Path: ...!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!eternal-september.org!.POSTED!not-for-mail From: Ben Bacarisse Newsgroups: comp.theory Subject: Re: Analysis of =?utf-8?Q?Flibble=E2=80=99s?= Latest: Detecting vs. Simulating Infinite Recursion ZFC Date: Sun, 25 May 2025 01:42:23 +0100 Organization: A noiseless patient Spider Lines: 75 Message-ID: <87h619wmfk.fsf@bsb.me.uk> References: <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$1@dont-email.me> <87msb2x39x.fsf@bsb.me.uk> <100rbkf$g939$1@dont-email.me> MIME-Version: 1.0 Content-Type: text/plain Injection-Date: Sun, 25 May 2025 02:42:45 +0200 (CEST) Injection-Info: dont-email.me; posting-host="7919a1321412edc99145382bd3827ed5"; logging-data="1075951"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX1/FS+0Yv4sPjQqwns81gEKKB/LxZHy9lY8=" User-Agent: Gnus/5.13 (Gnus v5.13) Cancel-Lock: sha1:tGaW8spspzxvtc0AyvJ++uH8pL4= sha1:FegXpG744XDJrvwKz5opfjU8hy0= X-BSB-Auth: 1.93a451ed924858c8c1c1.20250525014223BST.87h619wmfk.fsf@bsb.me.uk Bytes: 5493 Mike Terry writes: > On 24/05/2025 01:26, Ben Bacarisse wrote: >> Mike Terry writes: >> >>> On 23/05/2025 19:37, Keith Thompson wrote: >>>> Ben Bacarisse writes: >>>>> Mike Terry writes: >>>> [...] >>>>> And the big picture is that this can be done because false is the >>>>> correct halting decision for some halting computations. He has said >>>>> this explicitly (as I have posted before) but he has also explained it >>>>> in words: >>>>> >>>>> | When-so-ever a halt decider correctly determines that its input would >>>>> | never halt unless forced to halt by this halt decider this halt >>>>> | decider has made a correct not-halting determination. >>>> Hmm. I don't read that the way you do. Did I miss something? >>>> It assumes that the input is a non-halting computation ("its input >>>> would never halt") and asserts that, in certain circumstances, >>>> his mythical halt decider correctly determines that the input >>>> is non-halting. >>>> When his mythical halt decider correctly determines that its input >>>> doesn't halt, it has made a correct non-halting determination. >>>> It's just a tautology. >>> >>> You're reading it the way most people would, and in the way I said Sipser >>> would be interpreting the oft-quoted "Sipser quote". I don't think you've >>> missed anything particularly. >> Maybe it makes less sense out of the context it was posted in. This was >> when he was being less obtuse. The computation in question only halts >> because it is halted by the decider on which it is built. It is a >> halting computation, but according to PO it can reported as not halting >> because of what would happen if it were not halted by the decider from >> which it is derived. > > "The computation in question only halts because it is halted by the > decider on which it is built." > > That is presumably you speaking in PO's voice, but my first reading > was as you saying it! It was paraphrase. He has evolved (deliberately) from being very clear: false is correct for some halting computations; the set of halting computation is expanded to include some others; right though to the wording that he managed to trick Sipser with. The intermediate stages involved turns of phrase like "some computations only halt because the simulator halts them" and "it would not halt if line 15 were commented out" and so on. But the basic plan has been the same for years: some halting computations can be classed as non-halting because they halt for a reason he considers special -- a closely related but different computation would not halt. If PO were a normal person, the key would be to go back and forth getting answers to direct questions that would illuminate what he thinks. But cranks always duck and dive when asked direct questions because they know that must avoid being clear. I have dozens of notes of direct questions being evaded, time and time again. The only game (for me) is to try to get a crank to actually say what they mean as clearly as possible. That is, after all, what a proper exchange of view should be based on. .... > As ever, pointing it out to PO, however explicitly and clearly, has no > effect on what PO believes. Right, but it is possible to try to get as clear and concise an expression of what he believes. There's no point in trying to change his mind, but his nonsense can then be laid bare for all to see. At that point, I would want to just repeat it back (every time he posts) with an brief explanation that it's wrong rather than try to educate PO. -- Ben.