Path: ...!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!eternal-september.org!.POSTED!not-for-mail From: dbush Newsgroups: comp.theory Subject: Re: What it would take... People to address my points with reasoning instead of rhetoric -- RP Date: Wed, 14 May 2025 16:54:01 -0400 Organization: A noiseless patient Spider Lines: 163 Message-ID: <1002vt8$2mbr6$4@dont-email.me> References: <87v7q5n3sc.fsf@bsb.me.uk> <87plgdmldp.fsf@bsb.me.uk>

<1000ce4$21dtc$3@dont-email.me> <1000q52$24gr3$2@dont-email.me> <1000qss$24jh0$2@dont-email.me> <1000rfv$24gr3$6@dont-email.me> <1000s0e$24sr2$1@dont-email.me> <1000s6d$24gr3$8@dont-email.me> <1000t1a$24sr2$4@dont-email.me> <1000t8e$24gr3$11@dont-email.me> <1000vs5$29e7u$1@dont-email.me> <100101g$24gr3$14@dont-email.me> <10011b6$29e7u$4@dont-email.me> <10012le$24gr3$17@dont-email.me> <1001370$2a1j4$1@dont-email.me> <10013q1$24gr3$20@dont-email.me> <10016i2$2aias$2@dont-email.me> <1001t7e$2f9oj$1@dont-email.me> <1002e7b$2i4bk$16@dont-email.me> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Injection-Date: Wed, 14 May 2025 22:54:00 +0200 (CEST) Injection-Info: dont-email.me; posting-host="794812149fd3df87a1483ec84874242e"; logging-data="2830182"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX1/Tse1QL5lOO5JVIePdzv/g" User-Agent: Mozilla Thunderbird Cancel-Lock: sha1:i3BpRIEILhU4Q0zfeJ2OrZhNMGI= In-Reply-To: <1002e7b$2i4bk$16@dont-email.me> Content-Language: en-US Bytes: 8991 On 5/14/2025 11:52 AM, olcott wrote: > On 5/14/2025 6:02 AM, Fred. Zwarts wrote: >> Op 14.mei.2025 om 06:35 schreef olcott: >>> On 5/13/2025 10:48 PM, dbush wrote: >>>> On 5/13/2025 11:38 PM, olcott wrote: >>>>> On 5/13/2025 10:28 PM, dbush wrote: >>>>>> On 5/13/2025 11:06 PM, olcott wrote: >>>>>>> On 5/13/2025 9:44 PM, dbush wrote: >>>>>>>> On 5/13/2025 10:41 PM, olcott wrote: >>>>>>>>> On 5/13/2025 8:56 PM, dbush wrote: >>>>>>>>>> On 5/13/2025 9:52 PM, olcott wrote: >>>>>>>>>>> On 5/13/2025 8:38 PM, dbush wrote: >>>>>>>>>>>> On 5/13/2025 9:35 PM, olcott wrote: >>>>>>>>>>>>> On 5/13/2025 8:26 PM, dbush wrote: >>>>>>>>>>>>>> On 5/13/2025 9:16 PM, olcott wrote: >>>>>>>>>>>>>>> On 5/13/2025 8:03 PM, dbush wrote: >>>>>>>>>>>>>>>> Nope. Russell's Paradox was derived from the base >>>>>>>>>>>>>>>> axioms of naive set theory, proving the whole system was >>>>>>>>>>>>>>>> inconsistent. >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> In contrast, there is nothing in existing computation >>>>>>>>>>>>>>>> theory that requires that a halt decider exists. >>>>>>>>>>>>>> >>>>>>>>>>>>>> I see you made no attempt to refute the above statement. >>>>>>>>>>>>>> Unless you can show from the axioms of computation theory >>>>>>>>>>>>>> that the following requirements can be met, your argument >>>>>>>>>>>>>> has no basis: >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> 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 >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>> A halt decider doesn't exist >>>>>>>>>>>>>>>>> for the same reason that the set of all sets >>>>>>>>>>>>>>>>> that do not contain themselves does not exist. >>>>>>>>>>>>>>>>> *As defined both were simply wrong-headed ideas* >>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>> There's nothing wrong-headed about wanting to know if >>>>>>>>>>>>>>>> any arbitrary algorithm X with input Y will halt when >>>>>>>>>>>>>>>> executed directly. >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Yes there is. I have proven this countless times. >>>>>>>>>>>>>> >>>>>>>>>>>>>> That requirements are impossible to satisfy doesn't make >>>>>>>>>>>>>> them wrong. It just makes them impossible to satisfy, >>>>>>>>>>>>>> which is a perfectly reasonable conclusion. >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> It did with Russell's Paradox. >>>>>>>>>>>>> ZFC rejected the whole foundation upon which >>>>>>>>>>>>> RP was built. >>>>>>>>>>>>> >>>>>>>>>>>>> ZFC did not solve some other Russell's Paradox >>>>>>>>>>>>> it rejected the whole idea of RP as nonsense. >>>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> Unless you can show from the axioms of computation theory >>>>>>>>>>>> that the following requirements can be met, your argument >>>>>>>>>>>> has no basis: >>>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> Alternatively I can do what ZFC did and over-rule >>>>>>>>>>> the whole foundation upon which the HP proofs are build. >>>>>>>>>> >>>>>>>>>> You mean the assumption that the following requirements (which >>>>>>>>>> are *not* part of the axioms of computation theory) can be >>>>>>>>>> satisfied? The assumption that Linz and other proved was false >>>>>>>>>> and that you *explicitly* agreed with? >>>>>>>>>> >>>>>>>>> >>>>>>>>> The conventional halting problem proofs have your >>>>>>>>> requirements as its foundation. >>>>>>>>> >>>>>>>> >>>>>>>> They have the *assumption* that the requirements can be met, and >>>>>>>> via proof by contradiction show the assumption to be false. >>>>>>>> >>>>>>>> And the fact that the requirements can't be met is fine, just >>>>>>>> like the the fact that these requirements can't be met is fine: >>>>>>>> >>>>>>>> A mythic number is a number N such that N > 5 and N < 2. >>>>>>> >>>>>>> We can also say that no computation can compute >>>>>>> the square root of a dead rabbit. In none of these >>>>>>> cases is computation actually limited. >>>>>>> >>>>>>> We could equally say that no whale can give >>>>>>> birth to a pigeon. This places no actual limit >>>>>>> on the behavior of whales. Whales were never >>>>>>> meant to give birth to pigeons. >>>>>>> >>>>>> >>>>>> And as was said before: >>>>>> >>>>>> On 5/5/2025 5:39 PM, olcott wrote: >>>>>> > On 5/5/2025 4:31 PM, dbush wrote: >>>>>> >> Strawman. The square root of a dead rabbit does not exist, >>>>>> but the >>>>>> >> question of whether any arbitrary algorithm X with input Y >>>>>> halts when >>>>>> >> executed directly has a correct answer in all cases. >>>>>> >> >>>>>> > >>>>>> > It has a correct answer that cannot ever be computed >>>>>> >>>>>> This qualifies as both a non-rebuttal and your confirmation you >>>>>> agree that Linz and others are correct that no algorithm exists >>>>>> that satisfies the below requirements: >>>>>> >>>>>> >>>>>> 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 >>>>>> >>>>> >>>>> It is true that a TM either halts or does not halt. >>>>> >>>>> None-the-less the above requirements simply ignore >>>>> that some inputs specify behavior that differs >>>>> from the behavior of their direct execution. >>>> >>>> What you think the input specifies is irrelevant. >>> >>> What it actually specifies rules the computation. >>> >> And the input includes the code to abort, so that should be included >> in the computation of the mapping. If it doesn't use the full >> specification, the mapping is incorrect > > > 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 > And *yet again* you lie by implying Sipser agrees with your interpretation of the above when definitive proof has been repeatedly provided that he did not: On Monday, March 6, 2023 at 2:41:27 PM UTC-5, Ben Bacarisse wrote: > I exchanged emails with him about this. He does not agree with anything > substantive that PO has written. I won't quote him, as I don't have > permission, but he was, let's say... forthright, in his reply to me. Your dishonesty knows no bounds.