A few days ago I read his chapter, The Mind-Space Analogy. Pretty damn brilliant. Of course, this book is based on Loy's philosophy doctoral dissertation, so I guess the brilliance isn't surprising.
Below I've shared Loy's analogy in his own words, albeit condensed. I've left out F and G of his analogy, which are another form of Mahayana Buddhism and Theism.
As you'll see, what Loy has done is imagine that something akin to "pure consciousness" actually exists.
This is more than an individual consciousness; it is an all-pervasive Mind-space that bears considerable resemblance to how the Absolute is viewed in the Eastern philosophies of Hindu Vedanta, Buddhism, and Taoism.
Forms of theism, of course, view the Absolute or God as an entity that is distinct from everything in existence. So the inclusive emptiness of Mind-space doesn't fit well with theism (though they can be crammed together with a bit of effort).
What I like most about Loy's analogy is how it points to this: a supposed experience of the Absolute can be interpreted in various ways. Meaning, this experience isn't revelatory of The Way Things Are, though religious true believers imagine that it is.
In my college days, for example, I had numerous psychedelic experiences that gave me a profoundly different view of the world. But I just looked upon these as impossible-to-describe experiences, not a glimpse of an objectively true alternative reality.
Everybody, repeat, everybody, has ineffable personal experiences. In fact, it can be argued that each and every experience is ineffable, since it is ours alone.
What Loy has done is point out how the same experience of his hypothetical Mind-space can be interpreted in various contradictory ways that correspond to how differing Eastern philosophical/religious perspectives view reality.
In short, it may indeed be possible for people to have a "non-dual" experience of the world, but this tells us little or nothing about what the world is like.
Here's a shortened version of Loy's Mind-Space analogy.
Comparing the Absolute to empty space is a metaphor that naturally suggests itself when we want to describe "something" which in itself has no characteristics.
...Thus space seems to be an excellent analogy for "empty nonduality." The analogy breaks down -- that is, we are reminded it is only an analogy -- in that our usual understanding of space conceives of it as an objectively existing medium that things are "in" and as having neither life nor awareness, whereas sunyata for Mahayana, Brahman for Vedanta and the Tao for Taoism are the ground of everything including all consciousness.
Of course, this is nothing other than the two sides of our familiar duality, the commonsense but problematical bifurcation between object (in this case, "material" space) and subject.
But let us use our imagination to eliminate this duality, by supposing that space is conscious. Let us suppose that as a result of some experience I realize that "my" consciousness is not mine at all but is an aspect of space itself.
...this experience of Mind-space seems to reveal "The Way Things Really Are." But if "I," having had this experience, were to be asked what I had realized, how would I answer? The point of this chapter is that this "Mind-space experience" lends itself to very different and contradictory descriptions.
In the following section I imagine some of the responses that might occur during a conversation among people who have had this experience and who have drawn metaphysical conclusions from it.
Speaker A [Sankkya-Yoga]: "There are two very different substances, both of which are uncaused and eternal and omnipresent, although they do not seem to interfere with each other or even interact. One is immutable and attributeless consciousness (Mind-space), which, I now realize, is what my mind always has been. The other is more difficult to characterize. I suppose we can call it an 'energy-stuff' or perhaps a fine 'matter-stuff'... now I realize that immutable consciousness and the constantly changing energy-stuff are quite different from each other and always have been."
Speaker B [Advaita Vedanta]: "Speaker A is mistaken. Only one thing is real: this immutable, attributeless Mind-space, which is what I and everything else really are. The constantly changing forms that arise within and from this Mind-space are simply illusions which delude us about what really is: they have no substance or reality of their own, for they are only phenomena that represent nothing but merely manifest the Mind-space... There is only this Mind-space, which is birthless and deathless and has no characteristics of its own."
Speaker C [Early Buddhism]: "What the others have called 'Mind-space' cannot really be said to exist, because it has no characteristics at all. It is so 'empty' that it is literally nothing, and how can nothing be 'real'? What 'I' have realized is that there is no 'I' and never was. All that does exist are those constantly changing phenomena -- or rather the 'attribute-elements' of which things are composed and which are now experienced clearly... However, it doesn't matter anymore what attributes arise or pass away, now that the sense of 'I' has evaporated and there is the deep peace of emptiness in its place."
Speaker D [Mahayana Buddhism]: "I agree with speaker C that speakers A and B, by referring to mind-space, have made something out of nothing -- that is, they have hypostatized emptiness into a substance. Yet I must also agree with speaker B that phenomena are not real, for they too are empty... Except for speaker A, we all agree that these appearances [of phenomena] do not represent any material substratum, but speaker C still tries to make these attributes into little substances of their own... Phenomena are illusory only if we are deluded into taking them as self-existing: now that we have realized they are empty appearances, we should accept them for what they are and be able to play with them freely. The dance may have no meaning, but there is still the empty dance."
Speaker E [ Taoism]: "I agree with speaker D, but he does not go far enough. He too is still one-sided. We have realized that the world is nondual, but we should not be so infatuated with this new way of experiencing that we become prejudiced against the more usual dualistic mode... Subject-object duality and the plurality of phenomena are also aspects of the world, and we should not dualistically reject one mode in favor of the other. Let us accept that there are these two ways of experiencing, without prejudice against either. Our aim should be to understand fully the relation between these two modes in order to be able to experience both."
Loy summarizes these perspectives by their answers to two questions:
Is Mind-space real?
Are Phenomena real?
Here's the answers.
A. Sankhya-Yoga: Yes, both Mind-space and Phenomena are real.
B. Advaita Vedanta: Yes, Mind-space is real. No, Phenomena are unreal.
C. Early Buddhism: No, Mind-space is unreal. Yes, Phenomena are real.
D. Mahayana Buddhism: No, both Mind-space and Phenomena are unreal.
E. Taoism: duality and nonduality are both "Real"
So take your pick.
A "mystical" experience of nonduality or cosmic oneness can be interpreted in various ways. We can accept the validity of the experience, yet be no closer to knowing the nature of absoute reality.