Path: ...!news.misty.com!weretis.net!feeder9.news.weretis.net!i2pn.org!i2pn2.org!.POSTED!not-for-mail From: Richard Damon Newsgroups: comp.theory,sci.logic Subject: Re: DDD correctly emulated by H0 -- Ben agrees that Sipser approved criteria is met Date: Tue, 25 Jun 2024 22:23:00 -0400 Organization: i2pn2 (i2pn.org) Message-ID: References: <87jzidm83f.fsf@bsb.me.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Injection-Date: Wed, 26 Jun 2024 02:23:00 -0000 (UTC) Injection-Info: i2pn2.org; logging-data="1191319"; mail-complaints-to="usenet@i2pn2.org"; posting-account="diqKR1lalukngNWEqoq9/uFtbkm5U+w3w6FQ0yesrXg"; User-Agent: Mozilla Thunderbird In-Reply-To: X-Spam-Checker-Version: SpamAssassin 4.0.0 Content-Language: en-US Bytes: 6775 Lines: 131 On 6/25/24 10:05 PM, olcott wrote: > On 6/25/2024 8:47 PM, Richard Damon wrote: >> On 6/25/24 1:45 PM, olcott wrote: >>> On 6/25/2024 9:46 AM, Alan Mackenzie wrote: >>>> Hi, Ben. >>>> >>>> Ben Bacarisse wrote: >>>>> Alan Mackenzie writes: >>>> >>>>>> In comp.theory olcott wrote: >>>>>>> On 6/25/2024 4:22 AM, joes wrote: >>>>>>>> Am Sat, 22 Jun 2024 13:47:24 -0500 schrieb olcott: >>>>>>>>> On 6/22/2024 1:39 PM, Fred. Zwarts wrote: >>>>>>>>>> Op 21.jun.2024 om 15:21 schreef olcott: >>>> >>>>>>>>> When we stipulate that the only measure of a correct emulation >>>>>>>>> is the >>>>>>>>> semantics of the x86 programming language then we see that when >>>>>>>>> DDD is >>>>>>>>> correctly emulated by H0 that its call to H0(DDD) cannot possibly >>>>>>>>> return. >>>>>>>> Yes. Which is wrong, because H0 should terminate. >>>> >>>>>> [ .... ] >>>> >>>>>>> The call from DDD to H0(DDD) when DDD is correctly emulated >>>>>>> by H0 cannot possibly return. >>>> >>>>>>> Until you acknowledge this is true, this is the >>>>>>> only thing that I am willing to talk to you about. >>>> >>>>>> I think you are talking at cross purposes.  Joes's point is that H0 >>>>>> should terminate because it's a decider.  You're saying that when >>>>>> H0 is >>>>>> "correctly" emulating, it won't terminate.  I don't recall seeing >>>>>> anybody >>>>>> arguing against that. >>>> >>>>>> So you're saying, in effect, H0 is not a decider.  I don't think >>>>>> anybody >>>>>> else would argue against that, either. >>>> >>>>> He's been making exactly the same nonsense argument for years.  It >>>>> became crystal clear a little over three years ago when he made the >>>>> mistake of posting the pseudo-code for H -- a step by step simulator >>>>> that stopped simulating (famously on line 15) when some pattern was >>>>> detected.  He declared false (not halting) to be the correct result >>>>> for >>>>> the halting computation H(H_Hat(), H_Hat()) because of what H(H_Hat(), >>>>> H_Hat()) would do "if line 15 were commented out"! >>>> >>>>> PO does occasionally make it clear what the shell game is. >>>> >>>> I think it's important for (relative) newcomers to the newsgroup to >>>> become aware of this.  Each one of them is trying to help PO improve >>>> his >>>> level of learning.  They will eventually give up, as you and I have >>>> done, recognising (as Mike Terry, in particular, has done) that >>>> enriching PO's intellect is a quite impossible task. >>>> >>>> What's the betting he'll respond to this post with his usual short >>>> sequence of x86 assembly code together with a demand to recognise >>>> something or other as non-terminating? >>>> >>>>> -- >>>>> Ben. >>>> >>> >>> >>>      If simulating halt decider H correctly simulates its input D >>>      until H correctly determines that its simulated D would never >>>      stop running unless aborted then >>> >>>      H can abort its simulation of D and correctly report that D >>>      specifies a non-halting sequence of configurations. >>> >>> >>> On 10/14/2022 7:44 PM, Ben Bacarisse wrote: >>>  > I don't think that is the shell game. PO really /has/ an H >>>  > (it's trivial to do for this one case) that correctly determines >>>  > that P(P) *would* never stop running *unless* aborted. >>>  > >>>  > He knows and accepts that P(P) actually does stop. The >>>  > wrong answer is justified by what would happen if H >>>  > (and hence a different P) where not what they actually are. >>>  > >>> >>> Ben thinks that I tricked professor Sipser into agreeing >>> with something that he did not fully understand. >>> >>> *The real issue is that no one here sufficiently understands* >>> *the highlighted portion of the following definition* >>> >>> Computable functions are the formalized analogue of the >>> intuitive notion of algorithms, in the sense that a >>> function is computable if there exists an algorithm >>> that can do the job of the function, i.e. >>> >>> *given an input of the function domain* >>> *it can return the corresponding output* >>> >>> https://en.wikipedia.org/wiki/Computable_function >>> >>> >> >> But only if the function is, in fact, computable. >> >> Since Halting isn't, you can't use that fact. > > If I ask you: What time is it? > and you do not tell me the answer to the question hidden > in my mind "What did you have for dinner?" We cannot say > that you provided the wrong answer when you tell me what > time it is. Because I answered the actual question. Just like the "Halt Decider" needs to answer the "Halt Decider Question" and not answer about POOP. > > When we ask H to tell us whether its actual input halts > H can only answer that P correctly simulated by H will not halt. > H cannot answer the question hidden in your mind. > Then you are just admitting that it can't be a Halt Decider. If it isn't what the definition requires, it just isn't one.