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From: Mikko <mikko.levanto@iki.fi>
Newsgroups: comp.theory
Subject: Re: My reviewers think that halt deciders must report on the behavior of their caller
Date: Thu, 5 Jun 2025 10:48:59 +0300
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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.

-- 
Mikko