Path: news.eternal-september.org!eternal-september.org!.POSTED!not-for-mail From: "Fred. Zwarts" Newsgroups: comp.theory Subject: Re: Unpartial Halt Deciders --- category error 2 Date: Sun, 20 Apr 2025 11:18:42 +0200 Organization: A noiseless patient Spider Lines: 123 Message-ID: References: <87zfgdnufj.fsf@nosuchdomain.example.com> <0JxMP.1398486$cgs7.284882@fx14.ams4> <87sem5nu3q.fsf@nosuchdomain.example.com> <438052adf5074f27313bbb52c9f14c20fcfa2418@i2pn2.org> <87plh7nbh4.fsf@nosuchdomain.example.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Injection-Date: Sun, 20 Apr 2025 11:18:43 +0200 (CEST) Injection-Info: dont-email.me; posting-host="1ca99acddb81e2218208b653e5254365"; logging-data="3650501"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX1+9v3zSEcioiEUTaLObWdmF" User-Agent: Mozilla Thunderbird Cancel-Lock: sha1:jZBuIm5PbrlqnN0kticJStTcS3U= In-Reply-To: Content-Language: nl, en-GB Op 19.apr.2025 om 22:58 schreef olcott: > On 4/19/2025 3:27 PM, Keith Thompson wrote: >> Mr Flibble writes: >>> On Sat, 19 Apr 2025 13:34:40 -0400, Richard Damon wrote: >>>> On 4/19/25 8:05 AM, Mr Flibble wrote: >>>>> On Sat, 19 Apr 2025 07:55:55 -0400, Richard Damon wrote: >> [...] >>>>>>> On 4/18/2025 2:32 PM, Keith Thompson wrote: >>>>>>>> Mr Flibble writes: >>>>>>>>> On Fri, 18 Apr 2025 12:25:36 -0700, Keith Thompson wrote: >>>>>>>>>> Mr Flibble writes: >>>>>>>>>>> I, aka Mr Flibble, have created a new computer science term, the >>>>>>>>>>> "Unpartial Halt Decider".  It is a Halt Decider over the domain >>>>>>>>>>> of all program-input pairs excluding pathological input (a >>>>>>>>>>> manifestation of the self referencial category error). >>>>>>>>>> [...] >>>>>>>>>> >>>>>>>>>> Do you have a rigorous definition of "pathological input"? >>>>>>>>>> >>>>>>>>>> Is there an algorithm to determine whether a given input is >>>>>>>>>> "pathological" or not? >>>>>>>>>> >>>>>>>>>> I could define an is_prime() function like this: >>>>>>>>>> >>>>>>>>>>        bool is_prime(int n) { >>>>>>>>>>            return n >= 3 && n % 2 == 1; >>>>>>>>>>            // returns true for odd numbers >= 3, false for >>>>>>>>>>            all others >>>>>>>>>>        } >>>>>>>>>> >>>>>>>>>> I'll just say that odd numbers that are not prime are >>>>>>>>>> pathological >>>>>>>>>> input, so I don't have to deal with them. >>>>>>>>> >>>>>>>>> Pathological input: >>>>>>>>> >>>>>>>>> Self-referencial to the decider. >>>>>>>> >>>>>>>> OK. >>>>>>>> >>>>>>>> Do you have a *rigorous* definition of "pathological input"? >>>>>>>> >>>>>>>> Is there an algorithm to determine whether a given input is >>>>>>>> "pathological" or not? >> [...] >>>>>> Examples are not definitions. >>>>>> >>>>>> And the problem is that the above example is itself a category error >>>>>> for the problem, as the DD provided above isn't a complete >>>>>> program, as >>>>>> it doesn't include the code for HHH as required, and when you include >>>>>> Halt7.c as part of the input, your HHH isn't a seperate program of >>>>>> its >>>>>> own, and thus doesn't have a Turing Complete range of inputs it can >>>>>> accept. >>>>>> >>>>>> Sorry, you are just showing you don't understand what it means to >>>>>> DEFINE something. >>>>> >>>>> Ah, the fundamental mistake you have been making all this time, Damon! >>>>> The self-referencial category error doesn't magically disappear by >>>>> providing source code rather than a run-time function address to the >>>>> decider; you are simply transforming the same input without affecting >>>>> the result. >>>>> >>>>> /Flibble >>>> >>>> And WHAT is the category error?  You stil can't show the difference in >>>> CATEGORY between what is allowed and what isn't, and in fact, you can't >>>> even precisely define what is and isn't allowed. >>>> >>>> Now, you also run into the issue that the "Olcott System" begins >>>> with an >>>> actual category error as we do not have the required two seperate >>>> programs of the "Decider" and the "Program to be decided on" given via >>>> representation as the input, as what you want to call that program >>>> to be >>>> decided isn't one without including the code of the decider it is >>>> using, >>>> and when you do include it, the arguments about no version of the >>>> decider being able to succeed is improper as it must always be that >>>> exact program that we started with, and thus it just FAILS to do a >>>> correct simulation, while a correct simulation of this exact input >>>> (which includes the ORIGINAL decider) will halt. >>>> >>>> Sorry, YOU are the one stuck with the fundamental mistake, or is it a >>>> funny mental mistake because you don't understand what you are talking >>>> about. >>> >>> The category error is extant over the domain of pathological inputs, no >>> matter what form those inputs take. >> >> That certain is a lot of words. >> >> Do you have a rigorous definition of "pathological input"? >> >> Is there an algorithm to determine whether a given input is >> "pathological" or not? >> >> "Yes" and "No" could be valid answers to either of those questions. >> Nothing you have written above is an answer to either of those >> questions. >> >> Are you able to answer those questions? >> > > Objective and Subjective Specifications > Eric C.R. Hehner > Department of Computer Science, University of Toronto > > (6) Can Carol correctly answer “no” to this (yes/no) question? > https://www.cs.toronto.edu/~hehner/OSS.pdf > > Pathological inputs are such that > Does the input halt on its input? > Both yes and no are the wrong answer. We are discussion inputs that describe a program. A specific input describes a specific program. For a specific program, one answer is always correct and the other one is wrong. If not, give an example of a specific program that both halts and does not halt. With this definition, pathological input does not exist.