Path: ...!feed.opticnetworks.net!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail From: olcott Newsgroups: comp.theory,sci.logic Subject: Re: D correctly simulated by H proved for THREE YEARS --- rewritten Date: Sat, 15 Jun 2024 09:48:52 -0500 Organization: A noiseless patient Spider Lines: 104 Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Injection-Date: Sat, 15 Jun 2024 16:48:52 +0200 (CEST) Injection-Info: dont-email.me; posting-host="65be3053bb2d9b452c13d5ddc3153d90"; logging-data="3682461"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX18WSMwfvRXk0H/mkjz8YMnu" User-Agent: Mozilla Thunderbird Cancel-Lock: sha1:HUj8ZN6maeJNlt/dqb2twU3GhZU= Content-Language: en-US In-Reply-To: Bytes: 5674 On 6/15/2024 9:37 AM, Fred. Zwarts wrote: > Op 15.jun.2024 om 16:13 schreef olcott: >> On 6/15/2024 9:06 AM, Fred. Zwarts wrote: >>> Op 15.jun.2024 om 14:12 schreef olcott: >>>> On 6/15/2024 4:03 AM, Fred. Zwarts wrote: >>>>> Op 14.jun.2024 om 22:46 schreef olcott: >>>>>> On 6/14/2024 3:03 PM, Fred. Zwarts wrote: >>>>>>> Op 14.jun.2024 om 21:18 schreef olcott: >>>>>>>> On 6/14/2024 2:00 PM, Fred. Zwarts wrote: >>>>>>>>> Op 14.jun.2024 om 14:49 schreef olcott: >>>>>>>>>> I ran the actual code to verify the facts. >>>>>>>>>> HH1(DD,DD) does not have a pathological relationship to its input >>>>>>>>>> thus this input terminates normally. >>>>>>>>> >>>>>>>>> Your terminology is confusing. What you call a "pathological >>>>>>>>> relationship" is that H must simulate itself. >>>>>>>>> >>>>>>>> >>>>>>>> *CONVENTIONAL TERMINOLOGY* >>>>>>>> For any program H that might determine whether programs halt, a >>>>>>>> "pathological" program D, called with some input, can pass its own >>>>>>>> source and its input to H and then specifically do the opposite >>>>>>>> of what >>>>>>>> H predicts D will do. No H can exist that handles this case. >>>>>>>> https://en.wikipedia.org/wiki/Halting_problem >>>>>>> >>>>>>> The problem is that your simulator does not even reach the >>>>>>> "pathological" part of D. >>>>>> >>>>>> That is not the problem that is the criterion measure of a solution. >>>>> >>>>> You are using the wrong criterion, because this wrong criterion >>>>> also also applies to other programs, without a "pathological" part. >>>>> >>>>>         int main() >>>>>         { >>>>>           return H(main, 0); >>>>>         } >>>>> >>>>> where you proved that H reports a false negative. >>>>> >>>>> So, your criterion has no relation with "pathological" programs. >>>>> >>>> >>>> This criteria works correctly for ALL input, including pathological >>>> main(). >>> >>> You are twisting your own words,because main is not "pathological". >>> You do not even understand you own definition of "pathological": >>> >>> Op 14.jun.2024 om 21:18 schreef olcott: >>>> >>>> *CONVENTIONAL TERMINOLOGY* >>>> For any program H that might determine whether programs halt, a >>>> "pathological" program D, called with some input, can pass its own >>>> source and its input to H and then specifically do the opposite of what >>>> H predicts D will do. No H can exist that handles this case. >>> >>> No high level programming skills are needed to see that there is no >>> part where main 'then specifically do the opposite of what H predicts >>> it will do'. >>> >>> It seems that you are changing the definition of "pathological" to >>> 'any program for which H returns a false negative', which then >>> becomes a tautology. >>> >> >> Any function that calls H specifies recursive simulation. > > Is this the new definition of "pathological"? *It is the same thing that I have been saying all along* 00 typedef void (*ptr)(); // pointer to void function 01 02 int HH(ptr P, ptr I); 03 04 void DDD(int (*x)()) 05 { 06 HH(x, x); 07 return; 08 } 09 10 int main() 11 { 12 HH(DDD,DDD); 13 } Line 12 main() invokes HH(DDD,DDD); that simulates DDD() *REPEAT UNTIL outer HH aborts* Line 06 simulated DDD() invokes simulated HH(DDD,DDD); that simulates DDD() DDD correctly simulated by HH never reaches its own "return" instruction and halts. -- Copyright 2024 Olcott "Talent hits a target no one else can hit; Genius hits a target no one else can see." Arthur Schopenhauer