From cowan@ccil.org Mon Feb 18 16:00:35 2002 Return-Path: X-Sender: cowan@mercury.ccil.org X-Apparently-To: lojban@yahoogroups.com Received: (EGP: mail-8_0_2); 19 Feb 2002 00:00:35 -0000 Received: (qmail 19253 invoked from network); 19 Feb 2002 00:00:34 -0000 Received: from unknown (216.115.97.172) by m4.grp.snv.yahoo.com with QMQP; 19 Feb 2002 00:00:34 -0000 Received: from unknown (HELO mercury.ccil.org) (192.190.237.100) by mta2.grp.snv.yahoo.com with SMTP; 19 Feb 2002 00:00:34 -0000 Received: from cowan by mercury.ccil.org with local (Exim 3.12 #1 (Debian)) id 16cxi6-0002pC-00; Mon, 18 Feb 2002 19:00:42 -0500 Subject: Re: [lojban] Re: [jboske] RE: Anything but tautologies In-Reply-To: from Jorge Llambias at "Feb 18, 2002 10:46:05 pm" To: Jorge Llambias Date: Mon, 18 Feb 2002 19:00:42 -0500 (EST) Cc: lojban@yahoogroups.com X-Mailer: ELM [version 2.4ME+ PL66 (25)] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Message-Id: X-eGroups-From: John Cowan From: John Cowan X-Yahoo-Group-Post: member; u=212516 X-Yahoo-Profile: johnwcowan X-Yahoo-Message-Num: 13354 Jorge Llambias scripsit: > xod: x1 is a name and x4 is the function > cowan: x1 is the function and x4 is an expression (a text) > lojbab: x1 is the function and x4 is something like li f(x)=x*2, > which is not very clear what it is because equations > are not numbers. > pc: x1=x4 both are the function, with the proviso that good style > requires to use a more helpful description in x4. > > I much prefer pc's version over any of the others, although even > better for me would be to drop x4 altoghether. I don't see how that can work. Given that x1 is a function (rejecting xod's view), an abstract object, you need some x4 to tell you which function it is. A function is not just any mapping between the elements of the domain and the range, it is some particular mapping. such as "successor", "ancestor", "solely owned by", or what have you. Consider the set of clock numbers: {12, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11}. Use this as the domain and range of two functions: "an hour later than" and "an hour earlier than". Without an x4, you can't tell which is which. -- John Cowan http://www.ccil.org/~cowan cowan@ccil.org To say that Bilbo's breath was taken away is no description at all. There are no words left to express his staggerment, since Men changed the language that they learned of elves in the days when all the world was wonderful. --_The Hobbit_