Path: news.eternal-september.org!eternal-september.org!.POSTED!not-for-mail From: olcott Newsgroups: comp.theory Subject: Re: How do computations actually work? Date: Mon, 26 May 2025 13:07:59 -0500 Organization: A noiseless patient Spider Lines: 165 Message-ID: <1012alv$24geg$1@dont-email.me> References: <100l09v$2tae8$5@dont-email.me> <100l1ov$2ul3j$1@dont-email.me> <100l3jh$2v0e9$1@dont-email.me> <100l5c8$2ul3j$2@dont-email.me> <100l75g$2vpq3$1@dont-email.me> <100l887$2ul3i$2@dont-email.me> <100l9gh$30aak$1@dont-email.me> <100lc4o$30pgm$1@dont-email.me> <100ld1u$312c9$1@dont-email.me> <100lg4g$31jt3$1@dont-email.me> <100lkdv$32ib3$1@dont-email.me> <100lmif$32v06$1@dont-email.me> <100lmp3$32ven$1@dont-email.me> <100m319$38k55$2@dont-email.me> <87jz69xlpx.fsf@nosuchdomain.example.com> <100mder$39slu$2@dont-email.me> <100oipb$3oge1$1@dont-email.me> <100onkd$3t5cb$1@dont-email.me> <100p6vj$3vlgq$1@dont-email.me> <100q6b1$5buc$2@dont-email.me> <100rtvq$ji9l$1@dont-email.me> <100sod2$p071$6@dont-email.me> <100umo8$1a058$1@dont-email.me> <100vaoj$1d5lg$9@dont-email.me> <10119a9$1tver$1@dont-email.me> <10122jj$22da5$7@dont-email.me> <10123fp$22udp$2@dont-email.me> <10124o8$22da5$17@dont-email.me> <1012aat$24dfe$1@dont-email.me> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Injection-Date: Mon, 26 May 2025 20:08:00 +0200 (CEST) Injection-Info: dont-email.me; posting-host="64fd189e500b414701d6509a3265afae"; logging-data="2245072"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX1+yiMqeI0/B6vQn1AFzfMmn" User-Agent: Mozilla Thunderbird Cancel-Lock: sha1:vz7IC+1XRkDkQRWjfDiNW5hKvRE= In-Reply-To: <1012aat$24dfe$1@dont-email.me> X-Antivirus-Status: Clean Content-Language: en-US X-Antivirus: Norton (VPS 250525-10, 5/25/2025), Outbound message On 5/26/2025 1:02 PM, Fred. Zwarts wrote: > Op 26.mei.2025 om 18:26 schreef olcott: >> On 5/26/2025 11:05 AM, Fred. Zwarts wrote: >>> Op 26.mei.2025 om 17:50 schreef olcott: >>>> On 5/26/2025 3:38 AM, Mikko wrote: >>>>> On 2025-05-25 14:50:58 +0000, olcott said: >>>>> >>>>>> On 5/25/2025 4:09 AM, Mikko wrote: >>>>>>> On 2025-05-24 15:25:21 +0000, olcott said: >>>>>>> >>>>>>>> On 5/24/2025 2:54 AM, Mikko wrote: >>>>>>>>> On 2025-05-23 16:04:49 +0000, olcott said: >>>>>>>>> >>>>>>>>>> On 5/23/2025 2:09 AM, Mikko wrote: >>>>>>>>>>> On 2025-05-23 02:47:40 +0000, olcott said: >>>>>>>>>>> >>>>>>>>>>>> On 5/22/2025 8:24 PM, Mike Terry wrote: >>>>>>>>>>>>> On 22/05/2025 06:41, Richard Heathfield wrote: >>>>>>>>>>>>>> On 22/05/2025 06:23, Keith Thompson wrote: >>>>>>>>>>>>>>> Richard Heathfield writes: >>>>>>>>>>>>>>>> On 22/05/2025 00:14, olcott wrote: >>>>>>>>>>>>>>>>> On 5/21/2025 6:11 PM, Richard Heathfield wrote: >>>>>>>>>>>>>>> [...] >>>>>>>>>>>>>>>>>> Turing proved that what you're asking is impossible. >>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> That is not what he proved. >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> Then you'll be able to write a universal termination >>>>>>>>>>>>>>>> analyser that can >>>>>>>>>>>>>>>> correctly report for any program and any input whether >>>>>>>>>>>>>>>> it halts. Good >>>>>>>>>>>>>>>> luck with that. >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Not necessarily. >>>>>>>>>>>>>> >>>>>>>>>>>>>> Of course not. But I'm just reflecting. He seemed to think >>>>>>>>>>>>>> that my inability to write the kind of program Turing >>>>>>>>>>>>>> envisaged (an inability that I readily concede) is >>>>>>>>>>>>>> evidence for his argument. Well, what's sauce for the >>>>>>>>>>>>>> goose is sauce for the gander. >>>>>>>>>>>>>> >>>>>>>>>>>>>>> Even if olcott had refuted the proofs of the >>>>>>>>>>>>>>> insolvability of the Halting Problem -- or even if he had >>>>>>>>>>>>>>> proved >>>>>>>>>>>>>>> that a universal halt decider is possible >>>>>>>>>>>>>> >>>>>>>>>>>>>> And we both know what we both think of that idea. >>>>>>>>>>>>>> >>>>>>>>>>>>>>> -- that doesn't imply >>>>>>>>>>>>>>> that he or anyone else would be able to write one. >>>>>>>>>>>>>> >>>>>>>>>>>>>> Indeed. >>>>>>>>>>>>>> >>>>>>>>>>>>>>> I've never been entirely clear on what olcott is claiming. >>>>>>>>>>>>>> >>>>>>>>>>>>>> Nor I. Mike Terry seems to have a pretty good handle on >>>>>>>>>>>>>> it, but no matter how clearly he explains it to me my eyes >>>>>>>>>>>>>> glaze over and I start to snore. >>>>>>>>>>>>> >>>>>>>>>>>>> Hey, it's the way I tell 'em! >>>>>>>>>>>>> >>>>>>>>>>>>> Here's what the tabloids might have said about it, if it >>>>>>>>>>>>> had made the front pages when the story broke: >>>>>>>>>>>>> >>>>>>>>>>>>>   COMPUTER BOFFIN IS TURING IN HIS GRAVE! >>>>>>>>>>>>> >>>>>>>>>>>>>   An Internet crank claims to have refuted Linz HP proof by >>>>>>>>>>>>> creating a >>>>>>>>>>>>>   Halt Decider that CORRECTLY decides its own "impossible >>>>>>>>>>>>> input"! >>>>>>>>>>>>>   The computing world is underwhelmed. >>>>>>>>>>>>> >>>>>>>>>>>>> Better?  (Appologies for the headline, it's the best I >>>>>>>>>>>>> could come up with.) >>>>>>>>>>>>> >>>>>>>>>>>>> Mike. >>>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> There is a key detail about ALL of these proofs >>>>>>>>>>>> that no one has paid attention to for 90 years. >>>>>>>>>>>> >>>>>>>>>>>> It is impossible to define *AN INPUT* to HHH that >>>>>>>>>>>> does the opposite of whatever value that HHH returns. >>>>>>>>>>> >>>>>>>>>>> That is a key detail about HHH. Your HHH is not a part of >>>>>>>>>>> those proofs. >>>>>>>>>> >>>>>>>>>> All of the proofs work this same way. >>>>>>>>> >>>>>>>>> No, they don't. Some proofs derive the same conclusion with an >>>>>>>>> essentially >>>>>>>>> different approach. >>>>>>>>> >>>>>>>>> However, in spite of the differences, they do share a common >>>>>>>>> fieature: >>>>>>>>> your HHH is not a part of any of the proofs. >>>>>>>> >>>>>>>> All of the conventional proofs of the HP assume that >>>>>>>> there is an *input D* that can actually do the opposite >>>>>>>> of whatever value that HHH returns. >>>>>>> >>>>>>> Depends on what you mean by "conventional". If you merely mean >>>>>>> proofs >>>>>>> that apply ordinary logic then there are proofs with a different >>>>>>> strategy. If you mean only proofs that use the same strategy that >>>>>>> Turing used then you are closer to the truth. But there is no >>>>>>> assumption >>>>>>> about the exstence of such D. Its existence is proven. >>>>>> >>>>>> In seems that way until you pay much closer attention. >>>>> >>>>> No, it seems that way when you pay enough attention. >>>>> >>>>>> int main() >>>>>> { >>>>>>    DDD(); // The HHH that DDD calls cannot report on the >>>>>> }        // behavior of its caller because it cannot see >>>>>>           // is caller. >>>>> >>>>> If HHH is correctly constructed it does see DDD and everything DDD >>>>> calls. Nothing else is relevant. >>>>> >>>> >>>> Try to show how HHH can see anything about its own caller >>>> when HHH is not even allowed to look at its caller. >>>> >>> >>> It is irrelevant whether DDD is the caller of HHH or not. >>> int main() >>>   { >>>      HHH(DDD); >>>      return; >>>   } >>> >>> Now HHH is not called from HHH, but has the same input and it should >>> see that DDD includes the Halt7.c code, which aborts, so it should >>> see: a halting program. >> >> In other words you fail to understand that >> halting requires reaching a final halt state. >> > > In other words you fail to understand that if HHH fails to reach the > specified final state, that is an bug in HHH. The ONLY correct measure of correct emulation is the x86 language. _DDD() [00002192] 55 push ebp [00002193] 8bec mov ebp,esp [00002195] 6892210000 push 00002192 [0000219a] e833f4ffff call 000015d2 // call HHH [0000219f] 83c404 add esp,+04 [000021a2] 5d pop ebp [000021a3] c3 ret Size in bytes:(0018) [000021a3] When DDD is emulated by HHH according to the rules of the x86 language then (by definition) there is no bug in this emulation. -- ========== REMAINDER OF ARTICLE TRUNCATED ==========