Path: csiph.com!aioe.org!.POSTED.htfZkTfFR/p6/9lTV866gA.user.gioia.aioe.org!not-for-mail From: Louis Valence Newsgroups: comp.programming Subject: Re: Everything I say is false. Date: Wed, 30 Oct 2019 16:26:47 -0300 Organization: Aioe.org NNTP Server Lines: 67 Message-ID: <86k18mc9vs.fsf@example.com> References: <86v9svmn9m.fsf@example.com> <865zkrcrvh.fsf@example.com> <0ed80226-a4b8-4fcd-b84b-bc1418608ddb@googlegroups.com> NNTP-Posting-Host: htfZkTfFR/p6/9lTV866gA.user.gioia.aioe.org Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Complaints-To: abuse@aioe.org Cancel-Lock: sha1:gxMr05IPuZKjOajlXaB6kLJr9G0= X-Notice: Filtered by postfilter v. 0.9.2 Xref: csiph.com comp.programming:10274 Öö Tiib writes: > On Monday, 14 October 2019 17:40:38 UTC+3, Louis Valence wrote: >> Richard Heathfield writes: >> >> > On 11/10/2019 14:20, Louis Valence wrote: >> >> Richard Heathfield writes: >> >> >> >>> On 09/10/2019 20:10, mikegonta@gmail.com wrote: >> >>>> Everything I say is false. >> >>> >> >>> That's not true. >> >>> >> >>> But *some* things you say are false, and the above is an example. >> >> >> >> Fun with logic. :-) >> > >> > Indeed. Here's an age-worn and very familiar paradox (bear with me here): >> > >> > Side A: >> > +------------------------------+ >> > + The sentence on the other + >> > + side of this card is true. + >> > +------------------------------+ >> > >> > Side B: >> > +------------------------------+ >> > + The sentence on the other + >> > + side of this card is false. + >> > +------------------------------+ >> > >> > If you now turn the card on its side and inspect the edge with a >> > powerful microscope, you will see the following words, carved in >> > carbon atoms individually arranged by people with far too much time >> > and equipment on their hands: >> > >> > +------------------------------+ >> > + Everything written on Side A + >> > + and Side B is bloody stupid. + >> > +------------------------------+ >> > >> > Paradox resolved! >> >> I'm slow, so bear with me. Either A is true or false. Assume it's >> true. Then B must be true. But if B is true, A cannot be true. Okay. >> Then assume A is false. Then B must be false. If B is false, then A >> must be true. Contradiction. So we can't satisfy both statements >> together with either truth-value. Alright. I see it. >> >> Here's perhaps my favorite version! >> >> --8<---------------cut here---------------start------------->8--- >> What is the probability that you'll randomly answer this question and >> get it right? Check all answers that apply. >> >> (a) 25% (b) 50% (c) 60% (d) 25% >> --8<---------------cut here---------------end--------------->8--- >> >> I think this one is really interesting. > > Since there are 16 different ways to check these > answers randomly and only checking none is correct > the probability is 6.25%. Cool. You didn't assume you should check only a single answer. You're saying the question should be left blank. I think you're correct. It is not, then, another case of Russell's Paradox. Well done!