From cowan Sat Mar 6 22:53:17 2010 Subject: Re: tech:logic matters To: lojban@cuvmb.cc.columbia.edu (Lojban List) From: cowan Date: Tue, 16 Jan 1996 13:49:24 -0500 (EST) In-Reply-To: <199601141441.JAA00747@locke.ccil.org> from "ucleaar" at Jan 14, 96 02:13:37 pm X-Mailer: ELM [version 2.4 PL24] Content-Type: text Status: OR X-Mozilla-Status: 0011 Content-Length: 1277 X-From-Space-Date: Tue Jan 16 13:49:24 1996 X-From-Space-Address: cowan Message-ID: la .and. cusku di'e > This is maybe the source of the problem. I, and evidently most > others among us, but not you, have believed that "all men are mortal" > (and its jbobau equivalents, {ro prenu}, {ro da poi kea prenu}) > means "Ax if x is a man then x is mortal", whereas for you it > means something like "In a subworld containing only men, everything > is mortal", "restricting our attention to individuals that are men, > every individual is mortal". > > In summary: The real dispute between you & the rest of lojbania > is not about whether "(Ax Fx) -> (Ex Fx)" is true (I am willing to > accept that it is). Rather, the dispute is about whether lojban > quantification is restricted or unrestricted: you say it is > restricted, and the rest of lojbania says it is unrestricted. I stand with pc here: the whole purpose of "da poi ... ku'o" constructs is to represent the restricted quantification of Aristotelian logical forms. The fact that "all men are mortal" is equivalent to "for all X, if X is a man then X is mortal" is a theorem, not a mere convention of rewriting. My recent proposal that "ro prenu" means "ro da poi prenu" (and not "ro lo prenu") restores the original pre-Lojban situation. -- John Cowan cowan@ccil.org e'osai ko sarji la lojban.