Path: ...!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!eternal-september.org!.POSTED!not-for-mail From: "Fred. Zwarts" Newsgroups: comp.theory Subject: =?UTF-8?Q?Re=3A_Analysis_of_Flibble=E2=80=99s_Latest=3A_Detecting_v?= =?UTF-8?Q?s=2E_Simulating_Infinite_Recursion_ZFC?= Date: Sun, 25 May 2025 17:25:07 +0200 Organization: A noiseless patient Spider Lines: 133 Message-ID: <100vcol$1e53p$3@dont-email.me> References: <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$1@dont-email.me> <87a573xz0s.fsf@bsb.me.uk> <875xhrtbpr.fsf@nosuchdomain.example.com> <100r2mb$b2b1$1@dont-email.me> <100r4oq$b650$1@dont-email.me> <100r5bf$b5vm$4@dont-email.me> <100r5hn$b650$2@dont-email.me> <100r648$bhcu$1@dont-email.me> <100r68v$b650$3@dont-email.me> <100sn6a$p071$1@dont-email.me> <100snl3$nvac$1@dont-email.me> <100sr6o$ppn2$3@dont-email.me> <100uqcg$1anld$1@dont-email.me> <100v972$1d5lg$4@dont-email.me> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Injection-Date: Sun, 25 May 2025 17:25:10 +0200 (CEST) Injection-Info: dont-email.me; posting-host="59d5741c0b711edff35e33d70aad8f77"; logging-data="1512569"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX183VKefL6+YhtWoUFtaztUm" User-Agent: Mozilla Thunderbird Cancel-Lock: sha1:JF45ctYRZviJZ1aeCmr0HzC14ck= In-Reply-To: <100v972$1d5lg$4@dont-email.me> Content-Language: nl, en-GB Bytes: 7946 Op 25.mei.2025 om 16:24 schreef olcott: > On 5/25/2025 5:11 AM, Mikko wrote: >> On 2025-05-24 16:13:12 +0000, olcott said: >> >>> On 5/24/2025 10:12 AM, dbush wrote: >>>> On 5/24/2025 11:04 AM, olcott wrote: >>>>> On 5/23/2025 8:09 PM, dbush wrote: >>>>>> On 5/23/2025 9:07 PM, olcott wrote: >>>>>>> On 5/23/2025 7:57 PM, dbush wrote: >>>>>>>> On 5/23/2025 8:54 PM, olcott wrote: >>>>>>>>> On 5/23/2025 7:44 PM, dbush wrote: >>>>>>>>>> On 5/23/2025 8:08 PM, Mike Terry wrote: >>>>>>>>>>> I suppose Ben quoted PO saying this, because PO /uses/ it to >>>>>>>>>>> justify that a particular /halting/ computation will never >>>>>>>>>>> halt, PO's HHH simulates DDD (which halts) but before DDD >>>>>>>>>>> halts it spots a pattern in the simulation, and announces >>>>>>>>>>> non- halting. "Eh?" I hear you say! PO claims HHH has >>>>>>>>>>> "correctly determined that DDD would never halt" and so is >>>>>>>>>>> correct to decide non- halting.  His "proof" that it is right >>>>>>>>>>> to decide non-halting is his "when-so- ever.." quote, which >>>>>>>>>>> broadly matches the Sipser quote. >>>>>>>>>>> >>>>>>>>>>> So the problem is not so much the "when-so-ever.." words >>>>>>>>>>> themselves [or the words of Sipser's quote], but >>>>>>>>>>> understanding how PO is so thoroughly misinterpreting/ >>>>>>>>>>> misapplying them.  How can PO believe HHH has "correctly >>>>>>>>>>> determined the DDD will never halt" when DDD demonstrably halts? >>>>>>>>>> >>>>>>>>>> PO is working in a different model than the rest of us, though >>>>>>>>>> he doesn't seem to understand that. >>>>>>>>>> >>>>>>>>>> To him, when function H is deciding on something, the >>>>>>>>>> implementation of H is allowed to vary.  This results in >>>>>>>>>> functions that call H to vary as a result.  To him, "DDD" is >>>>>>>>>> the same computation *regardless of the implementation of >>>>>>>>>> HHH*, in cases where HHH is simulating DDD. >>>>>>>>>> >>>>>>>>>> This is essentially the mapping he's operating with: >>>>>>>>>> >>>>>>>>>> ----------------- >>>>>>>>>> For a function X with input Y and a function H which simulates X: >>>>>>>>>> POH(H,X,Y)==1 if and only if there exists an implementation of >>>>>>>>>> H that can simulate X(Y) to completion >>>>>>>>>> POH(H,X,Y)==0 if and only if there does not exist an >>>>>>>>>> implementation of H that can simulate X(Y) to completion >>>>>>>>>> ---------------- >>>>>>>>>> >>>>>>>>>> And a "decider" in his case maps the following subset: >>>>>>>>>> >>>>>>>>>> ---------------- >>>>>>>>>> Hx is a PO-halt decider if and only if Hx(X,Y) == POH(Hx,X,Y) >>>>>>>>>> ---------------- >>>>>>>>>> >>>>>>>>>> So given his rules, HHH1(DDD) is deciding on a algorithm while >>>>>>>>>> HHH(DDD) is deciding on a C function whose subfunctions vary. >>>>>>>>>> >>>>>>>>>> This of course has nothing to do with the halting problem but >>>>>>>>>> he doesn't get this.  After having spent 22 years on this, >>>>>>>>>> he'll come up with any crazy justification to avoid admitting >>>>>>>>>> to himself that he misunderstood the problem all this time. >>>>>>>>>> He once said (and I don't recall the exact wording) that "the >>>>>>>>>> directly executed D doesn't halt even though it appears to". >>>>>>>>> >>>>>>>>> The problem is that people here are too stupid >>>>>>>>> to notice that HHH cannot report on the behavior >>>>>>>>> of its caller. >>>>>>>>> >>>>>>>>> int min() >>>>>>>>> { >>>>>>>>>    DD(); // HHH cannot report on the behavior of its caller. >>>>>>>>> } >>>>>>>>> >>>>>>>> >>>>>>>> What about this? >>>>>>>> >>>>>>> >>>>>>> If you can't stay exactly on topic I am going to ignore >>>>>>> everything that you say. >>>>>>> >>>>>>> HHH cannot report on the behavior of its caller AKA the >>>>>>> direct execution of DD(). >>>>>>> >>>>>> >>>>>> >>>>>> In other words, you again agree with Linz and others that no H >>>>>> exists that can perform the following mapping: >>>>>> >>>>>> >>>>>> Given any algorithm (i.e. a fixed immutable sequence of >>>>>> instructions) X described as with input Y: >>>>>> >>>>>> A solution to the halting problem is an algorithm H that computes >>>>>> the following mapping: >>>>>> >>>>>> (,Y) maps to 1 if and only if X(Y) halts when executed directly >>>>>> (,Y) maps to 0 if and only if X(Y) does not halt when executed >>>>>> directly >>>>>> >>>>> >>>>> int main() >>>>> { >>>>>    DD(); // The HHH called by DD cannot report on the behavior >>>>> }       // of its caller. Is this OVER-YOUR-HEAD ? >>>>> >>>> >>>> >>>> Which means that no HHH exists that meets the below requirements, as >>>> Linz and others proved and as you have *explicitly* agreed is correct: >>> >>> You are a damned liar when you say that I said >>> that HHH must report on the behavior of its caller. >> >> It is a sin to lie about another persons words. >> >>> No HHH can report on the behavior of its caller >>> for the same reason that no function can report >>> on the value of the square-root of a dead cat. >> >> False. The reason is not the same. No function can report on the value of >> the square root of a dead cat because a desd cat has no square root. But >> eevery caller of HHH has some behaviour that includes calling HHH. >> > > How the Hell can a C function even see its caller? > HHH is given the pointer to its caller DDD. So, it has access to the code of its caller and all functions used by DDD. This code includes the abort code. So the halting behaviour is clearly specified. But HHH is programmed is such a way that it does not see that part of the specification. That bug in HHH does not change the specification in any way. It is childish to claim that something does not exists because you close your eyes and do not see it.