From lojbab@lojban.org Fri Sep 28 18:10:06 2001
Return-Path: <lojbab@lojban.org>
X-Sender: lojbab@lojban.org
X-Apparently-To: lojban@yahoogroups.com
Received: (EGP: mail-7_4_1); 29 Sep 2001 01:08:33 -0000
Received: (qmail 50949 invoked from network); 29 Sep 2001 01:08:33 -0000
Received: from unknown (10.1.10.27)
  by 10.1.1.220 with QMQP; 29 Sep 2001 01:08:33 -0000
Received: from unknown (HELO stmpy-1.cais.net) (205.252.14.71)
  by mta2 with SMTP; 29 Sep 2001 01:10:06 -0000
Received: from bob.lojban.org (dynamic244.cl8.cais.net [205.177.20.244])
  by stmpy-1.cais.net (8.11.1/8.11.1) with ESMTP id f8T1A1793539;
  Fri, 28 Sep 2001 21:10:01 -0400 (EDT)
Message-Id: <4.3.2.7.2.20010928205209.00bd17f0@pop.cais.com>
X-Sender: vir1036@pop.cais.com
X-Mailer: QUALCOMM Windows Eudora Version 4.3.2
Date: Fri, 28 Sep 2001 21:06:51 -0400
To: phma@oltronics.net
Subject: Re: [lojban] periodic hexadecimal reminder
Cc: lojban@yahoogroups.com
In-Reply-To: <3BB24208.3020001@reutershealth.com>
References: <Pine.LNX.4.33.0109261008130.662-100000@simba.math.ucla.edu>
  <0109261630250A.01489@neofelis>
Mime-Version: 1.0
Content-Type: text/plain; charset="us-ascii"; format=flowed
From: "Bob LeChevalier (lojbab)" <lojbab@lojban.org>

At 05:00 PM 9/26/01 -0400, John Cowan wrote:
>Pierre Abbat wrote:
> > I think {ju'u} is in the wrong selma'o. All other binary mex operands take
> > two numbers and return a number.

Not necessarily. That may be the most common usage. But "addition" in the 
context of non-numerical strings is usually interpreted as concatenation, 
and Mex is used to handle that as well. Mex allows all manner of 
operations, including operations on objects not normally considered to be 
mathematical. In Lojban you really can compare apples and oranges (using 
Mex). All you have to do is define what the basis for the comparison 
is. (In slot machines, a cherry is greater than a lemon.)

> >{ju'u} takes a naclerpoi and a number and
> > returns a number.

That is the standard mathematical application of ju'u. But when I was 
looking into Mex, I found all manner of strange notations and operations 
that might be portrayed using Mex.

> > ze bi'esu'i bi pi'i so = (7+8)*9
> > ze bi'esu'i bi ju'u so = ?
> > is it 14 (which is written 15 in base 9) or what?
>
>It's nonsense.

I'm not sure I agree; rather it is moot. I understand (a+b) base c to mean 
evaluate (a+b) assuming each is written in base c. It is only "nonsense" 
because there is no reason to have used the bi'e since there is no standard 
mathematical usage where different bases would be used for different 
numbers without explicitly marking them so that 7 + 8base9 implicitly means 
7 base 9 + 8 base 9.

Lojban does not purport to dictate the semantics of mathematics, which is 
self consistent only within a single axiomatic context.


--
lojbab lojbab@lojban.org
Bob LeChevalier, President, The Logical Language Group, Inc.
2904 Beau Lane, Fairfax VA 22031-1303 USA 703-385-0273
Artificial language Loglan/Lojban: http://www.lojban.org


