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From: olcott <polcott333@gmail.com>
Newsgroups: comp.theory
Subject: Re: My reviewers think that halt deciders must report on the behavior
 of their caller
Date: Fri, 6 Jun 2025 12:11:17 -0500
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In-Reply-To: <101u6q3$2514a$1@dont-email.me>

On 6/6/2025 2:53 AM, Mikko wrote:
> On 2025-06-05 16:03:13 +0000, olcott said:
> 
>> On 6/5/2025 2:48 AM, Mikko wrote:
>>> On 2025-06-04 15:50:25 +0000, olcott said:
>>>
>>>> On 6/4/2025 2:04 AM, Mikko wrote:
>>>>> On 2025-06-03 21:39:46 +0000, olcott said:
>>>>>
>>>>>> They all say that HHH must report on the behavior of
>>>>>> direct execution of DDD()
>>>>>
>>>>> No, they don't say that. A halting decider (and a partial halting
>>>>> decider when it reports) must report whether the direct execution
>>>>> of the computation asked about terminates. Unless that computation
>>>>> happens to be DDD() it must report about another behaviour instead
>>>>> of DDD().
>>>>>
>>>>>> yet never bother to notice that the directly executed DDD() is
>>>>>> the caller of HHH(DDD).
>>>>>
>>>>> To say that nobody has noticed that is a lie. Perhaps they have not
>>>>> mentioned what is irrelevant to whatever they said. In particular,
>>>>> whether DDD() calls HHH(DDD) is irrelevant to the requirement that
>>>>> a halting decider must report about a direct exection of the
>>>>> computation the input specifies.
>>>>
>>>> *People have ignored this for 90 years*
>>>> *People have ignored this for 90 years*
>>>> *People have ignored this for 90 years*
>>>
>>> You have not identified anythhing relevant that has been ignored for
>>> 90 years. Seems that you ignore much of the discussions during those
>>> 90 years.
>>>
>>>> The only possible way that HHH can report on the
>>>> direct execution of DDD() is for HHH to report on
>>>> the behavior of its caller:
>>>
>>> The relevant question is not what HHH can report but what it does
>>> and what it is required. DDD() is known to halt so HHH(DDD) is
>>> required to report that it halts. But HHH(DDD) does not report so.
>>
>> The only DDD that is known to halt is the DDD
>> that calls HHH(DDD). HHH(DDD) IS NOT ACCOUNTABLE
>> FOR THE BEHAVIOR OF ITS CALLER.
> 
> Accountabiity is meaningless in the context of the halting problem.

Not at all. int sum(int x, int y) {return x + y;}
sum(3,4) is accountable to provide the sum of 3 + 4.
It is not accountable to provide the sum of 5 + 6.

Likewise HHH(DDD) is accountable for

<MIT Professor Sipser agreed to ONLY these verbatim words 10/13/2022>
     If simulating halt decider H correctly simulates its
     input D until H correctly determines that *its simulated D*
     *would never stop running unless aborted* then



> In that context it sufficient to note that the HHH does not correctly
> predict whether DDD halts.
> 
> However, one should understand that the behaviour of HHH(DDD) is an
> essential part of the behaviour of DDD. In particular, if HHH is a
> decider then DDD halts, though DDD may halt even if HHH is not a
> decider. But we know what HHH is so no if's about it are needed.
> 


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