Path: ...!news.misty.com!weretis.net!feeder9.news.weretis.net!news.quux.org!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: Why Peter Olcott is both right and wrong Date: Thu, 15 May 2025 13:23:43 +0100 Organization: A noiseless patient Spider Lines: 24 Message-ID: <877c2i2hbk.fsf@bsb.me.uk> References: <5PfVP.200711$RD41.12367@fx12.ams4> MIME-Version: 1.0 Content-Type: text/plain Injection-Date: Thu, 15 May 2025 14:23:45 +0200 (CEST) Injection-Info: dont-email.me; posting-host="6bc9738fb3a1ffe22fecbf1eebc7f9a0"; logging-data="3287489"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX1+If5W/cFAcXQDPahLLrbgXBhUuLXcioo8=" User-Agent: Gnus/5.13 (Gnus v5.13) Cancel-Lock: sha1:ulRbjbXfK8wHH9gCekdJ4QW4Qng= sha1:q/2SzGfYo00jsk02FyqN7SDqxvI= X-BSB-Auth: 1.dec8a15784fae970e3da.20250515132343BST.877c2i2hbk.fsf@bsb.me.uk Bytes: 1848 Mr Flibble writes: > the truth is pathlogical input is undecidable: No input[1] is undecidable. > that part Turing et al got right. Turing never said that there are undecidable inputs[2]. Maybe "truth", "pathological", "input" and "undecidable" have special Flibble meanings. I'm willing to accept that "the" and "is" have the usual semantics. [1] By input I mean an instance of the halting problem -- a string of symbols representing (a) an encoded TM (a number is Turing's paper) and (b) the initial tape contents. [2] In the original paper, he never uses the words "input" or "decidable". Instead, he uses other words, but nowhere is there any remark that is even close to meaning what you say. -- Ben.