Path: utzoo!dciem!nrcaer!scs!spl1!laidbak!att!pacbell!lll-tis!helios.ee.lbl.gov!pasteur!ucbvax!bloom-beacon!AI.AI.MIT.EDU!NICK From: NICK@AI.AI.MIT.EDU (Nick Papadakis) Newsgroups: comp.ai.digest Subject: [ayl%hutds.hut.fi%FINGATE.BITNET@MITVMA.MIT.EDU: the human mind as a logical system] Message-ID: <19880602045141.3.NICK@JONES.AI.MIT.EDU> Date: 2 Jun 88 04:51:00 GMT Article-I.D.: JONES.19880602045141.3.NICK Sender: daemon@bloom-beacon.MIT.EDU Organization: The Internet Lines: 27 Approved: ailist@ai.ai.mit.edu Date: Fri, 27 May 88 21:04 EDT From: Antti YlikoskiTo: AIList@AI.AI.MIT.EDU Subject: the human mind as a logical system cc: ayl@hutds.hut.fi It would seem that the human mind is very fault-tolerant with respect to locigal oddities. Example: a human being can be a queer reasoner in the sense of Smullyan. I recall that a queer reasoner believes a proposition p (Bp) and simultaneously believes he/she doesn's believe p (B - (Bp)), the minus sign denoting logical negation. Let John be a true believer of some obscure faith. Say the Tur religion by Edgar R. Burroughs in his Tarzan books. Let p be the proposition "Tur exists". Let John lament his lack of faith to a Tur priest. Then John believes in Tur (Bp) but believes he doesn't believe in Tur (B - (Bp)). Andy Ylikoski