[Serious] Could an omnipotent and omniscient god prove that he was God?

[GrandizerII]

The Universe is everything that exists.  That's what the word means.  Uni means one and versus means turning.  The Latin universus means turning into one or whole.

Words can change meaning over time. Because of repeated suggestions of a multiverse in this day and age, the word "universe" has come to be understood as a part of reality and not the whole.

Either way, if you're still not ever sure what someone means by a particular word, it's always good to ask.

Now if you define the universe as only part of what exists then you need to say how you are aware of this other part or it's simply an arbitrary claim.

Nothing wrong with "arbitrary", as you defined it earlier. Something not having evidence for its existence doesn't make it non-existent. We could still use reason and intuition to judge the plausibility of its existence. Well, some of us non-Objectivists, at least.

If, in your view, the concept of 'universe' does not denote the totality, what does?  See how the analytic-synthetic dichotomy poisons one's mind.  If we define the universe as  Just part of what exists, what justifies doing this.  Nothing.  I'll tell you why this is done.  It's to make room for a god to exist and to try and escape from the law of identity and the primacy of existence but it doesn' work because it is a completely arbitrary definition, based on no objective inputs. It's just a game of manipulating words.

Thanks for sharing your personal opinion here, which is not supported by the evidence and therefore is "arbitrary".   

If you start counting existents.....1, 2, 3....however many you count it is always a specific quantity.  Infinity is not a specific quantity, it's not a number.  It does not exist in reality.  I agree that it does have a use in mathematics to denote the potential to carry a number sequence on indefintely

Infinity is an unlimited quantity. I didn't see any good argument for why an actual infinite is impossible.

What I see is you making an argument against potential infinity not being actual infinity, which I can agree with. If you start counting from the number one all the way into infinity, you will never reach some final destination called "infinity", true. But so what? This doesn't invalidate actual infinites.

We don't perceive the universe, we perceive existents.  And since we know that we aren't perceiving all that exists then by the law of identiy we know that some specific quantity of existents exist but we will never know what specific quantity is.  But we need a concept in order to denote the whole and that's what the concept 'universe' does.  To say that there is another realm of existence outside the universe is a contradiction.  If you are fine with holding a contradiction then there's no point in continuing the discussion because you have abandoned reason.

And do you really honestly think that I've been saying that there is another realm of existence beyond the whole of existence? Come on, man, be more charitable than that.

It's fine if you feel a discussion with me is futile, and you want to cease the discussion with me. You're a free person after all.

Big questions are "big" for a reason. They're not meant to be easy to answer, if at all possible. Objectivists are not the first, nor the last, to struggle with these.