Path: ...!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!eternal-september.org!.POSTED!not-for-mail
From: olcott <polcott333@gmail.com>
Newsgroups: comp.theory
Subject: Re: DDD simulated by HHH cannot possibly halt (Halting Problem)
Date: Sun, 6 Apr 2025 11:12:36 -0500
Organization: A noiseless patient Spider
Lines: 60
Message-ID: <vsu95l$1c5kt$1@dont-email.me>
References: <vsnchj$23nrb$2@dont-email.me> <vso4a5$302lq$1@dont-email.me>
 <vsqhuu$1hl94$2@dont-email.me> <vsqknb$1ldpa$1@dont-email.me>
 <vsrmn8$2o2f2$1@dont-email.me> <vstku7$p4u7$1@dont-email.me>
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 8bit
Injection-Date: Sun, 06 Apr 2025 18:12:37 +0200 (CEST)
Injection-Info: dont-email.me; posting-host="27b06f6b2b272ffc2c3faed27fba4a45";
	logging-data="1447581"; mail-complaints-to="abuse@eternal-september.org";	posting-account="U2FsdGVkX18db/6t9WtC4y2Ee/A4EZf5"
User-Agent: Mozilla Thunderbird
Cancel-Lock: sha1:JLg5Nk8nmhJYSNx2it8M0jBvHrQ=
Content-Language: en-US
X-Antivirus: Norton (VPS 250406-4, 4/6/2025), Outbound message
In-Reply-To: <vstku7$p4u7$1@dont-email.me>
X-Antivirus-Status: Clean
Bytes: 3395

On 4/6/2025 5:27 AM, Mikko wrote:
> On 2025-04-05 16:45:28 +0000, olcott said:
> 
>> On 4/5/2025 2:05 AM, Mikko wrote:
>>> On 2025-04-05 06:18:06 +0000, olcott said:
>>>
>>>> On 4/4/2025 3:12 AM, Mikko wrote:
>>>>> On 2025-04-04 01:27:15 +0000, olcott said:
>>>>>
>>>>>> void DDD()
>>>>>> {
>>>>>>     HHH(DDD);
>>>>>>     return;
>>>>>> }
>>>>>>
>>>>>> Do you really think that anyone knowing the C
>>>>>> programming language is too stupid to see that
>>>>>> DDD simulated by HHH cannot possibly return?
>>>>>
>>>>> Anyone knowing the C language can see that if DDD() does not halt
>>>>> it means that HHH(DDD) does not halt. The knowledge that that
>>>>> means that HHH is not a decider is possible but not required.
>>>>>
>>>>
>>>> *Perpetually ignoring this is not any actual rebuttal at all*
>>>>
>>>> *Simulating termination analyzer Principle*
>>>> It is always correct for any simulating termination
>>>> analyzer to stop simulating and reject any input that
>>>> would otherwise prevent its own termination. The
>>>> only rebuttal to this is rejecting the notion that
>>>> deciders must always halt.
>>>
>>> Wrong, because a termination analyzer is not required to halt.
>>
>> Why say things that you know are untrue?
> 
> The term "termination analyzer" is used about programs that do not halt
> on every input. There is no strict derfiniton of the term so there is
> no requirement about halting.
> 
> On the first page of https://www.cs.princeton.edu/~zkincaid/pub/pldi21.pdf
> in the first parapgraph of Introduction:
> 
>     For example, termination analyzers may themselves fail to terminate on
>     some input programs, or ...
> 
>> A termination analyzer that doesn't halt
>> would flunk every proof of total program correctness.
> 
> There are no total termination analyzers.
> 

Total proof of correctness does not require a halt
decider, it only requires a termination analyzer
with inputs in its domain.

-- 
Copyright 2025 Olcott "Talent hits a target no one else can hit; Genius
hits a target no one else can see." Arthur Schopenhauer