Re: Ontological EDI & Wittgenstein
fritz@rodin.wustl.edu (Fritz Lehmann)
Date: Wed, 28 Sep 94 22:24:51 CDT
From: fritz@rodin.wustl.edu (Fritz Lehmann)
Message-id: <9409290324.AA12782@rodin.wustl.edu>
To: scott@ontek.com
Subject: Re: Ontological EDI & Wittgenstein
Cc: cg@cs.umn.edu, edi-new@tegsun.harvard.edu, srkb@cs.umbc.edu
Sender: owner-srkb@cs.umbc.edu
Precedence: bulk
Scott Dickson of Ontek, Inc. responded to my recent
"ontological EDI" posting, and as usual I agree with
his cautionary words.
One point deserves explaining. He said among other things:
----begin quote----
Fritz Lehman wrote (regarding classification and constraints):
>And we can agree completely that no barge (X12
>Element 211:BRG) is a suburb, despite the natural imprecision of both
>concepts.
I would not agree with such a statement. I recall designs by the architect
Paolo Soleri of floating self-contained cities, or arcologies. One could
easily imagine tethered floating suburbs, which one could easily classify
as large barges.
This observation is not as whimsical as it seems. It illustrates a basic
difference between real-world classification schemes implemented in humans
and abstract classification schemes encoded in logic. A better expression
of the _real_ "constraint" is "a barge is usually not a suburb" or maybe "a
barge is almost always not a suburb". Of course, we humans almost
certainly don't have such a "constraint" as part of the mental processes
that recognize barges and suburbs. We only construct such a "constraint"
when we want to give an example of a "constraint" of this kind.
----end quote----
Yeah, I thought about possible exceptions to the mutual
exclusion of BARGE and SUBURB; that's why I said "we can agree
completely that no barge ... is a suburb" rather than "No
barge can be a suburb." Practical business transactions
have an advantage in that they deal with the world as it is.
They have that "common ground", and they don't have to be
concerned about science-fiction worlds, etc. I could have
said "No barge is a Social Security Number" -- I just
happened to write down the BARGE (as measurement unit) code
from the X12 standard in my notes. In fact, I think it might be
universally true that "No barge is a suburb" in the intended
(undefined of course!) EDI X12 sense, even in hypothetical
worlds. A named suburb might be _made_ of a barge or several
barges, but it _is_ not a barge (especially as an X12 211
measurement unit!). I'm all for making fine distinctions,
but this particular caveat of Scott's would be cured, I
think, by the very ontology that we are recommending.
A part of town could NOT be a physical measurement unit.
With "ontological EDI", the _computer_ would know this, not
just the human users.
Yours truly, Fritz Lehmann
GRANDAI Software, 4282 Sandburg Way, Irvine, CA 92715, U.S.A.
Tel:(714)-733-0566 Fax:(714)-733-0506 fritz@rodin.wustl.edu
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