NICK@AI.AI.MIT.EDU (Nick Papadakis) (06/02/88)
Date: Fri, 27 May 88 21:04 EDT From: Antti Ylikoski <ayl%hutds.hut.fi%FINGATE.BITNET@MITVMA.MIT.EDU> To: 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