It's incredibly easy to sink into semantic quicksand when talking about this stuff. This is because the universe has played a trick on you by supplying you with a continual stream of overwhelming evidence that the universe is populated by material objects that exist in particular places at particular times, and that have a continuity of identity such that it makes sense to say things like, "The vase on that table exists." The reason that continuity of identity matters is that it's required to make sense of the phrase, "The vase on that table." For that phrase to make sense, the vase that is on the table now has to be the same vase that is there a microsecond from now. If this were not so, then the vase on the table at time T0 might have existed at T0, but at time T0+epsilon it no longer exists. Instead, it's a different vase that exists at T0+epsilon (and a different one yet again at time T0+2epsilon).
This probably sounds like I'm being pedantic, because it's just obvious that material objects like vases do have continuity of identity. The evidence for it is just overwhelming. But despite the overwhelming evidence, it is in fact not true. And you don't even have to get into quantum mechanics to see that it is not the case. All you have to do is to try to define what "the same thing" actually means. When you do this, you run headlong into the "ship of Theseus" problem, which is so-called because of the manner in which it was first described by Plutarch around the time of Christ:
The ship wherein Theseus and the youth of Athens returned [from Crete] had thirty oars, and was preserved by the Athenians down even to the time of Demetrius Phalereus, for they took away the old planks as they decayed, putting in new and stronger timber in their place, insomuch that this ship became a standing example among the philosophers, for the logical question of things that grow; one side holding that the ship remained the same, and the other contending that it was not the same.Replace the word "planks" with "atoms" and you have a modern version of this puzzle: if you replace every atom in an object with a different but identical atom, do you end up with the same object or a different object? The collection of atoms you end up with after the replacement process will be completely indistinguishable from the collection you started with, so on what possible basis could you call the new collection "different"?
This is not an academic question. The atoms in your own body are continually being replaced in exactly this way. None of the atoms in your body today are the same as the atoms in your body when you were born. In fact, even the arrangement of atoms in your body changes. So in what sense can you say that you are "the same person" that you were when you were born? Or even last year? Or yesterday? Or a minute ago?
Or consider this: suppose I take a tree and cut it down. Is it still a tree? Suppose I mill it into lumber and build a house out of it. At what point did it stop being a tree and start being a house?
OK, OK, I hear you saying, the temporal and spatial boundaries of the identities of things referred to by words are fuzzy, but surely that does not cast doubt on the proposition that while a collection of atoms is arranged as a tree or a house or whatever, that that tree or that house actually exists in point of metaphysical fact, does it? Well, yes, it does. Why? Because atoms themselves are just arrangements of sub-atomic "particles". (And, of course, I put "particles" in scare quotes because sub-atomic particles are not really particles, but I don't want to get lost in the quantum weeds.)
To take an example that is prosaic to the modern mind but would have been every bit as esoteric as quantum mechanics to a person living a mere 100 years ago, consider the question, "Does software exist?" Surely the answer is "yes". Surely humanity has not built a multi-billion-dollar industry on a delusions. Surely there is some salient difference between software and (say) leprechauns. But if you try to get a handle on what software actually is you will find it to be every bit as elusive as a leprechaun. What is software made out of? What is its mass? What color is it? (Notice that we can actually give a meaningful answer to that last question for leprechauns: they are green!)
No sane modern person can deny the existence of software. And yet it is clear that the manner in which software exists is very different from the manner in which trees and houses exist. They obey very different laws of physics. Trees and houses are made of atoms which obey conservation laws. Software is made of bits, which don't obey conservation laws.
But the manner-of-existence of trees and houses shares one very important feature with the manner-of-existence of software: both depend on arrangements. What determines if a particular collection of atoms is a tree or a house is their arrangement. What determines whether a particular collection of bits is Microsoft Word or Mozilla Firefox is their arrangement.
Arrangement is everything. Planet earth has had more or less the same repertoire of atoms since it was formed four billion years ago (modulo the odd asteroid) but an endless variety of different kinds of things that consisted of nothing more than those same old atoms arranging and re-arranging themselves into different patterns. (And, of course, the atoms themselves are just different arrangements (scientists call them "states") of the quantum wave function.)
However: just because arrangement is everything (or everything is an arrangement) doesn't mean that there aren't useful distinctions to be made between different kinds of arrangements. Atoms are arrangements (states -- same thing) of the quantum wave function, but the kinds of phenomena that the wave function can directly produce are very limited: a dozen or so fundamental particles that arrange themselves into a hundred or so (depending on how you count) different kinds of atoms. That's it. That's all quantum mechanics does on its own. Not really very interesting.
But once you get to atoms, something fundamentally new happens: you get chemistry. Atoms interact with each other in ways that are fundamentally different from the way in which the quantum wave function arranges itself to produce atoms. Of course, the behavior of atoms are still constrained by quantum mechanics. Nothing magic happens when atoms produce chemistry. But the level of complexity rises by orders of magnitude. This is what is meant by the slogan "classical reality emerges from the quantum wave function."
To get to us humans, you have to go through at least two more of these "quantum leaps" (no pun intended): you have to go from chemistry to life, and you have to go from life to brains. Each of these transitions introduces fundamentally new kinds of behavior which "emerge" each from the level before. Again, no magic, no suspension of the laws of physics, just ever increasing levels of complexity.
Brains are not the final step in this process, however. Mice have brains, but they can't do math. Eventually you get to brains that are big enough that they can emulate Turing machines and do math and other symbolic computations. Somewhere along that path they invent language as well. Once they've done that, multiple brains can arrange themselves into villages, city-states, corporations...
Arrangement is everything!
So... do you exist? Do atoms exist? Does life exist? Do corporations exist? Does music exist? Do leprechauns exist? Yes. All of these things exist. They all exist as arrangements of something. Leprechauns exist as ideas, as fiction, as arrangements of thoughts in people's brains. Brains exist as arrangements of atoms. Atoms exist as arrangements (states) of the wave function.
Each of these "levels" is an ontological category. The right question to ask is not, "Does X exist." The answer is always "yes". The right question is, "What is the nature of X's existence?" or "To which ontological category does X belong?"
So let us ask the right question: to which ontological category do you, the thing that is reading these words, belong? Most people think that they belong to the ontological category of material objects, that is, the same ontological category as trees and houses. But that is wrong. Your body belongs to that ontological category, but you -- the thing that is reading these words -- do not. The thing that is reading these words is not your body: if (and please pardon the gruesome imagery) someone amputated all of your limbs and replaced all of your internal organs with artificial equivalents, you would still be you. But if someone deprived you of oxygen long enough to render you brain-dead, you wouldn't. (That's why we talk about "kidney failure" but not "kidney death", "brain death" not "brain failure.") You are a computational process, reified as an arrangement of electrical impulses in a human brain. Because we do not yet know how to copy software out of brains the way we can out of computers, you (the software process) are tightly bound to your brain. And because we do not yet know how to replace all other parts of the human body, your brain is tightly bound to your body, and that is why you (the computational process) feel a particular kinship with your body. But nonetheless, you and your body are not only distinct, they exist in different ontological categories. Your body is a material object. You (the thing that is reading these words) aren't.
Some important things to note about ontological categories: once you get beyond the basics (QM -> atoms -> chemistry -> life -> brains) things get very complicated. It is not clear how many ontological categories there are beyond brains. Music, fiction, math, law and language are five different OCs that I can come up with just off the top of my head. There are probably more. The boundaries between them are not crisp, and they don't form a hierarchy. All of them fall into the meta-OC of "mental construct".
So, my claim about God is: God belongs in the ontological category of "myth" with is a subset of the ontological category of "fiction" which is a subset of the ontological category of "mental construct". And if any of that sounds at all like I'm being pejorative or dismissive about God then you have not understood a single word I've said.
This is not to say that you can't disagree with me. There are two ways you could do this:
1. You could argue that God belongs in a different ontological category. In which case you have to tell me which ontological category you think He belongs to.
2. You could argue that God transcends ontological categories, or that He is the sum total of all ontological categories. But if you want to take that position, then you will have to explain to me how that statement contains any information, because defined that way "God" seems to be nothing more than a synonym for "everything". (And so my next question will be: how can the Bible and Jesus -- or anything else for that matter -- possibly have any kind of privileged status with respect to "everything"?)
Let the games begin.