SUO: RE: Vote on SUMO
Jim,
. I am changing my votes on both ballots to NO, in order to
align with the principals posited by John Sowa below.
. Lack of a consensus on what the SUO product should be means
that all development at the moment is essentially experimental. That is no
basis for development of the final document.
Cheers Graham Horn
National Data Standards Unit
Australian Institute of Health and Welfare
================================================
Phone: 02.6244.1094
Fax: 02.6244.1199
Email: Graham.Horn@aihw.gov.au <mailto:graham.horn@aihw.gov.au>
-----Original Message-----
From: John F. Sowa [mailto:sowa@bestweb.net]
Sent: Tuesday, 14 August 2001 23:30
To: standard-upper-ontology@ieee.org
Subject: SUO: Vote on SUMO
I vote NO on the proposal to adopt the SUMO document as a candidate document
for an ontology standard.
Comments:
I voted yes on the proposal to continue work on SUMO as a working document,
and I believe that a lot of good work has been done.
However, the SUO workshop at IJCAI last week confirmed my doubts that there
is nothing resembling a consensus on what the SUO product should be. I
think that it is premature to recommend any of the current proposals as the
basis for a standard.
John Sowa
-----Original Message-----
From: Horn, Graham
Sent: Monday, 13 August 2001 14:18
To: 'John F. Sowa'; standard-upper-ontology@ieee.org;
<mailto:standard-upper-ontology@ieee.org;> cg@cs.uah.edu
<mailto:cg@cs.uah.edu>
Cc: phayes@ai.uwf.edu <mailto:phayes@ai.uwf.edu>
Subject: RE: Foundations for ontology
John,
. I wish I could spend more time digesting the work you have
done. It is evidently significant and perspicacious.
. Might I suggest you put a motion to the SUO group (or a
modification to an existing one) for us to consider.
. I suspect you are bringing issues to the forum that
transcend the considerations most of us have made to date.
. I believe we would be well served by considering our way
ahead in terms of the issues you have raised, as well as considering your
recommendations.
. What do others think?
Cheers Graham Horn
National Data Standards Unit
Australian Institute of Health and Welfare
================================================
Phone: 02.6244.1094
Fax: 02.6244.1199
Email: Graham.Horn@aihw.gov.au <mailto:graham.horn@aihw.gov.au>
-----Original Message-----
From: John F. Sowa [mailto:sowa@bestweb.net]
<mailto:[mailto:sowa@bestweb.net]>
Sent: Monday, 13 August 2001 13:42
To: standard-upper-ontology@ieee.org;
<mailto:standard-upper-ontology@ieee.org;> cg@cs.uah.edu
<mailto:cg@cs.uah.edu>
Cc: phayes@ai.uwf.edu <mailto:phayes@ai.uwf.edu>
Subject: SUO: Foundations for ontology
As I have said in many notes to SUO list, I have some concerns about any
ontology that is developed by hand. In two recent talks, I presented my
views of how ontologies should be developed. The first talk, which I
presented at ICCS on August 3, surveys the philosophical foundations.
Following are the slides:
http://www.jfsowa.com/pubs/signtalk.htm
<http://www.jfsowa.com/pubs/signtalk.htm>
The second talk, which I presented at an IJCAI workshop on knowledge
discovery on August 6, suggests automated or semiautomated methods of aiding
in ontology development. Following are the slides for that talk:
http://www.jfsowa.com/pubs/autotalk.htm
<http://www.jfsowa.com/pubs/autotalk.htm>
I had originally intended to make this one talk, but as it kept getting
longer, I split it in two. There will also be a paper, which I'll announce
later (when it is finished).
At IJCAI, I also attended a talk by Stuart Shapiro. The paper for that talk
included some comments about Cyc, which are very relevant to ontology
development by hand. The problems with keeping Cyc consistent indicate why
I believe that more autotmated and semiautomated tools are essential for
ontology development. I scanned the paragraphs about Cyc from the paper and
included them at the end of this note.
As I said at the SUO workshop at IJCAI, I believe that something along the
lines that Robert Kent has been proposing for IFF is a necessary component
of any ontology project. I would prefer to see SUMO split up into multiple
smaller theories that could be combined by belief revision methods.
John Sowa
________________________________________________________________________
Some Observations about Cyc
[The following comments on Cyc have been extracted from a paper that was
presented by Stuart Shapiro at an IJCAI Workshop (citation below). The
evaluation of Cyc is based on Cycorp documentation and on experience by the
first author (Frances Johnson) during a Cyc training course.]
Doug Lenat and Cycorp have developed Cyc [Cycorp, 200la] -- a large
knowledge base and inferencing system that is built upon a core of over a
million hand-entered assertions or rules about the world and how it works.
This system attempts to perform commonsense reasoning with the help of this
large corpus of beliefs (mostly default with some that are monotonic). It
divides its knowledge base into smaller contexts called microtheories which
contain specialized information regarding specific areas (such as troop
movement, physics, movies, etc.). Belief revision is performed within
microtheories or within a small group of microtheories that are working
together, and the system is only concerned with maintaining consistency
within that small group (as opposed to across the entire belief space). For
example: in an everyday context, a table is solid, but within a physics
context, it is mostly space (between atoms).
A belief can have only one truth value, so no microtheory can contain both p
and ~p. For example, ~p could be expressed as the proposition p with a
truth value of false. The technique for maintaining consistency is to check
for contradictory arguments whenever a proposition is derived or asserted
into a microtheory. When contradictions are found, their arguments are
analyzed, and a decision is made regarding the truth value of the
propositions involved. Rankings of beliefs, however, is not a part of the
system -- it uses specificity to determine the truth value of a default
belief. For example: Opus the penguin does not fly, even though he is a
bird, because penguins don't fly. If there can be no decision based on
specificity, the truth value of the default belief is unknown. A default
belief loses out to a monotonic one. And, lastly, according to Cyc trainers
and other contacts, contradictions that are purely monotonic bring the
system to a halt until they are fixed. During Cyc training, Johnson
attempted to prove this last statement and failed -- revision was performed.
The instructors were surprised, but thought the training interface might be
the cause. We plan to explore this further, but it is an example of a
system behaving differently than it is described.
As mentioned [above], Cyc did not perform as described, and there must be
some question as to other possible differences from design theory. Most
specifically, Cyc literature [Cycorp, 2001b] claims to keep the
microtheories consistent, for lack of a better word. When asked, contacts
agreed that, in spite of a cursory check, it was possible that unknown
contradictions might exist that had not, yet, been derived. In this sense,
Cyc can only guarantee that its microtheories are not known to be
inconsistent (or KS-consistent). Ideal terminology, such as consistent and
derivable, is often not appropriate for use with a large or complex
implemented system.
References
Cycorp [2001a] _Cycorp, Creators of the Cyc Knowledge Base_,
http://cyc.com <http://cyc.com>
Cycorp [2001b] _Features of CycL_, http://cyc.com/cycl.html
<http://cyc.com/cycl.html>
The original article from which these paragraphs were extracted:
Frances L. Johnson and Stuart C. Shapiro, "Redefining belief change
terminology for implemented systems," _Inconsistency in Data and Knowledge_,
Working Notes from IJCAI'01, Seattle, Washington, 6 August 2001, pp. 11-21