Any theory or model of reality, must take into account all of reality. It cannot depend on, or interact with, or export anything to, anything external. As that would not be a model of reality.
Yes, but nothing else that you've said follows from that. For example,
> One is, nothing can be created (no external source), or destroyed (no external dump), so any local structures can be transformed, but must be conserved in some way.
This is not a tautology, it is a metaphysical claim.
No, a model of reality cannot import something from anywhere else. Whatever is within reality, can only be determined by reality.
Nor can anything in reality, be exported outside of reality.
Reality is the one thing, the only thing, that cannot depend on anything undetermined or unchosen by itself.
The fact that reality must account for both itself, and any of its specifics, with no other domain to draw from, is a higher level of demand than for any other theory. That demand is a hard and unique constraint. A tautological constraint that is therefore usable as an axiom.
I mean, these are all just metaphysical claims. It also doesn't seem to address brute facts, which would be within reality, so it seems sort of pointless. It also doesn't seem to address infinite regresses.
Even if I grant your "axiom", which is just that "reality exclusively contains reality", nothing interesting follows from that for this conversation.
If there is only one such structure, if it is unique, then the question of its existence goes away. What would existence mean?
We would just know there was a unique self-consistent all consistent form covering structure. And that any form within that structure, with a sophisticating self-sensing self-interpretive ability, would experience its own existence.
Existence would then mean, part of the unique self-consistent, zero-information, independent of any externality, structure.
A perceived existence as a result of a unique tautological structure, not a result of any external composition.
And the phrase "I think therefore I am", would be tautological in both senses. As evidence. But also, as the actual meaning of existence. Given a self-aware form within a tautology, its perception of existence is the nature of existence.
Reality was always going to be something that forms structures, that are somehow inevitable, the only possibility, not something selected or manufactured by something else.
I mean, again, these are just claims and, once again, another brute fact.
> Reality was always going to be something that includes structure, that is somehow inevitable, the only possibility, not something selected or manufactured by something else.
This is a brute fact. I mean, literally it just is.
> One is, nothing can be created (no external source), or destroyed (no external dump), so any local structures can be transformed, but must be conserved in some way.
This is not a tautology, it is a metaphysical claim.