From pycyn@aol.com Mon Oct 01 19:24:55 2001 Return-Path: X-Sender: Pycyn@aol.com X-Apparently-To: lojban@yahoogroups.com Received: (EGP: mail-7_4_1); 2 Oct 2001 02:23:05 -0000 Received: (qmail 20493 invoked from network); 2 Oct 2001 02:23:05 -0000 Received: from unknown (10.1.10.142) by 10.1.1.221 with QMQP; 2 Oct 2001 02:23:05 -0000 Received: from unknown (HELO imo-r08.mx.aol.com) (152.163.225.104) by mta3 with SMTP; 2 Oct 2001 02:24:54 -0000 Received: from Pycyn@aol.com by imo-r08.mx.aol.com (mail_out_v31_r1.7.) id r.d1.d4d8adb (4406) for ; Mon, 1 Oct 2001 22:24:47 -0400 (EDT) Message-ID: Date: Mon, 1 Oct 2001 22:24:46 EDT Subject: Re: [lojban] Set of answers encore To: lojban@yahoogroups.com MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="part1_d1.d4d8adb.28ea7f6e_boundary" X-Mailer: AOL 6.0 for Windows US sub 10535 From: pycyn@aol.com --part1_d1.d4d8adb.28ea7f6e_boundary Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit In a message dated 10/1/2001 7:17:57 PM Central Daylight Time, jjllambias@hotmail.com writes: > >Why would "le du'u " be different from "le broda"? If 'le' > >always refers to the extension, then doesn't "le du'u " refer > >to the extension of "du'u "? > > Yes, but the extension of {du'u broda} preserves the intension > of {broda}. {le broda} and {le brode}, for broda different than > brode, can refer to the same extension, but {le du'u broda} will > Well, sorta. Suppose that {brode} and {brode} refer to exactly the ame things in fact, "has a heart" and "has a liver," say (I'm sure la pier will tell me this examples is hopelessly out of date and it probably is, but suppose). The {ko'a broda} and {ko'a brode} will be true or fasle together for every referent of {ko'a}. That means that le du'u koa broda} and {le du'u ko'a brode} always have the same truth value, for a given referent of {ko'a}. And so theya re equivalent and interchangeable in any context where only the truth value matters. But there are contexts where the truth value is not all that matters: {mi jinvi...} for example. There you cannot exchange items with the same truth value and be sure to keep the truth value of the whole the same. Why not? The standard answer is that in those contexts (intensional contexts) the referent of the expression {le du'u ko'a broda} is no longer the basic referent, its truth value, but its regular sense -- roughly the rule by which one determines its truth value in a given world. Clearly, looking for a heart (pump in the blood system) is different from looking for a liver (filter in the blood system), so the rules are different and thus the two expressions are no longer interchangeable. The reason for this rule is that, without it, you get absurdities like moving from "Jim believes that 2+2 =4," to "Jim believes that Casaubon showed the Smargdarine Tables were a third century pseudograph" on the grounds that they are both true. The rule slows the errors down quite a bit. It is debatable whether this means that {du'u ko'a broda} has a different extension from {du'u ko'a brode} or whether it means that in some cases it is not the extension but the intension that counts (I find the latter easier to deal with). --part1_d1.d4d8adb.28ea7f6e_boundary Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: 7bit In a message dated 10/1/2001 7:17:57 PM Central Daylight Time, jjllambias@hotmail.com writes:

>Why would "le du'u <bridi>" be different from "le broda"? If 'le'
>always refers to the extension, then doesn't "le du'u <bridi>" refer
>to the extension of "du'u <bridi>"?

Yes, but the extension of {du'u broda} preserves the intension
of {broda}. {le broda} and {le brode}, for broda different than
brode, can refer to the same extension, but {le du'u broda} will
be a different extension than {le du'u brode}.

Well, sorta. Suppose that {brode} and {brode} refer to exactly the ame things in fact, "has a heart" and "has a liver," say (I'm sure la pier will tell me this examples is hopelessly out of date and it probably is, but suppose). The {ko'a broda} and {ko'a brode} will be true or fasle together for every referent of {ko'a}. That means that le du'u koa broda} and {le du'u ko'a brode} always have the same truth value, for a given referent of {ko'a}. And so theya re equivalent and interchangeable in any context where only the truth value matters. But there are contexts where the truth value is not all that matters: {mi jinvi...} for example. There you cannot exchange items with the same truth value and be sure to keep the truth value of the whole the same. Why not? The standard answer is that in those contexts (intensional contexts) the referent of the expression {le du'u ko'a broda} is no longer the basic referent, its truth value, but its regular sense -- roughly the rule by which one determines its truth value in a given world. Clearly, looking for a heart (pump in the blood system) is different from looking for a liver (filter in the blood system), so the rules are different and thus the two expressions are no longer interchangeable. The reason for this rule is that, without it, you get absurdities like moving from "Jim believes that 2+2 =4," to "Jim believes that Casaubon showed the Smargdarine Tables were a third century pseudograph" on the grounds that they are both true. The rule slows the errors down quite a bit. It is debatable whether this means that {du'u ko'a broda} has a different extension from {du'u ko'a brode} or whether it means that in some cases it is not the extension but the intension that counts (I find the latter easier to deal with).

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