From LOJBAN%CUVMB.BITNET@UBVM.CC.BUFFALO.EDU Fri Jan 12 13:29:15 1996 Received: from vms.dc.lsoft.com (vms.dc.lsoft.com [205.186.43.2]) by locke.ccil.org (8.6.9/8.6.10) with ESMTP id NAA07804 for ; Fri, 12 Jan 1996 13:29:10 -0500 Message-Id: <199601121829.NAA07804@locke.ccil.org> Received: from PEACH.EASE.LSOFT.COM (205.186.43.4) by vms.dc.lsoft.com (LSMTP for OpenVMS v1.0a) with SMTP id 212C1EC0 ; Fri, 12 Jan 1996 12:51:20 -0500 Date: Fri, 12 Jan 1996 08:52:47 -0800 Reply-To: "John E. Clifford" Sender: Lojban list From: "John E. Clifford" Subject: terch:opaque X-To: lojban list To: John Cowan Status: OR X-Mozilla-Status: 0001 Content-Length: 4270 After a couple of weeks with the theoretical logicians, it is a pleasure to get back to practical McCawley. Skipping over what these worlds are, he gives some facts about the way they behave, which we need to take into consideration. First, the worlds for cognitive states (belief and its kin) are different from the those for the volitional states (wanting, intending, etc.), with dream worlds falling somewhere in between. Cognitive worlds are more nearly worlds, including time spans (so other worlds in the temporal order) and other people's belief worlds, indeed, even other possible-world structures. Except as noted overtly, a belief world is assumed to mirror the real world. But it may differ in marked ways, containing entities the real world does not, failing to contain entities the real world does, and, of course, assigning to its entities properties that they do not have in the real world. A belief world may even be inconsistent, a very big situation, then. Finally, belief worlds endure largely unchanged through other changes. The upshot of this for opacity questions is that references to beliefs really are opaque, that we cannot formally take an object in such a context as being also in reality. However, barring overt signs to the contrary, we can make the move pragmatically, for the assumption is, remember, that the belief world mirrors the real unless marked. But the marking may be late ("Oh, I thought you know that he has this weird belief that I have a son, so, when I told you that he believed my son was dropping out, I was just bringing you up to day on his folie") so the formal argument is invalid even for such clear cases as "my son" and proper names (even self references can get skewed). Because belief worlds endure, we can revisit them in the course of a conversation and take into these revisits the anaphora from previous visits, even after a long absence and even if the entry is somewhat different ( that is, not "believe" again but some operator that entails belief). Volitional worlds are among the entries which rely on belief worlds, so that , for example, he can want his daughter to marry my (believed) son. and once that volitional world is established, it can be the basis for further ones, that he wants to name their first child after Nelson Mandela, say. But these volitonal worlds are much smaller than belief worlds and do not endure in the same way. We tend to have to restart the whole volitional scape to get back to them after we have left them. But again they can introduce totally new things (or lose others) relative to even the belief world they start from and anaphora carries over as long as the same (possibly developing) volitional scape is before us, even as the superordinate state markers change. The relation between dream worlds and the real (or even waking belief) world is more complex. One can, for example, dream that one is someone else (real, believed real, or fictional) and even that person is interacting with with one's (real/belief) self: "I dream that I was Brigette Bardot (Okay, so I'm that old!) and was kissing me" (not, note, "kissing myself," which, in this context, would have BB kissing BB). Dream worlds last only as long as the dream and need not contain anything beyond the dream material, but, so long as it is the same dream, we can return to the anaphora from it fairly easily. McCawley deals rather cavalierly (but no probably correctly and certainly simply) with the problem of representation objects. Reminding us that range of variables is the universe of discourse, not reality, he holds that, when we are talking about art, the stock material of art is always in the universe of discourse and, when a particular work is at issue, its content is, of course, in that universe. So, the art work references are not opaque -- although some care is probably needed to distinguish art work objects from the real objects they seem to represent (and, in dramatic art, from the real objects that present the representations). I'm not sure whether any of this solves any Lojbanic problems, but it does give us some useful data to consider in working for solutions. pc>|83