From phma@webjockey.net Sat May 18 12:03:15 2002 Return-Path: X-Sender: phma@ixazon.dynip.com X-Apparently-To: lojban@yahoogroups.com Received: (EGP: mail-8_0_3_2); 18 May 2002 19:03:15 -0000 Received: (qmail 94995 invoked from network); 18 May 2002 19:03:15 -0000 Received: from unknown (66.218.66.218) by m11.grp.scd.yahoo.com with QMQP; 18 May 2002 19:03:15 -0000 Received: from unknown (HELO neofelis.ixazon.lan) (208.150.110.21) by mta3.grp.scd.yahoo.com with SMTP; 18 May 2002 19:03:14 -0000 Received: by neofelis.ixazon.lan (Postfix, from userid 500) id 367C63C48C; Sat, 18 May 2002 15:03:13 -0400 (EDT) Content-Type: text/plain; charset="iso-8859-1" To: lojban@yahoogroups.com Subject: Re: [lojban] zgamuvjga Date: Sat, 18 May 2002 15:03:08 -0400 X-Mailer: KMail [version 1.2] References: <200205161736.NAA11895@mail.reutershealth.com> In-Reply-To: <200205161736.NAA11895@mail.reutershealth.com> X-Spamtrap: fesmri@ixazon.dynip.com MIME-Version: 1.0 Message-Id: <0205181503080X.02013@neofelis> Content-Transfer-Encoding: 8bit Sender: phma@ixazon.dynip.com From: Pierre Abbat X-Yahoo-Group-Post: member; u=92712300 On Thursday 16 May 2002 13:36, John Cowan wrote: > I don't understand what x3 has to do with it, frankly. I can talk about > the parallax of an object on the opposite wall from one side of a room > vs. the other side, without postulating an observer who actually moves > across the room. > > Furthermore, an important case of parallax is the parallax between a single > observer's left and right eyes, which is the basis of depth perception, > and obviously does not involve any sort of motion. > > So I propose: x1 is the parallax of x2 at observation point x3 relative to > observation point x4. But that's just jganu (except that {jganu} has x3 being the line segment). I think that "parallax" entails that there be an observer or observers. phma