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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 10:53 -0600
Organization Christians and Atheists United Against Creeping Agnosticism
Message-ID <rdt0i2$bkg$1@dont-email.me> (permalink)
References (2 earlier) <_MGdnVMFZeIeaZ3CnZ2dnUU7-WHNnZ2d@giganews.com> <rdsjtm$tv0$1@dont-email.me> <P-OdnXX34sv9b5zCnZ2dnUU7-V_NnZ2d@giganews.com> <rdsv3j$2hb$1@dont-email.me> <prGdnfpbksBxn5_CnZ2dnUU7-XPNnZ2d@giganews.com>

Cross-posted to 4 groups.

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On 2020-07-05 10:42, olcott wrote:
> On 7/5/2020 11:28 AM, André G. Isaak wrote:
>> On 2020-07-05 09:31, olcott wrote:
>>> On 7/5/2020 8:17 AM, André G. Isaak wrote:
>>>> 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
>>>>
>>>
>>> This group may may be having network problems.
>>> It will not load in Chrome
>>>
>>>   ∃G_F ∈ WFF(F) ↔ ¬Prov_F(⌈G_F⌉)
>>
>> That's not even well formed.
>>
>> Also, since G_F refers to a specific expression, you don't want to use 
>> that as the name of a variable. I think what you want to say is:
>>
>> ∃φ (φ ↔ ¬Prov_F(⌈φ⌉))
>>
>> There is no need to include φ ∈ WFF(F) as it serves absolutely no 
>> purpose.
>>
>> André
>>
> 
> Since I view all of these things from the formalist approach of 
> operations on finite strings I assume that every variable refers to a
> random finite strings unless somehow specified otherwise.

The formalist approach doesn't involve 'random strings'. The formalist 
approach approach refers to a specific way of interpreting formal 
systems. Formal systems do not consist of 'random strings'.

> Here is the next step. every formal system has a corresponding algorithm.

I don't see any step at all. I see a link to a google search page. What 
is the supposed step involved here?

André

> Curry–Howard correspondence
> https://www.google.com/search?q=curry+hown+corrrespondence&rlz=1C1GCEJ_enUS813US813&oq=curry+hown+corrrespondence&aqs=chrome..69i57j0.8575j0j8&sourceid=chrome&ie=UTF-8 
> 
> 
> I don't know whether or not I am referring to Curry–Howard 
> correspondence or not. What I am referring to is that all of the same 
> operations that are applied to the WFF of a formal language to verify 
> that a proof exists can be applied by an algorithm on finite strings.
> 
> There is no special magical quality of a human mind such that a human 
> mind can perform a formal proof that an algorithm cannot.
> 
> 


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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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