some scholars consider that he is more of a mystical monotheist than a monist. Mystical monotheism is, of course, even further away from non-dualism than is monism. The general scholarly consensus, though, is that monism best describes Plotinus's conception of reality: the cosmos is a unified whole that emanates from a single source, the One.
I agree that Plotinus doesn't seem to be a genuine monotheist. He often uses anthropomorphic words such as “he” and “father” when speaking of the One, but this is literary license. The One has no characteristics of any sort, personal or otherwise, because the One is pure and simple ineffable unity. It definitely is not all things, as Wilber implies when he terms Plotinus a non-dualist.
The One is both transcendent and immanent. The One is both in the world and apart from the world. The necessary “and's” in the previous sentences indicate that non-dualism is a non-starter when seeking a pithy description of Plotinus's philosophy.
Plotinus says that there always remains an element of otherness even after the most intimate union with the One. He asks whether Socrates will belong to the higher unity after he leaves this lower physical world. No, Plotinus answers, for this would mean that Socrates, and the soul of Socrates, would cease to exist just when he's attained to the very best. What's the point of merging with the One if you're not around to be conscious of it?
Rather, says Plotinus:
Now no real being ever ceases to be…but each remains distinct in otherness, having the same essential being. [IV-3-5]
So returning to the One doesn't mean becoming the One, or eliminating all distinctions between creator and created, as Wilber contends.
Wholes and parts
Wilber doesn't believe that the cosmos consists of wholes and parts. Instead, there are only holons, wholes that are parts of other wholes. So each whole is simultaneously a part, a whole/part, a holon. This contention supports Wilber's theory that reality is non-dual:
Thus, holons within holons within holons means that the world is without foundation in either wholes or parts (and as for any sort of “absolute reality” in the spiritual sense, we will see that it is neither whole nor part, neither one nor many, but pure groundless Emptiness, or radically nondual Spirit). 
When I read passages like this in SES—and there are many—I get the impression that Wilber's Buddhist leanings are a big part of the reason his interpretation of Plotinus is so askew. “Pure groundless Emptiness” is a Buddhist conception. Yet admittedly there are passages in the Enneads where Plotinus seems to speak of the possibility of experiencing a roughly similar state, such as:
There one can see both him [God] and oneself as it is right to see: the self glorified, full of intelligible light—but rather itself pure light—weightless, floating free, having become—but rather, being—a god. [VI-9-9]
Note, however, that Plotinus is speaking here of distinct entities. There is God and there is oneself. The self is realized as a god, not the god. Anything isn't everything; distinctions aren't erased; always there remains the unity that is the One and the multiplicity that is not the One.
Wilber, on the other hand, says that there are no individual entities anywhere in the cosmos. “Individual,” he notes, means not divisible or not separable. So by that definition he argues that there are no individuals, just holons, or dividuals. This is akin to the Buddhist idea of dependent origination, one of the central features of Mahayana Buddhism.
In his book The Emptiness of Emptiness, C.W. Huntington, Jr. describes dependent origination: “Nothing exists in and of itself, which is simply another way of saying that nothing possesses intrinsic being.” The nature of things is reciprocal dependence. Relationships are the sole reality, just as Wilber theorizes in SES. Plotinus has a markedly different view:
And we call it the First in the sense that it is simplest, and the Self-Sufficient, because it is not composed of a number of parts: for if it were, it would be dependent upon the things of which it was composed. [II-9-1]
For around Soul things come one after another: now Socrates, now a horse, always some particular reality; but Intellect [Spirit] is all things. It has therefore everything at rest in the same place, and it only is, and its “is” is for ever, and there is no place for the future for then too it is—or for the past—for nothing there has passed away—but all things remain stationary for ever, since they are the same, as if they were satisfied with themselves for being so. [V-1-4]
These quotations from the Enneads point to the three hypostases, or levels, of Plotinus's cosmology. The One, a.k.a. the First and the Good, is absolutely simple and single. This means that the One is independent and self-sufficient. Thus in no sense is the One a holon, for it neither has any parts nor any connection with parts. The One is completely unaffected by the lower levels of creation that have emanated from it. It is beyond being.
The second level, Intellect, a.k.a. Nous and Spirit, is true being. Plotinus says: Intellect and being are one and the same thing….The knowledge of things without matter is its objects. [V-4-2] Intellect is all things because it possesses the immaterial Forms that are the true foundation of physical reality. Without the Forms, matter would just be a formless glob of near-nothingness. The realm of Intellect is outside of time. So it only is.
Intellect, which I (like Wilber) prefer to term “Spirit,” never descends to the material world of time. Soul is the intermediary between Spirit and our world:
But Intellect as a whole is always above, and could never be outside its own world, but is settled as a whole above and communicates with things here through soul. [IV-3-12]
Only in the realm of Soul, which has both immaterial and material manifestations (the latter is what we call “nature”) is there a hint of holons in Plotinus's philosophy. For Soul is in time, where things appear one after another rather than being present all together as they are in the realm of Spirit.
Hence, Wilber's ever-changing holonic world is considered by Plotinus to be the lowest level of the cosmos. The higher levels, Spirit and the One, are unchanging, outside of time, detached from all that lies below.
This means that Spirit and the One would be unaffected if the entire physical universe were to go out of existence. Plotinus is a Platonist and, as noted before, Platonism is unequivocally a top-down philosophy. What is above controls what is below, never the reverse. So this is another reason why Wilber's contention that “the Kosmos is composed of holons, all the way up, all the way down”  is incompatible with Plotinus's teachings.
Wilber says that the way you tell what is higher and what is lower in a holistic sequence is to destroy a holon and see what remains. That which is higher also will be destroyed, while what is not destroyed will be lower. Plotinus holds the opposite view: the highest levels of the cosmos, Spirit and the One, wouldn't be affected in the slightest if everything lower were to be obliterated. Even the Soul of the All, which is directly responsible for creation of the physical universe, is completely detached from what transpires in materiality:
For he rules it [the universe] while abiding above. It is in this sort of way that it is ensouled; it has a soul which does not belong to it, but is present to it; it is mastered, not the master, possessed, not possessor. [IV-3-9]
Once again we see that Plotinus's Platonic conception of the cosmos is, unlike Wilber's, top-down and hierarchical. Mutual cause and effect only rules the roost in the lowest realm of creation.
The One is a whole without any parts, so has nothing that it can be affected by. Plotinus terms Spirit a One-Many that is a whole with parts (the Forms) inseparable from Spirit's very being. Again, no mutual holonic connections. Soul is more divided, a One and Many, yet the highest Soul—the Soul of the All—is unaffected by the Many.
Wilber says that it is wrong to call the sum total of events in the universe the “Whole,” for this implies the ultimate priority of wholeness over partness. Yet this is just what Plotinus teaches: the Whole is in charge, whether it be the wholeness of the Soul of the All, Spirit, or the One.
Ascent and Descent
Obviously the question of where divinity can be found is central to spirituality. People often speak of being on a spiritual path. If that path doesn't lead in the right direction, then efforts to traverse it are so much wasted motion.
Wilber argues that while the world's religions are diverse, there are only two basic spiritual paths: ascent and descent. Ascenders seek to leave this world behind and climb to the One, while descenders embrace the Many that is all around us.
Since Wilber holds that ultimate reality is non-dual, his recommended spiritual itinerary is to first ascend and then descend, seemingly now with the realization that the cosmic mountain you went up and down actually doesn't exist.
I say “seemingly” because it isn't clear in SES whether the One and Many are objective realities or subjective perceptions. That is, does the spiritual aspirant really return to the One and then descend again to the Many, or does he only journey in his own consciousness?
Sometimes Wilber implies that the One and Many are objectively real. For example, in discussing the mysticism of the pseudo-Dionysius (which is claimed to be virtually identical to that of Plotinus), Wilber says:
There is, of course, the perilous Ascent straight to the formless Godhead, and a perfect Descent to a loving embrace of the entire world of the Many—the standard message of all Nondual schools: transcend absolutely every single thing in the Kosmos, embrace absolutely every single thing in the Kosmos—with choiceless compassion or love.
It sounds here as if the One and the Many are both truly existent. However, in the following quotation Wilber seems to be saying that it's all a matter of subjective perception:
For Plotinus, “Ascent” does not mean a change of place or a change in location or a change from “this world” to an “other world.” It means a change in perception so that more and more of this world is perceived as the other world—more and more of this world is perceived as Perfectly Divine, until there is only the Perfectly Divine in all perception, “this world” and “that world” being utterly irrelevant, and the way up and the way down meeting in every single act of loving and choiceless and nondual awareness.
Here too, Wilber has gotten Plotinus wrong. First, Plotinus does indeed consider that spiritual ascent is to an “other world.” The intelligible world is the immaterial realm of Spirit. It is a real place. Plotinus says that in the spiritual world, as here on earth, one sees, hears, smells, tastes, and touches—but not with physical senses, for the human body has been left behind. He speaks of the soul putting on various bodies, some ethereal, some earthy.
For without body the soul is wholly in the intelligible world. [IV-5-1]
But it is to the other soul, which is not within the body, that belongs the drive towards the upper regions. [II-3-9] 
The souls when they have peeped out of the intelligible world go first to heaven, and when they have put on a body there go on by its means to earthier bodies, to the limit to which they extend themselves in length. [IV-7-10]
One can only assume that Wilber wasn't aware of these quotations from the Enneads when he wrote, “Plotinus goes on to point out that those who would find an 'other world' apart from 'this world' have missed the whole point. There is no 'this world' or 'other world'—it is all a matter of one's perception.”
Again, Wilber's interpretation is so distant from what Plotinus actually taught that it is, in my opinion, indefensible. While Wilber is correct when he says no movement in space takes place during the mystic's return to the One, for Plotinus the hypostases or levels of the cosmos definitely are not merely a matter of perception. Nowhere in the Enneads does Plotinus say, “After you return to the One you'll realize that that really isn't a One. Nor Spirit. Nor Soul. Non-dual awareness is all there is.”
Quite the contrary. Plotinus taught that the goal of human life is to leave this world and find a better one. His spiritual path is that of ascent. Every effort is to be directed toward separating soul from body and rising to the higher spiritual regions.
Since she wants to rise up to the Good, the soul disdains the beauties of this world. When she sees the beautiful things in this universe, she mistrusts them, for she sees that they are in flesh and in bodies, and that they are polluted by their present dwelling place.
…When the soul further sees that the beauties of this world flow away, she knows full well that the light which was shimmering upon them comes from elsewhere. Then the soul rises up to the other world, for she is clever at finding what she loves, and she does not give up before she has seized it, unless her love were somehow torn away from her. [VI-7-31][ 19]
Wilber says that the ascending program demands a withdrawal of attention from the senses, the body, the earth, and sexuality. This is precisely what Plotinus advocates. The soul's descent into the physical world isn't a condition to be celebrated, but a problem to be resolved. The sage will have to return to this world after communing with Spirit and the One if his destiny dictates further life with a body, but the goal is to be rid of flesh and bones altogether:
Courage, too, is not being afraid of death. And death is the separation of body and soul and a man does not fear this if he welcomes the prospect of being alone. [I-6-6]
Such is the life of the gods and of divine and happy men: release from the things down here below, a life which takes no pleasure in earthly things, a solitary flight to the Solitary One. [VI-9-11] 
Embracing the Many
Wilber's up and down approach to spirituality entails ascending to the One then descending back to the Many of this earthly existence—but with a different outlook. For now the One is perceived as the Many. This, says Wilber, is the seeing of compassion:
“But if wisdom sees that the Many is One, compassion knows that the One is the Many, that the One is expressed equally in each and every being, and so each is to be treated with compassion and care, not in any condescending fashion, but rather because each being, exactly as it is, is a perfect manifestation of Spirit. Thus compassion sees that the One is the Many.”[ 21]
This non-dual realization lies outside the sphere of logic. For in Wilber's spiritual schema each of these propositions is true: (1) the Many are illusory, (2) the One alone is real, and (3) the One is the Many. Thus reality is illusion.
I don't claim to understand what this means or whether it truly reflects a deep truth about the cosmos. However, I'm confident that this third stage of the spiritual path isn't part of Plotinus's teachings, notwithstanding Wilber's claim that it is.
Wilber says, “And thus Plotinus can easily make the nondual leap: 'Spirit not only engenders all things; it is all things.'”  The reader of SES is left with the impression that this is a quotation from the Enneads, but it isn't. When I turned to the endnote attached to this sentence I read, “He [Plotinus] refers to it as 'the within that is not within'—i.e. the within that is without, or subject-object nonduality.”
Probably Wilber is referring to this passage in the Enneads:
But those who do not see the whole only acknowledge the external impression, but those who are altogether, we may say, drunk and filled with the nectar, since the beauty has penetrated through the whole of their soul, are not simply spectators. For there is no longer one thing outside and another outside which is looking at it, but the keen sighted has what is seen within. [V-8-10]
Admittedly, a superficial reading of this quotation can lead to the impression that Plotinus is speaking of a state of consciousness akin to Wilber's non-dual embrace of the physical world's manyness. However, the section of the Enneads that this passage comes from is called “On the intelligible beauty.” The union of without and within takes place in the intelligible (spiritual) realm, not the material universe.
A few pages further on, Plotinus says, “If therefore sight is of something external we must not have sight, or only that which is identical with its object.” [V-8-11] This is the seeing of Intellect, whose vision is of unified immaterial Forms, a One-Many: not One and not Many. Yet not non-dual either.
But, as contemplation ascends from nature to soul, and soul to intellect, and the contemplations become always more intimate and united to the contemplators…it is clear that in intellect both are one. [III-8-8]
Recall that Intellect, or Spirit, is not of this world. Plotinus taught that Spirit always remains above the physical universe and communicates with things here through soul. So the mystic philosopher has to ascend to the spiritual realm in order to achieve a unified vision of reality.
It could perhaps be said that, in and of itself, life within the body is an evil, but that, thanks to virtue, the soul can come to be within the Good, not by living the life of the composite [of soul and body], but by separating herself from it already in this life. [I-7-3] 
Wilber claims that “the love we have for the One is extended equally to the Many, since they are ultimately non-two.”  This sentiment is far removed from Plotinus' oft-repeated message in the Enneads that the Good, or One, is what is truly lovable, not the manyness of materiality. For Plotinus, evil is a name given to the lower range of what might be termed the good scale. This varies from infinity with the One to essentially zero with undefined matter devoid of form.
Thus the physical universe is almost completely devoid of goodness. It is as far away from the Good as a soul can get. The sage seeks to detach himself from this world, not embrace it.
Since not only the Good exists, there must be the last end to the process of going out past it or if one prefers to put it like this, going down or going away: and this last, after which nothing else can come into being, is evil. [I-8-7]
Its [the last soul's] product is a living being, but a very imperfect one, and one which finds its own life disgusting since it is the worst of living things, ill-conditioned and savage, made of inferior matter, a sort of sediment of the prior realities, bitter and embittering. [II-3-17]
Yet somehow Wilber finds it possible to claim that Plotinus espouses an “unconditional embrace of this and any world.”  No, Plotinus doesn't. In SES Wilber cites Plotinus's attack on the Gnostics (who, according to Wilber, saw physical manifestation as nothing but evil shadows) as reflecting a non-dual outlook on the cosmos. Actually, the meaning of that attack is just the opposite.
For Plotinus chastises the Gnostics for having an unrealistic expectation of how good this world should be. They're upset because the universe is so imperfect, but Plotinus says this is the nature of images that are insubstantial reflections of a fundamental transcendent reality.
We cannot grant, either, that this universe had an evil origin because there are many unpleasant things in it: this is a judgment of people who rate it too highly, if they claim that it ought to be the same as the intelligible world and not only an image of it. [II-9-4]
Thus the section in the Enneads called “Against the Gnostics” really is a paean to the hierarchical diversity of the cosmos, not to non-duality. Since everything in creation is an emanation of the One, all is Good. In this sense, Plotinus does indeed advocate embracing the Many. But he says that this is akin to loving the children of a beloved father. The children are adored because they are offspring of the father, not because there is no distinction between him and them.
For anyone who feels affection for anything at all shows kindness to all that is akin to the object of his affection, and to the children of the father he loves. But every soul is a child of That Father. [II-9-16]
So Wilber is wrong when he claims that Plotinus holds the advaitist position that the One is the Many—Brahman is the World. Plotinus doesn't consider that the manifest creation is God, the creator. Rather, the world is kept in existence by God who remains distinct from what has emanated from him.
It is not contracting the divine into one but showing it in that multiplicity in which God himself has shown it, which is proper to those who know the power of God, inasmuch as, abiding who he is, he makes many gods, all depending upon himself and existing through him and from him. [II-9-9]
Plotinus taught that the wisest thing is to accept that this lowest level of creation, the physical universe, can't have the attributes of the higher realms. For if everything was the same, there wouldn't be a higher and lower—just One. But the One produces by necessity, just as cold comes from ice and scent from a flower. The emanations of the One should remind us that their source lies beyond.
The man who censures the nature of this universe does not know what he is doing, and how far this rash criticism of his goes. This is so because the Gnostics do not know that there is an order of firsts, seconds, and thirds in regular succession, and so on to the last, and that the things that are worse than the first should not be reviled; one should rather calmly and gently accept the nature of all things, and hurry on oneself to the first. [II-9-13]
There's no embrace of non-duality in this quotation. Instead, there's an acceptance of the necessary existence of Manyness combined with an urging to leave it behind and return to the One. Compassion, for Plotinus, has a Stoic cast that is quite different from Wilber's Buddhist interpretation.
As John Dillon puts it, “One feels of Plotinus that he would have gladly helped an old lady across the road—but he might very well fail to notice her at all. And if she were squashed by a passing wagon, he would remain quite unmoved.” 
Since Plotinus considers this world to be a shadow of substantial reality, earthly affairs should be viewed as akin to a stage production. Actors know that they are playing roles separate from their true selves. So are we all, until the soul is realized as the self—not the bodies with which we usually identify.
Just like on a theatre stage, that is how we must consider all murders and rapings and sackings of cities: these are all changes of scenery and costume, acted-out wailings and lamentations. In this world, in each event that happens to us in life, it is not the inner soul, but the outer shadow of a person which laments and grieves. [III-2-15] 
In key respects, Ken Wilber gets Plotinus wrong. Plotinus is a monist, not a non-dualist. Plotinus's One is the self-sufficient source of creation, not an interdependent holon. Plotinus's spiritual path is ascent, not ascent and descent. Plotinus espouses detachment from the material world, not an embrace of it.
Since Plotinus is a Platonist, Wilber's integral vision fails to encompass two central figures in Western philosophy whom Wilber erroneously puts forward as exemplars of non-duality. However, this doesn't mean that his vision is invalid. It just needs to stand on its own two feet and not lean so much on the support of Plotinus and Plato.
The introduction of Sex, Ecology, Spirituality (SES) says that “the beads of knowledge are already accepted: it is only necessary to provide the thread to string them together into a necklace.” Wilber says that his book is an attempt to string together such a necklace. The stringing together of a large share of diverse human knowledge is an immensely difficult task. Wilber is to be commended for attempting it.
However, the individual beads need to be depicted truly if the necklace's appearance is to be trusted. I've tried to demonstrate that Wilber's Plotinus bead, which occupies a prominent position in his integral schema, isn't an accurate representation of this Greek mystic philosopher's teachings. With Plotinus, Wilber has tried to pound a monistic peg into a non-dual hole. I hope Ken Wilber will reconsider his treatment of Plotinus in future editions of his books.
I began by saying that my focus isn't on whether Wilber's integral vision is a correct view of the cosmos. However, I can't resist ending with some observations concerning the question of whether non-duality truly is the foundational aspect of reality. No one knows for sure, of course. A Nobel prize awaits the person who can definitively prove the nature of what physics calls the Theory of Everything.
So hypotheses about the essential nature of the universe are all we have right now. Some are more compatible with current scientific understanding than others. As someone who believes that science and spirituality are complementary, not competing, approaches to comprehending reality, I am attracted to Plotinus's mystic philosophy because it meshes so well with modern science.
Shimon Malin, a physicist, has written about the relationship between science and Plotinus's teachings in his book, Nature Loves to Hide: Quantum Physics and the Nature of Reality, a Western Perspective. Malin says:
For Plotinus, the sensible world is a mere reflection of the noumenal; for science, the sensible is the real thing, the only reality there is. The world of science is the world as given by the senses. Oddly, however, the Nous [Intellect] is not entirely absent from it. The Nous did lose its life, but not its presence. The idea that the sensible world is sustained and directed by an invisible substratum is the fundamental premise of science. This invisible substratum is called “the laws of nature.”
These laws often are capable of being put in a precise mathematical form. Most mathematicians are Platonists who consider that mathematics, and by inference the laws of nature, reflects the reality of an unseen intelligible domain of reality. This is Plotinus's teaching also. As Malin puts it:
For Plotinus matter is not only that which is not, it is also the expression of pure chance, pure randomness, the absence of order. Order comes from the Intelligible realm; the order that is found in the sensible world is due to the presence of the Nous; matter, “the last of the Forms,” is the negation of Intelligibility and the negation of order. The framework of quantum physics is in full accord with this perspective.
So if I had to place a bet on which conception is closer to the truth, Wilber's non-duality or Plotinus's hierarchy of being (soul, spirit, and source—the One), I'd put my philosophical money on Plotinus. For the existence of the well-structured and seemingly unchanging laws of nature argues against Wilber's holonic, shape-shifting belief that the One is the Many.
There seem to be levels of being in the cosmos, some more real, permanent, and substantial than others. At the least, there are (1) laws of nature and (2) what is governed by those laws. Plotinus goes further and says that those laws are transmitted by soul from a transcendental Intellect that gets its power and wisdom from a even higher reality—the One.
As Wilber says, Plotinus's vision is coherent and compelling. I only wish that Wilber had presented that vision more accurately in Sex, Ecology, Spirituality. Plotinus deserves better.
Unless marked with an endnote, all Plotinus quotations are from: armstrong, A.H., translator. Plotinus I-VII. Seven volumes published by Loeb Classical Library. Cambridge: Harvard University Press, 1966-1988.
1. Wilber, Ken. Sex, Ecology, Spirituality. Boston: Shambala, 1995, p. 333.
2. Gatti, Maria Luisa. “Plotinus: The Platonic tradition and the foundation of Neoplatonism.” In Lloyd Gerson, editor, The Cambridge Companion to Plotinus. Cambridge: Cambridge University Press, 1966, p. 24.
3. Wilber, pp. 35-36.
4. Gerson, Lloyd. Plotinus. New York: Routledge, 1994, p. 203.
5. Wilber, p. 326.
6. Gerson, Lloyd P. "What is Platonism?" Journal of the History of Philosophy: Volume 43, Number 3, July 2005, pp. 253-276.
7. Jowett, Benjamin, translator, “Dialogues of Plato: The Republic VII.” In Great Books of the Western World, Plato, Vol. 7. Chicago: Encyclopedia Britannica, Inc., 1952, p. 389.
8. MacKenna, Stephen, translator. Plotinus: The Enneads. London: Faber and Faber Limited, 1966, p. xxii.
9. Wilber, p. 301.
10. Wilber, p. 309.
11. Wilber, p. 341.
12. Wilber, p. 36.
13. Huntington, Jr., C.W. The Emptiness of Emptiness. Honolulu: The University of Hawaii Press, 1989, p. 49.
14. Wilber, p. 38.
15. Wilber, p. 357.
16. Wilber, p. 361.
17. Hadot, Pierre. Plotinus or The Simplicity of Vision. Translated by Michael Chase. Chicago: The University of Chicago Press, 1993, p. 107.
18. Wilber, p. 343.
19. Hadot, p. 54.
20. Hadot, p. 67.
21. Wilber, p. 327.
22. Wilber, p. 335.
23. Wilber, p. 335.
24. Hadot, p. 108.
25. Wilber, p. 327.
26. Wilber, p. 336.
27. Dillon, John M. “An Ethic for the Late Antique Sage.” In Lloyd Gerson, editor, The Cambridge Companion to Plotinus. Cambridge: Cambridge University Press, 1996, p. 324.
28. Hadot, p. 105.
29. Wilber, p. ix.
30. Malin, Shimon. Nature Loves to Hide. New York: Oxford University Press, 2001, p. 202.
31. Malin, p. 204.