Charles Petrie <petrie@informatik.uni-kl.de>
Date:     Tue, 25 Aug 92 11:42:07 MET DST
From: Charles Petrie <petrie@informatik.uni-kl.de>
To: gruber@sumex-aim.stanford.edu
Cc: srkb@ISI.EDU
Subject:  "Theory"
Message-id: <9208251142.aa00992@inti.informatik.uni-kl.de>

> Why not call a set of shared definitions a "theory", as John requests?
> First, it should be obvious that "theory" is a fairly abused word in
> computer science.  It means a lot of things, but until today I never
> heard it used as the name for a set of definitions.  I reserve the
> technical term "theory" for the folks who are working out the
> important and subtle distinctions needed to handle contexts
> (microtheories, etc).  Second, whether there is a distinction between
> a set of definitions and an arbitrary set of axioms (which is one of
> the formal definitions of "theory") is a longstanding, interesting,
> and currently popular RESEARCH QUESTION in the knowledge
> representation community.

 I don't care so much about the word "ontology".  I'm perfectly happy
to say that computer scientists have appropriated this word from the
philosophers. We can discuss the computational differences (e.g.,
indexing, notation, power) of various ontologies, which I think of, in
a fuzzy manner, as definitions of the kinds of objects in the domain
of computation for some application.

  But I'm not ready to surrender the perfectly good technical term
"theory" to folks working on contexts. There is a formal definition of
it for computer science, and it's in the textbooks.  I will continue
to use it to mean a set of axioms (and their closure if I remember
>From Nilson), which may include object definitions.  If you, on the
other hand, reserve the word for context work, what are you going to
call what previously has been called "theories"?

  Otherwise, I agree with the largest part of your message and will
say something more later about the issue that is important to me.