Return-Path: LOJBAN%CUVMB.BITNET@vms.dc.LSOFT.COM Received: from SEGATE.SUNET.SE (segate.sunet.se [192.36.125.6]) by xiron.pc.helsinki.fi (8.7.1/8.7.1) with ESMTP id PAA15532 for ; Sun, 7 Jan 1996 15:02:21 +0200 Message-Id: <199601071302.PAA15532@xiron.pc.helsinki.fi> Received: from listmail.sunet.se by SEGATE.SUNET.SE (LSMTP for OpenVMS v1.0a) with SMTP id 3A336031 ; Sun, 7 Jan 1996 14:02:21 +0100 Date: Sun, 7 Jan 1996 13:01:28 +0000 Reply-To: ucleaar Sender: Lojban list From: ucleaar Subject: tech:logic matters X-To: lojban@cuvmb.cc.columbia.edu To: Veijo Vilva Content-Length: 1503 Lines: 33 pc: > & > Okay. So {ro da broda} entails {da broda}. But all other uses of {ro} > don't entail existence - {ro da poi kea broda cu brode} and > {ro broda cu brode} entail neither {da broda} nor {da brode}. > One ought to be encouraged, I think, to not use poi clauses with da, > and to instead use logical connectives. > pc: > Well, in fact, _ro da poi broda_ was introduced ages ago exactly to > carry the implication that there are brodas. I'm especially out of my depth here, so forgive my being slow on the uptake. I hope I'm right in thinking that "Ax: F(x) -> G(x)" does not entail "Ex F(x)" (or "Ex G(x)"). [I understand from you that it does entail "Ex: F(x) -> G(x)".] I have thought that {ro da poi kea broda cu brode} and {ro broda cu brode} both give "Ax: broda(x) -> brode(x)" - with neither entailing "Ex broda(x)". I assumed that it is in emulation of nat lang syntax rather than predicate logic that these forms are used in preference to a form with logical connectives (ganai...gi). > The other expressions, _ro broda_ and _ro lo broda_ are, I think, up > for grabs, but Cowan sems to have appropriated all of these distinct > expressions for some other set of distinctions. And I, of course, > think that _ro_ should be treated as uniformly as possible, which > would mean requiring the _ganai _gi_ construction to get the "modern" > interpretation. It would be helpful if you would indicate what logical form corresponds to {ro da poi kea broda} and {ro broda}. coo; mie lao a &