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Re: Simply defining Gödel Incompleteness and Tarski Undefinability away V21

From André G. Isaak <agisaak@gm.invalid>
Newsgroups comp.theory, comp.ai.philosophy, comp.ai.nat-lang, sci.lang.semantics
Subject Re: Simply defining Gödel Incompleteness and Tarski Undefinability away V21
Date 2020-07-05 07:17 -0600
Organization Christians and Atheists United Against Creeping Agnosticism
Message-ID <rdsjtm$tv0$1@dont-email.me> (permalink)
References <TKydnUzgKLe6LZ3CnZ2dnUU7-S_NnZ2d@giganews.com> <rdqhbj$fnp$1@dont-email.me> <_MGdnVMFZeIeaZ3CnZ2dnUU7-WHNnZ2d@giganews.com>

Cross-posted to 4 groups.

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On 2020-07-04 15:28, olcott wrote:
> On 7/4/2020 1:21 PM, André G. Isaak wrote:
>> On 2020-07-04 10:36, olcott wrote:
>>> OVERVIEW:
>>> The sentence used in the SEP article to show the essential gist of 
>>> the 1931 Gödel incompleteness sentence
>>>
>>> https://plato.stanford.edu/entries/goedel-incompleteness/#FirIncTheCom
>>> (G) F ⊢ G_F ↔ ¬Prov_F(⌈G_F⌉)
>>>
>>> has been shown to not meet the standard definition of incompleteness:
>>
>> Umm. Of course this doesn't meet the definition of incompleteness. 
>> Incompleteness is a property of *systems*. What you've given above is 
>> a *statement*, not a formal system.
>>
>>> A theory T is incomplete if and only if there is some sentence φ such 
>>> that (T ⊬ φ) and (T ⊬ ¬φ). Because its negation is provable in F.
>>>
>>> This is not understood to be any failing of the simplified essence to 
>>> sufficiently correspond to the gist of the orginal Gödel sentence. It 
>>> is understood to mean that the Gödel incompleteness sentence does not 
>>> actually prove incompleteness at all.
>>
>> nor has it been claimed to prove incompleteness.
>>
>> The significance of
>>
>> F ⊢ G_F ↔ ¬Prov_F(⌈G_F⌉)
>>
>> Is that this statement can only be true if EITHER F is inconsistent OR 
>> if F is incomplete. And since Gödel provides a mechanical procedure 
>> for generating a proposition G_F which satisfies the above, ONE of 
>> these two things must be true.
>>
>> This only proves that F is incomplete once we add the stipulation that 
>> F is consistent. Thus, this only proves that F is incomplete once we 
>> recall Gödel claims his proof only holds true for CONSISTENT formal 
>> systems in which some minimal amount of arithmetic can be performed.
> 
> We are doing way too many steps at once we will never get resolution at 
> the current rate because we always slip-slid into extraneous side issues.

The problem is we seriously disagree on what count as side issues.

> Discussing this one step at a time until that step is 100% resolved.
> 
> Can you see how this can be existentially quantified:
> F ⊢ G_F ↔ ¬Prov_F(⌈G_F⌉) such as this: ∃G_F ∈ WFF(F) ¬Prov_F(⌈G_F⌉)

Why are you eliminating the biconditional here? Is there some 
justification for that?

André

-- 
To email remove 'invalid' & replace 'gm' with well known Google mail 
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Thread

Simply defining Gödel Incompleteness and Tarski Undefinability away V21 olcott <NoOne@NoWhere.com> - 2020-07-04 11:36 -0500
  Re: Simply defining Gödel Incompleteness and Tarski Undefinability away V21 André G. Isaak <agisaak@gm.invalid> - 2020-07-04 12:21 -0600
    Re: Simply defining Gödel Incompleteness and Tarski Undefinability away V21 olcott <NoOne@NoWhere.com> - 2020-07-04 16:28 -0500
      Re: Simply defining Gödel Incompleteness and Tarski Undefinability away V21 André G. Isaak <agisaak@gm.invalid> - 2020-07-05 07:17 -0600
        Re: Simply defining Gödel Incompleteness and Tarski Undefinability away V21 olcott <NoOne@NoWhere.com> - 2020-07-05 10:31 -0500
          Re: Simply defining Gödel Incompleteness and Tarski Undefinability away V21 André G. Isaak <agisaak@gm.invalid> - 2020-07-05 10:28 -0600
            Re: Simply defining Gödel Incompleteness and Tarski Undefinability away V21 olcott <NoOne@NoWhere.com> - 2020-07-05 11:42 -0500
              Re: Simply defining Gödel Incompleteness and Tarski Undefinability away V21 André G. Isaak <agisaak@gm.invalid> - 2020-07-05 10:53 -0600
                Re: Simply defining Gödel Incompleteness and Tarski Undefinability away V21 olcott <NoOne@NoWhere.com> - 2020-07-05 13:38 -0500
                Re: Simply defining Gödel Incompleteness and Tarski Undefinability away V21 André G. Isaak <agisaak@gm.invalid> - 2020-07-05 12:44 -0600
                Re: Simply defining Gödel Incompleteness and Tarski Undefinability away V21 olcott <NoOne@NoWhere.com> - 2020-07-05 13:56 -0500
                Re: Simply defining Gödel Incompleteness and Tarski Undefinability away V21 André G. Isaak <agisaak@gm.invalid> - 2020-07-05 13:16 -0600
                Re: Simply defining Gödel Incompleteness and Tarski Undefinability away V21 olcott <NoOne@NoWhere.com> - 2020-07-05 15:25 -0500
                Re: Simply defining Gödel Incompleteness and Tarski Undefinability away V21 André G. Isaak <agisaak@gm.invalid> - 2020-07-05 14:46 -0600
                Re: Simply defining Gödel Incompleteness and Tarski Undefinability away V21 olcott <NoOne@NoWhere.com> - 2020-07-05 16:08 -0500
                Re: Simply defining Gödel Incompleteness and Tarski Undefinability away V21 David Kleinecke <dkleinecke@gmail.com> - 2020-07-05 15:28 -0700
                Re: Simply defining Gödel Incompleteness and Tarski Undefinability away V21 (axiomatic basis of truth) olcott <NoOne@NoWhere.com> - 2020-07-05 17:50 -0500
                Re: Simply defining Gödel Incompleteness and Tarski Undefinability away V21 (axiomatic basis of truth) Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2020-07-05 17:13 -0700
                Re: Simply defining Gödel Incompleteness and Tarski Undefinability away V21 (axiomatic basis of truth) olcott <NoOne@NoWhere.com> - 2020-07-05 20:37 -0500
                Re: Simply defining Gödel Incompleteness and Tarski Undefinability away V21 (axiomatic basis of truth) André G. Isaak <agisaak@gm.invalid> - 2020-07-05 20:46 -0600
    Re: Simply defining Gödel Incompleteness and Tarski Undefinability away V21 olcott <NoOne@NoWhere.com> - 2020-07-04 17:39 -0500
    Re: Simply defining Gödel Incompleteness and Tarski Undefinability away V21 olcott <NoOne@NoWhere.com> - 2020-07-05 13:15 -0500

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