> The thought experiment was scientific evidence?

Well, I guess you could even look at it that way (it is a question about thought that we are trying to answer, after all), but I'd tend to think that that is a category error, strictly speaking, in that we are dealing with a formal (language) system, so it's more on the proof side of things. Unless you consider it a question of finding agreement about definitions, in which case that thought experiment is simply an exercise in (empirically) determining the definition that you are using.

> Ah, well I am referring to the proposition as the content of the concept, and the content of the concept as not being dependent on its representation conceptually or syntactically. How something is conceptualized in the mind is not of current concern for my position.

Yes, I agree that how it is conceptualized is not (very) relevant (it kindof is, because complexity theory, essentially, but maybe we don't need to get into that?).

But it is relevant that it is represented, or at least I don't see any reason to think that representation is optional. That is to say: I have no idea what you are talking about when you are talking about immaterial Peano axioms. Every instance of Peano axioms that I can think of has a physical representation, just as every instance of cake that I can think of has physical representation. Making the assumption that there is such a thing as immaterial Peano axioms seems to me as reasonable as making the assumption that there is such a thing as immaterial cake. It is grammatically perfectly fine English to say "immaterial cake", but that's it, there is no content to those words.

> Well its not my definition. Is there a definition that satisfies you that I could consider co-opting?

Well, that's difficult, as ...

> Hmmm, interesting. I hadn't thought that it might be ambiguous. Why do you think it's ambiguous?

... there are so many ways in which people vary what exactly they mean by "exist".

As a random example, some people think that things that exist for a span of time that has no extent (like, 0 seconds) can be said to exist. In my book, that is a pretty useless definition, because it makes for a concept that cannot distinguish anything, but if that is your definition, an otherwise wrong argument might actually be correct--even though it doesn't tell you anything about useful notions of existence. And the argument that you are making seems to be of the kind where those details can make the difference between true and false.

> Well, if it is any consolation, you may note that I use "exists" in only one phrase that is used three times: "The potential for the universe being in a different state actually exists".

Which seems to be a central claim in all of this? But, I dunno, maybe we can try approaching it from the other end, and maybe that'll give me an idea what aspects of "existence" to ask for clarification on:

> That "the universe can change states" is known by observation.

Then ... in which sense isn't that scientific observation demonstrating the existence of the potential for the universe to be in different states?!

(Though I want to note that I probably would not use the word "existence" to describe the situation, as it smells a bit like a category error, specifically it smells like fallacious reification.)

> Define "should".

Haha, sorry, I didn't mean to sneak in another reference to morality or anything like that ;-)

I simply meant which reasons you would give to anyone who was interested, or possibly to humanity as a whole, to try and convince them to care about morality under that definition.