Path: ...!weretis.net!feeder9.news.weretis.net!feeder8.news.weretis.net!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail From: olcott Newsgroups: comp.theory Subject: Re: Liar detector: Fred, Richard, Joes and Alan --- Ben's agreement Date: Fri, 12 Jul 2024 08:07:59 -0500 Organization: A noiseless patient Spider Lines: 115 Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Injection-Date: Fri, 12 Jul 2024 15:08:00 +0200 (CEST) Injection-Info: dont-email.me; posting-host="a53340e46817c86b736359d5ee28d54a"; logging-data="3173309"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX18u+zZetsd74Aevv0u7gipG" User-Agent: Mozilla Thunderbird Cancel-Lock: sha1:cchwIjlRR7EBsbyp0WHVz74kq5c= Content-Language: en-US In-Reply-To: Bytes: 5697 On 7/12/2024 2:55 AM, Mikko wrote: > On 2024-07-11 14:16:34 +0000, olcott said: > >> On 7/11/2024 1:50 AM, Mikko wrote: >>> On 2024-07-10 13:37:30 +0000, olcott said: >>> >>>> On 7/10/2024 2:18 AM, Mikko wrote: >>>>> On 2024-07-09 14:14:16 +0000, olcott said: >>>>> >>>>>> On 7/9/2024 1:14 AM, Mikko wrote: >>>>>>> On 2024-07-08 17:36:58 +0000, olcott said: >>>>>>> >>>>>>>> On 7/8/2024 11:16 AM, Fred. Zwarts wrote: >>>>>>>>> Op 08.jul.2024 om 18:07 schreef olcott: >>>>>>>>>> >>>>>>>>>> Try to show how infinity is one cycle too soon. >>>>>>>>>> >>>>>>>>> You believe that two equals infinity. >>>>>>>> >>>>>>>> void Infinite_Loop() >>>>>>>> { >>>>>>>>    HERE: goto HERE; >>>>>>>> } >>>>>>>> >>>>>>>> void Infinite_Recursion() >>>>>>>> { >>>>>>>>    Infinite_Recursion(); >>>>>>>> } >>>>>>>> >>>>>>>> void DDD() >>>>>>>> { >>>>>>>>    HHH(DDD); >>>>>>>> } >>>>>>>> >>>>>>>> Two cycles is enough to correctly determine that none >>>>>>>> of the above functions correctly emulated by HHH can >>>>>>>> possibly halt. >>>>>>>> >>>>>>>> That you don't see this is ignorance or deception. >>>>>>> >>>>>>> There is an important detail that determines whether an infinite >>>>>>> execution can be inferred. That is best illustrated by the following >>>>>>> examples: >>>>>>> >>>>>>> void Finite_Loop() >>>>>>> { >>>>>>>   int x = 10000; >>>>>>> HERE: >>>>>>>   if (x > 0) { >>>>>>>     x--; >>>>>>>     goto HERE; >>>>>>>   } >>>>>>> } >>>>>>> >>>>>>> void Finite_Recursion(int n) >>>>>>> { >>>>>>>   if (n > 0) { >>>>>>>     Finite_Recursion(n + 1); >>>>>>>   } >>>>>>> } >>>>>>> >>>>>>> void DDD() >>>>>>> { >>>>>>>   HHH(DDD); // HHH detects recursive simulation and then >>>>>>> simulates no more >>>>>>> } >>>>>>> >>>>>>> The important difference is that in my examples there is a >>>>>>> conditional >>>>>>> instruction that can (and does) prevent infinite exectuion. >>>>>>> >>>>>> >>>>>> When we ask: >>>>>> Does the call from DDD emulated by HHH to HHH(DDD) return? >>>>> >>>>> Why would anyone ask that? A question should make clear its topic. >>>>> Instead one could ask whether HHH can fully emulate DDD if that is >>>>> what one wants to know. Or one may think that HHH and DDD are so >>>>> unimteresting that there is no point to ask anyting about them. >>>> >>>> A correct emulator can correctly any correct x86 instructions. >>>> When it emulates non-halting code then itself does not halt. >>> >>> Not quite right but should be easy to fix. There should be a verb >>> before "any", >>> for example "execute". Of course there still is a probelm with the >>> meaning >>> "any correct x86 instructions". Intel may publish a new x86 processor >>> that has >>> instructios that the emulator cannot know but are nevertheless >>> correct x86 >>> instructions because Intel says so. In the second sentence "it" >>> should be used >>> istead of "itself". >>> >> >> Intel has already done this and they call this x64. >> A 1907 Model-T Ford cannot have upgrades and still >> be a 1907 model-T Ford. Likewise for the x86 language. > > A new version of a 1907 Model-T Ford is possible and can have the same name > except that the "1907" must be replaced as it refers to the year. That the > "Model-T" is also replaced is a free chioce of Ford. > > Likewise Intel is free to call a new processor whatever they want to > call it. > The x86 language is a fixed constant. -- Copyright 2024 Olcott "Talent hits a target no one else can hit; Genius hits a target no one else can see." Arthur Schopenhauer