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TonesInDeepFreeze

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In set theory, equivalence does not imply equality. Here's the most trivial example: {{0 1}} is a partition of {0 1}. And that partition induces the e...
October 21, 2024 at 04:18
Then he's right. It takes only a moment to see that the salient feature of the argument is that it shifts from one sense of "if then" in one place to ...
October 21, 2024 at 04:00
Keep digging your sinkhole deeper.
October 21, 2024 at 03:47
I didn't ask for a definition of 'planar graph'. You didn't read what I said about this a few posts ago. You are a sinkhole.
October 20, 2024 at 20:26
Apparently, you don't recall the post in which I said that I'm willing to indulge you only up to the point that you go past the process of definitions...
October 20, 2024 at 20:25
You need to define "1D analogue of the established term "planar diagram"" in terms that don't presuppose any mathematics that you have not already def...
October 20, 2024 at 20:07
That relies on conflating two different senses of "if then": an everyday sense and the material conditional. I'll use '-->' for the everyday sense and...
October 20, 2024 at 19:56
That's BS. BS includes nonsense, doubletalk and falsity. And handwaving is not necessarily just lack of rigor to be supplied later. And you presume th...
October 20, 2024 at 19:07
You're conflating non-equivalent theorems. Theorem 1. The set of natural numbers is well ordered by the standard less than relation on the set of natu...
October 20, 2024 at 18:51
You seem not to understand how the mathematical method of handwaving works. It's not ZF or PA or one of those; it's the theory BS. You need to familia...
October 09, 2024 at 04:17
Thank you. You saved me a lot of time and effort. Because my prediction that you would resort to half-baked handwaving is confirmed, so I am done with...
October 09, 2024 at 02:15
Yes, the incompleteness theorem, when about PA in particular, is a meta-theorem about PA. If PA is consistent, then: PA |/- G PA |/- ~G PA |/- Con(PA)...
October 08, 2024 at 01:32
Of course, that is just sentential logic from: If PA is consistent then PA is incomplete. I'm not sure about that; I'd have to think about it. Correct...
October 05, 2024 at 08:26
In a given countable language, there are only countably many sentences. But there are uncountably many languages and systems, so it's trivial that the...
October 05, 2024 at 08:08
Here's what you wrote:
October 05, 2024 at 08:03
By millennia. But those concepts are not formal. You are so confused. T |= S stands for "T entails S" not "S is true in T". We know that 'true' and 'p...
October 05, 2024 at 08:02
You are very confused. Incompleteness is not a theorem of PA, unless PA is inconsistent. Incompleteness is ordinarily proved informally or formally in...
October 05, 2024 at 07:20
There are not only finitely many of them, and there are not uncountably many of them (there are only countably many sentences in the language), so the...
October 05, 2024 at 07:14
You keep using 'the soundness theorem' in a way that invites confusion. For the third time, the soundness theorem is: "If a sentence P is provable fro...
October 05, 2024 at 07:12
There are denumerably many of each.
October 05, 2024 at 06:46
Here's a breakdown: 'true' and 'false' here mean, respectively, 'true in the standard model for the language of PA' and 'false in the standard model f...
October 05, 2024 at 06:43
Where did Godel say that?
October 05, 2024 at 05:53
It wouldn't be used for arithmetic. But it would still have models if it is consistent. Irrelevant to what? Irrelevant to whom? It's relevant to whome...
October 05, 2024 at 05:07
The soundness theorem is "If a sentence P is provable from a set of sentences G, then all models of G are models of P". We don't prove that from PA. W...
October 05, 2024 at 04:43
There are two ways: (1) Prove a theorem from axioms. Then the theorem is true in any model in which the axioms are true. (2) Prove that the sentence i...
October 05, 2024 at 04:10
I accept your disclaimer. But I point out still that your comment gratuitously shifted from you to me. I asked for definitions and your retort was to ...
October 04, 2024 at 22:59
Like I said, I didn't get personal with you until you did with me.
October 04, 2024 at 22:52
Amazing that you got that exactly backwards.
October 04, 2024 at 22:51
You must mean that there's no point in you continuing. Others can choose for themselves.
October 04, 2024 at 22:45
In set theory, 'isomorphism' is not 'two things are the same that are not the same'. Rather, two things are similar; they have structures that are sim...
October 04, 2024 at 22:35
Just to be clear, the example doesn't assert that Venus is a star.
October 04, 2024 at 22:32
I put that in the category of "Don't micturate on me and tell me it's precipitation." It was a stupid comment: There's no reason to think I don't know...
October 04, 2024 at 22:30
I have no comment on Wittgenstein.
October 04, 2024 at 21:51
My posts were about correcting misstatements about the theorem and about the lack of clarity in your errant arguments about reactions to the theorem. ...
October 04, 2024 at 21:47
You don't know what you're talking about: (1) Of course I know the halting problem. You make no point with the false insinuation that I don't. (2) I k...
October 04, 2024 at 21:07
I wouldn't say that. (1) the set has only three members, not four, (2) the legs of the horse is not that set; rather the cardinality of the set of leg...
October 04, 2024 at 20:47
It seems that most often I'm not patient. In these situations, patience is a fault.
October 04, 2024 at 20:31
Two different senses of 'complete': (1) a theory T is complete iff for every sentence P in the language of T, either P is a theorem of T or ~P is a th...
October 04, 2024 at 16:12
It's not clear to me whether you're suggesting that my remarks were not pertinent. But in case you are: The conversation has had many subjects. You me...
October 04, 2024 at 06:15
What are the definitions of 'complete for a complexity class size' and 'consistent for a complexity class size' such that a logic can be complete and ...
October 04, 2024 at 05:53
How so? How would such a thing show that it is not the case that every consistent, formal theory sufficient for arithmetic is incomplete?
October 04, 2024 at 05:51
What's another? If it's just Hilbert's program, then why not just say that from the start? But then your reasoning about that limitation in connection...
October 04, 2024 at 05:37
Depends on what you mean by "everything". We were talking about incompleteness, in which context 'complete' and 'consistent' have certain definitions....
October 04, 2024 at 05:34
So one of the conclusions you are referring to is "incompleteness puts a hard limit on understanding the world"? Are there any writers who you think a...
October 04, 2024 at 05:16
What are complete and consistent, or incomplete or inconsistent are theories, not whatever "decidability for P v NP" is supposed to mean.
October 04, 2024 at 05:11
It is taken that incompleteness quashes Hilbert's program. I think it might depend on one's definition of 'logicism' whether incompleteness also quash...
October 04, 2024 at 05:09
What do you mean by 'decidable'? 'decidable' in context of incompleteness and computability theory has a definition. Is yours the same?
October 04, 2024 at 04:57
I don't know what that is supposed to mean. But incompleteness is not avoided by greater and greater proof capability. No matter how capable, if the s...
October 04, 2024 at 04:44
I don't know what that is supposed to mean, but, to be clear, the incompleteness theorem applies also to theories in higher order logic. Indeed, Godel...
October 04, 2024 at 04:39
Maybe you mean Rosser. Rosser improved Godel's theorem, but that has nothing to do with what I said in my post. That is very wrong and backwards. No c...
October 04, 2024 at 04:25