Here, I am not going to discuss the Christian God. — MoK
I am sort of Nietzschean when it comes to the God of the philosopher - everyone sort of makes up their own placeholders when they mean "God" in a philosophical argument. So if reference to "Father" not moving, "Son moved" as one and the same thing called "God" is off-putting because it admittedly sounds Christian, then all that was poor choice of words that didn't help me describe what I'm trying to say to you.
First of all, I agree, God, itself, changes, is moving. If someone else, like Aquinas or anyone thinks God can't move, or doesn't change at all, I am suspicious of what they mean if they mean an agent can create without moving; even creation from nothing doesn't mean an agent has not moved to effect something new, and therefore this agent has changed. So I agree with your ultimate conclusion.
And I agree that if you accept the premises of your argument, the conclusion follows.
When I talk about "God", since I am a believer, I am talking about something I think I know, in my case, as a Catholic, about some
one I think I know. So whether God changes or does not change has the meaning to me of getting to know God himself. Just to digress from the logic and metaphysics to let you know I am not merely playing here. (We are all playing here, but I, to myself, am not merely playing, even when I say "God".)
So it's an interesting question - we Catholics learn that God is eternally perfect, unmoved, and never changing, not deprived of anything ever that would beg something be moved. He could not move as he is already where he would move to. Etc., etc.
Yet, God must have moved in order for his creation from nothing to have been first not created, and then by God's movement, created. Without God changing, nothing would have been created. Nothing itself would have changed, if God were not changing nothing to something. And since nothing did change to something (because now is something), and only God could do it, God had to
do, had to
move, has to
change.
I like the use of "undecided state" to represent before nothing was changed into creation, because it makes an agent out of God, which makes sense for a creator God. Agents need hands to move things, even if those things are nothing into somethings. So agents, are moving, changing things, changing their hand from here, to now there, holding something, from what was nothing in hand.
But, if I am going to analyze not the validity of your argument, but whether I think you've created a proof for the motion of God who is creator, I think P2 is not necessary, and so C1 would not necessarily follow.
I think somehow, this argument could be shortened.
P1) God exists and is the creator of the creation from nothing
P2) If so, then there is a situation in which only God exists
C1) So, there is a situation in which only God exists
P3) If so, then God is in an undecided state about the act of creation when only God exists
P4) If so, then the act of creation is only possible if God goes from an undecided state to a decided state
C2) So, the act of creation is only possible if God goes from an undecided state to a decided state
P5) If so, then the act of creation requires a change in God
P6) If so, then God changes
C3) So, God changes — MoK
P1. God is the creator of creation from nothing. And this God exists. No reason to differ here and we are off to the races.
P2. If God exists and is the creator of creation from nothing, then there is a situation in which only God exists.
Although I understand why you are referring to a situation before creation as a situation in which God only exists; before anything else existed, there was nothing, but God, and if God created creation from nothing, then all that needed to be was God for there to be creation. I get it. Before many things were created, there was only one creator only, so "only God exists."
But couldn't God create all of creation from nothing, and yet not be the only thing that exists while he is doing it? Like this: before creation, there was God and a blob of X (imagine anything, in a blob or a heap if you will, shaped in some limited way, and imagine whatever you imagine as "God" next it, and imagine absolutely nothing else).
So P1 works still in the God plus blob pre-created situation; God can exist and be the creator of the creation from nothing, as long as God doesn't create anything using that blob of X. The problem with P2 (for me) is the "If so, then".
If God is the creator of the creation from nothing, it does not follow that, if so, then there is a situation in which only God exists. It could be otherwise.
Now we can assert P2 anyway and, like P1, just assert: 1, there exists a creator God, and 2, the God, before creation, was the only thing that existed.
But now C1 is not a logical conclusion from P1 plus P2, but is instead a restated of P2.
But let's move on anyway.
Let's assume, for the sake of arguing whether God as we conceive of it is changing or not, we have established that God exists, is a creator from nothing, and that prior to any such creation, "there is a situation in which God only exists."
P3 and the rest of the argument follow without any issues I can see.
I like the term "undecided state" because it requires both a Decider (presumably God), and a new state after a decision has been made. It works.
But it includes time, which may be fine, and necessary (as any change seems to require time be spent changing), but if time can be eliminated, maybe the point about God changing, even outside of time, would be made sharper.
At P3 you said:
If so,
then God is in an undecided state about the act of creation
when only God exists.
How about:
If so, God exists in relation to nothing (as only God exists from P2).
And then P4 would be:
If so, then, by creating, God exists in relation to the created things, (no longer in relation to nothing).
And then we need a new P5:
Created things exist.
C2: So, God changes.
So my totally new argument, based on yours, but left on the stove probably too long, (and certainly an analytic mess but I'm just spit-balling about "God" and we can work out the logic later if useful):
P1) God exists, and created things exist from nothing.
P2) There is the situation in which created things do not exist (have not been created).
C1) So, since God exists, God is the creator of the creation from nothing.
P3) If so, absent creation, God exists in relation to nothing.
P4) If so, then, by creating, God exists in relation to the created things.
P5) Created things exist.
C2) So, God changes. (from creator in relation to nothing, to creator in relation to things.)