Deutsch English Français Italiano |
<1ac0740e95f9e4a23b987a71b17acb22ac9980fc@i2pn2.org> View for Bookmarking (what is this?) Look up another Usenet article |
Path: ...!weretis.net!feeder9.news.weretis.net!i2pn.org!i2pn2.org!.POSTED!not-for-mail From: Richard Damon <richard@damon-family.org> Newsgroups: comp.theory Subject: Re: Why Tarski is wrong --- Montague, Davidson and Knowledge Ontology providing situational context. Date: Fri, 21 Mar 2025 19:48:56 -0400 Organization: i2pn2 (i2pn.org) Message-ID: <1ac0740e95f9e4a23b987a71b17acb22ac9980fc@i2pn2.org> References: <vr1shq$1qopn$1@dont-email.me> <7f68c434c15abfc9d4b645992344f0e851f031a3@i2pn2.org> <vr4t3e$bkso$5@dont-email.me> <vr50bg$ed3o$5@dont-email.me> <vr5abg$m5ov$6@dont-email.me> <8ea8c8f1c661d0f2eef855af9b4c171d4f574826@i2pn2.org> <vr6po4$1udpn$7@dont-email.me> <4965dcbb84fc29c9ba9d3cea39b59a8608bfeb66@i2pn2.org> <vr7v51$2u81k$3@dont-email.me> <7db5f56a38a6b6eda2b63acc2568f5dedcc55efd@i2pn2.org> <vr9fp6$bv13$5@dont-email.me> <vrbrkd$2ii4j$1@dont-email.me> <vrbss5$2j07c$1@dont-email.me> <2dd0fa97e2387ba4bca36b40ca16925933b35d9a@i2pn2.org> <vrfe7q$1oabl$1@dont-email.me> <0e92642bf4519e50ba48d51b52d17749c6e19664@i2pn2.org> <vri3va$3egq$1@dont-email.me> <9495b0ea31b3c2559cf9515bfabe071d48cc9d39@i2pn2.org> <vrinjq$kefg$2@dont-email.me> <vrj702$14v65$1@dont-email.me> <vrjboo$17u8e$2@dont-email.me> <87h63mqizb.fsf@nosuchdomain.example.com> <vrkhmb$29m93$2@dont-email.me> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Injection-Date: Fri, 21 Mar 2025 23:48:56 -0000 (UTC) Injection-Info: i2pn2.org; logging-data="1199593"; mail-complaints-to="usenet@i2pn2.org"; posting-account="diqKR1lalukngNWEqoq9/uFtbkm5U+w3w6FQ0yesrXg"; User-Agent: Mozilla Thunderbird X-Spam-Checker-Version: SpamAssassin 4.0.0 Content-Language: en-US In-Reply-To: <vrkhmb$29m93$2@dont-email.me> Bytes: 3027 Lines: 29 On 3/21/25 4:20 PM, Richard Heathfield wrote: > On 21/03/2025 19:30, Keith Thompson wrote: >> My understanding is that Gödel proved that there are statements >> that are true but not provable. > > Yes. Incompleteness. > >> It's still not possible for both >> X and not-X to be provable. If proofs exist for both, at least >> one of the proofs must be flawed. > > I'd be interested to see a proof of that conjecture. > It comes from the definition of consistency. If something is provable, then it must be true, as the proof shows the path from the fundamental truths the the stateemnt, establishing its truth. If both x and not-x are probable then both x and not-x are true, which is the definition of a contradiction. Most of these proofs start with the requirement that the system we are starting with in non-contradictory, i.e, there are no contradictions probable in it. There are some more outlying logic systems, that due to built in weakness of their logic, do not support the principle of explosion, and thus can be defined to allow limited contradictions to exist in them, but these are on the fringe and not commonly used.