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From: Richard Heathfield <rjh@cpax.org.uk>
Newsgroups: comp.theory
Subject: Re: Halting Problem: What Constitutes Pathological Input
Date: Mon, 5 May 2025 23:50:17 +0100
Organization: Fix this later
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On 05/05/2025 23:02, Mr Flibble wrote:
> On Mon, 05 May 2025 22:51:12 +0100, Richard Heathfield wrote:

<snip>

>>> and I suspect you are being dishonest and know this already.
>>
>> On the contrary, when you talk about 'pathological input' you use the
>> term to describe uncomputable mappings between programs and termination
>> statuses, so you're rather closer to the truth than you perhaps
>> intended.
>>
>> To put it in terms you might be able to understand better:
>>
>> Turing hypothesised the existence of a universal halt decider,
>> but then showed that were such a decider to exist it would be possible
>> to use it to create a 'pathological input' that it couldn't decide, so
>> it follows that no decider can possibly be universal. /At best/, it can
>> decide for all non-pathological inputs.
> 
> I agree with that final statement:
> 
> "/At best/, it can decide for all non-pathological inputs."
> 
> However you and others have NOT made that statement in this forum up until
> this point; I wonder why that is? Learn by rote intellectual dishonesty
> perhaps?

You're quick to suggest dishonesty, aren't you?

But no, it's not dishonesty. My description (above) is a 
perfectly vanilla description of the standard halting problem, 
except that instead of 'undecidable' I wrote 'pathological'.

I deduce that you simply don't understand standard terminology.

-- 
Richard Heathfield
Email: rjh at cpax dot org dot uk
"Usenet is a strange place" - dmr 29 July 1999
Sig line 4 vacant - apply within