This is one of those areas I don’t spend a lot of tortured thought on because I consider it a bit too ambitious to try to figure out the exact nature of deity. I’ll count myself lucky if I’m able to figure myself out and grow in my work with Them, or the One over one lifetime.

“Ultimate Reality is not Polytheistic or Nondual or One, it is all of them”
And this wonderful diversity is just the way I like it, a great, big, delicious Spiritual Gumbo! Ahhh.

Is there one Goddess or many?
Yes

“Spiritual Gumbo” ummm – I like that. I like it alot!

A few observations:
First, monotheism did not come falling out of the sky, it is a development from earlier polytheistic forms. Your opposition between the two is too strong IMHO. Yes, that may be your contemporary experience of it, but we are talking theology now
Second, you are conflating nondualism and monism. This is precisely the sticking point between Buddhism and Advaita Vedanta Hinduism. If you say “Not two” does that mean that you are saying “One” (Advaita) or is that going beyond the evidence? (Buddhism). (Contrary to popular perception, Buddhism does not say that “Not Two” leads to a “Void” or an “Emptiness” – it says that all statements are ultimately void of meaning. Including the one that says that all statements are …)
Finally, you are neglecting dualism. There are perfectly valid systems that have pushed dualism. Samkhya Hinduism, Jainism, Zoroastrianism all have strong dualistic tendencies. And let’s face it, in our non-mystical daily lives we are all de facto dualists!
Boiling all that down, the great divisions have been on whether there is a single reality, two realities or many realities.
(ignore the guy on the left shouting “there is NO reality!” He is just a many-realities-person in disguise)
If you say that reality is single, you have the problem of explaining the perception and experience of multiplicity. If reality is one, from where do we get the idea that it is many? How is it even possible for such an idea to arise within a perfect Oneness?
If there are two incompatible realities, your problem is to explain how interaction between them is even possible. How can Spirit move Body unless it partakes of bodiliness, in which case, is it still Spirit?
The same problem exists in a many-realities setup, but you can always specify an intermediate entity to uuuh, mediate between two entities. Of course, this only means that you need two inter-intermediate entities to mediate between the original entities and the intermediate. This gives us an infinite regression of entities. William of Ockham would have been disgusted.
But the sum of an infinitely regressing series is a finite number: 1/2 + 1/4 + 1/8 etc ad inf. = 1
Therefore polytheism = monism
PS First prize to the reader who spots the exact point where I rely on philosophical sleight-of hand, legerdemain and optical illusion!

people have reported mystical experiences of a One that is the Source of all things
And might not this be due to their having lived in a monotheistic worldview that rejects all other possibilities? With ‘One God’ as the default, their experience might easily fall into that paradigm – they might not be able to process it any other way.
I say this because it’s not my own experience. I’m into ecstatic practices and have had some incredibly powerful encounters with various Gods and Spirits, and I have had a moving experience of ‘oneness’ with *each* one of them, as well as a feeling of ‘oneness’ with the spiritual plane (the Otherworlds, or whatever we want to call it) that I encountered those beings on/in. But I have never had an experience of any Source of All Things.
I wasn’t raised in any religion (though, of course, it was all around me in the culture) and rejected Christianity at an early age, though I did keep having mystical experiences in Nature. Maybe that’s why monism doesn’t work for me.
But I agree that it’s fun to talk about this stuff, and that ultimately it really doesn’t matter. (grin)

I think that you have underscored what makes the various forms of Paganism vital spirituality movements these days–a range of common practices and outlooks rooted in those practices. A handy big bag of skill sets and ways of gaining experiences and wisdom through those experiences.
Even though I do hold to a relatively sophisticated outlook on metaphysics derived mostly from Hindu Tantra (non-dual), I have found that it matters not a whit as far as Neo-Pagan practice goes.
What’s more, in addition to this non-dualism, that gets to ultimates that are far, far distant from living in the world,I more usually identify as a polytheist. In my own practice, I work with a metapantheon of deities and powers each of whom is–in practice–determinedly, even cantankerously, separate and individual.
So, yes, talking these stories is intriguing and fun, but they do not commit us to the kinds of differences that inhibit lively shared practices!

While I was working on a response to Clasqm lot of other good remarks came in. Wonderful. But since I worked on it, everyone’s gonna get it…
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I think you misread me, Clasqm. I think I am well aware of the difference between Monism in the sense implied in the Dryghton and NonDualism – which is why I distinguished between them, although maybe not enough to really make the point. But I did not want to discuss NonDualism. Check my use of the term “or.” I needed to make room for it, but that was all.
My approach is to try and make sense of experience. For me, in matters spiritual, experience is primary. I admit to not being very interested in the details of subtle philosophical discussion.
Trying to discuss what the people who have the experience say is beyond words is almost guaranteed to lead to problems. Look at the problems we have when we discuss things we agree are amenable to linguistic description! Even so, I’ll try.
In terms of mystical experience, Monism Dryghton-style appears to be encountering the Godhead, that which is beyond all differentiation, and from which all comes. Personality – our own when and if we have the experience – remains. To me that means that any interpretation/description of the encounter will reflect who is talking and where they were at before it happened.
The NonDual as I have experienced it is different. I try and describe it as Experience without an experiencer. But that is inadequate as well. It was wonderful beyond words and utterly beyond words.
Monism in this sense is not ‘monotheism’ as it has historically been described: one God rather than many, a God being a personality with plans and preferences and distinct from the world, which in its strong form is an inherently violent rejection of other people’s religions. The Christians and Jews were not the first to resort to violence to suppress any other form of worship. Akhenaton, often described as the first monotheist, also used politics and violence to achieve what neither logic nor experience could accomplish. Hard monotheism seems unable to perpetuate itself based on experience alone.
Monism simply argues there is a Source for everything. In a way I think of it as a description of the ultimate Gestalt. Monists in this sense make no claims about that Source having a personality (an inherently absurd concept in my opinion). Monism has logical problems accounting for the many, but my post tried to address that issue. I like the way you solve that problem as well, though I am not logician enough to know if it works in our mental terms, but I have mathematically brilliant friends who say Zeno was right. http://en.wikipedia.org/wiki/Zeno%27s_paradoxes
However, I think you conflate two kinds of dualism. First, the dualism that describes having a perceiver and a perceived. Duality instead of NonDuality. Second, that which sees good and evil or their equivalents as fundamental. Some interpretations of Zoroastrianism that I have read say it is dualistic, some others argue it is ultimately monist. I happily leave that issue to the theologians and historians. My own suspicion is that dualism in the sense of good and bad is an reflection of the influence of agricultural society and the mass suffering it occasioned. It is rooted in trying to understand suffering, rather than in spiritual encounter. All I know of hunting and gathering societies, such as those that preceded agriculture, indicates they do not see the world in good/evil dichotomies. That came later.
Finally, I am deeply suspicious of any philosophical argument about the world that does not bring in experience as basic. We can get lost in our own categories and abstractions, and never return to the world we experience with others. Look at libertarians! I refer again to my photon example – if our logic cannot encompass the nature of a photon, why expect it to do justice to the Sacred?
For me, the bottom line is that people experience what we categorize as spiritual in terms of NonDuality, the One as Source (as with the Dryghton), and Gods (I would argue of those Christians that experience their God – in reality they experience different Gods. The God of the Quakers is not the God of the Catholics.) It seems likely that many very early cultures simply experienced the world as alive, perhaps as Presence. That certainly harmonizes with Monism.
In all honesty I consider monotheism a human construct in a way that Polytheism is not, for it arbitrarily privileges someone’s experience and denigrates everyone else’s – or it is the latching on to a book and denigrating all experience except what the book reports. Those Monotheists who become tolerant of other traditions seem to gravitate towards more mystical Monistic interpretations – and with that I have no problem. Alternatively they may argue that God has many plans for salvation. To me, that ultimately boils down into Monism, not monotheism.
We Pagans sometimes have personally experienced one deity, sometimes more than one, but we have no intrinsic problem with others’ reports of different experiences with different Gods. So as a Pagan I have a strong bias that any account must be able to respect the wide gamut of spiritual experience reported by people over the millennia, while being suspicious of too much theorizing about its character. My own approach is to try and discover the roomiest space possible within which we encounter the Sacred in whatever way it touches us.

Ultimately, whether or not I see God/Goddess/Spirit/Self as One or Many, it is that I experience It that is important. I don’t mind working within a set of seemingly contradictory modalities, and I don’t mind working with a seemingly contradictory or nonsensical set of Deities either. I also don’t mind others experiencing or doing the same, sharing their experiences, practices, and benefits of those experiences with me. This, I think, is one of the Paganism’s greatest features: that while we all experience spirituality subjectively, we can still experience it together whether in a circle, or grove, or as a whole community.
This came to me quite directly at Pagan Spirit Gathering when I attended a few years ago. There were people from every spiritual walk of life attending, and the invocation of the God/desses and Spirits allowed everyone to call in their Deity(ies, spirit guides, etc. So people did, from Pan to Anubis, Lupa to the archangels, even Jesus and Yahweh. I find comfort that the spiritual path I have embraced is, in itself, so embracing. Ultimately, to me, it doesn’t matter as much what faith you follow, but what you practice with that faith.
In terms of my personal faith, I see the Gods and spirits as many things at once that may be seen as contradictory. I can see and experience my God/desses as Imminent Divinity as I can archetypal figures as I can concepts. I don’t think that these viewpoints contradict, but enhance my experience and understanding of Divinity, but others have differing viewpoints, and I like to hear them.