Path: news.eternal-september.org!eternal-september.org!.POSTED!not-for-mail
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 10:58:31 +0300
Organization: -
Lines: 57
Message-ID: <101rin7$1dv72$1@dont-email.me>
References: <101nq32$99vd$1@dont-email.me> <101or6b$maj5$1@dont-email.me> <101pq02$ta6v$4@dont-email.me> <15abd00ec5b1e4a13892e85ee6ace9ac10d92c56@i2pn2.org> <101qu8f$15bg8$3@dont-email.me>
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8; format=flowed
Content-Transfer-Encoding: 8bit
Injection-Date: Thu, 05 Jun 2025 09:58:32 +0200 (CEST)
Injection-Info: dont-email.me; posting-host="0b51feb6db55b3f4c6d6423f3ba60ddb";
	logging-data="1506530"; mail-complaints-to="abuse@eternal-september.org";	posting-account="U2FsdGVkX18c3LS9dtpgMApygAttVMEz"
User-Agent: Unison/2.2
Cancel-Lock: sha1:F+AVtCkzVTiIj0cxPjF//6rwYP8=

On 2025-06-05 02:09:19 +0000, olcott said:

> On 6/4/2025 8:43 PM, Richard Damon wrote:
>> On 6/4/25 11:50 AM, olcott wrote:
>>> 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*
>>> 
>>> 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:
>> 
>> So?
>> 
>> It *IS* a fact that to be correct, it needs to answer about the direct 
>> executiom of the program that input represents.
>> 
>> That is DEFINITION.
> 
> Likewise with the definition of Russell's Paradox
> until ZFC showed that this definition is complete
> nonsense.

Russell's paradox is not complete nonsense. It has a very clear
meaning: a theory where the paradox or some variant of it can
be shown is inconsistent. If a theory is inconsistent then it
is good to know that it is inconsistent. Conversely, if one
wants to present a new set theory or a new type theory or a new
theory of semantics one should check that the Russell's paradox
is not there nor any simple variant (like Barber's paradox or
the word "heterologous").

-- 
Mikko