From a.rosta@dtn.ntl.com Fri Apr 20 10:38:04 2001 Return-Path: X-Sender: a.rosta@dtn.ntl.com X-Apparently-To: lojban@yahoogroups.com Received: (EGP: mail-7_1_2); 20 Apr 2001 17:38:03 -0000 Received: (qmail 19311 invoked from network); 20 Apr 2001 17:38:02 -0000 Received: from unknown (10.1.10.27) by l10.egroups.com with QMQP; 20 Apr 2001 17:38:02 -0000 Received: from unknown (HELO mta05-svc.ntlworld.com) (62.253.162.45) by mta2 with SMTP; 20 Apr 2001 17:38:02 -0000 Received: from andrew ([62.252.12.248]) by mta01-svc.ntlworld.com (InterMail vM.4.01.02.27 201-229-119-110) with SMTP id <20010420154815.NVJP283.mta01-svc.ntlworld.com@andrew> for ; Fri, 20 Apr 2001 16:48:15 +0100 To: Subject: RE: [lojban] RE:not only Date: Fri, 20 Apr 2001 16:47:20 +0100 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook IMO, Build 9.0.2416 (9.0.2910.0) Importance: Normal In-Reply-To: <4.3.2.7.2.20010419182524.00bf3eb0@127.0.0.1> X-MimeOLE: Produced By Microsoft MimeOLE V5.00.2615.200 From: "And Rosta" I have to say, contra pc but with apparently everyone else, I judge "In the animal kingdom, only spiders have exactly nine legs" to be false. (OK, I admit I find it hard to distinguish falsity from true-but-implying-false-with-maximal-strength, but the way to settle this would be to find a true example that doesn't imply the contrary, and noone's come up with such an example.) Hence "Only S are P" cannot be an exact equivalent of "All P are S", contrary to the position pc takes and I took for many years until now. Instead, "Only S are P" should be treated as equivalent to A. "S are P and nothing but S are P" or B. "S are P and all P are S". OTOH, in practise, "All P are S" would serve perfectly well to communicate "Only S are P", so it seems to me that the logically fastidious among us could happily make do with simply abjuring po'o. --And.