UOS-conveners:
I think that the comments of
Mills Davis (below, sent to Brand Niemann) provide a good example of the work
that the upper ontology community has to do in order to explain to the wider
world - including most people in the IT field - why upper ontologies are
important for achieving broad semantic interoperability among diverse
applications.
The need for formalized definitions in
ontologies has been preached by Doug Lenat and others since before 1990. The basic ideas go back 50 years to
the birth of "AI". One might have
supposed that by now everyone in IT would understand why computers need
precise definitions to do logical inferencing
on knowledge.
MW: There is a lot more to ontology than inferencing
(though I appreciate that that is the primary interest of most people here,
and I also think inferencing is some of the most interesting stuff). All IT
systems have an ontology, often it is implicit, and even where it is explicit
it is usually very poor (even if one allowed the most favourable
interpretation). So there is a great deal that can be done (and pots of money)
in using upper ontologies for improving existing traditional systems and
helping to reduce the costs of new ones by improving design. Even
after that there is a lot to be done in integrating existing systems (as
we know mapping between any two non-trivially different
ontologies requires an FOL equivalent
capability).
But this understanding is
apparently still confined mostly to a small group who work with axiomatized
ontologies. Most of us in this
group understand the potential benefits of automated reasoning over large
knowledge bases, but some who are (properly) concerned with what can be done
immediately remain to be convinced, either of the ultimate potential, the time
required to get there, or the economic or
social feasibility of the goal.
MW: I think (know) there is a big gap between where most
people are and the high end of what ontology offers. My experience in
convincing people in any argument is that you have to start from where they
are, which generally is with traditional systems that are too expensive and
don't really work.
It appears to me that those who
are convinced of the benefits of upper ontologies need more effort at outreach
to a broader audience. The
UOS was intended to help in that goal.
The result may depend on how much we can achieve on Tuesday.
Mills has been familiar with
applications of knowledge representations for years, and yet he still
asks:
"why have one upper-level
ontology when you can have them all? "
The answer, of course, is that
having more than one upper-level ontology makes accurate and automated
semantic interoperability impossible (or in the more cautious words of
the joint communiqué
draft):
" . . . use of some formally defined common
upper ontology by an organization or community is the most cost-effective
method for achieving semantic interoperability that can scale from a few
applications to diverse knowledge-based reasoning systems ".
MW: That is not jsut
one UO at all, just one for a particular organization or community.
However, if there are a few UO's that have good mappings between them, then
you have more flexibility, and probably more
power.
. . . but Mills is apparently not
convinced. And I think that he
represents a very large fraction of the IT community in this respect.
I think that we cannot assume
that just because someone has been exposed to arguments about the importance
of upper ontologies, s/he will have understood the point. Even worse, we cannot assume that
someone who has access to, or been pointed to, discussions of the need for
upper ontologies has even read such discussions, let alone understood
them. The issues are apparently
complex enough that they need to be phrased as simply and succinctly as possible, and be
accompanied by pointers to examples illustrating how UOs can benefit
users. The former might be helped
by the Joint Communique, which can be redistributed wherever it may do some
good. The examples are an issue
we need to discuss on Tuesday and Wednesday morning.
MW: My case
studies will be in this area of tackling the problems people know they have
today using a UO.
Another point that has come up
in the course of these discussions is that most of those who are building
domain ontologies or other knowledge classifications need something simple to
work with, if they are going to align such knowledge bases with a more general
concept classification. This also
impinges on the question of how much agreement can be achieved among the upper
ontologists, and whether a "common subset" can be found. These issues were raised by
comments of (among others) Barry Smith, David McComb, Mills Davis, John Sowa,
and Roy Roebuck.
But to serve the purposes of
semantic interoperability, I think that most of us would agree that even a
"simplified" upper ontology must have
sufficient formalization to avoid the common ambiguities associated with
linguistic terms. This recalls
Einstein's dictum: "A
theory should be made as simple as possible, but no simpler. "
My own appreciation of these
concerns leads me to feel that it would be very helpful to have an axiomatized UO fragment that is simple
enough to be rapidly and widely adopted so that it is highly visible, but
axiomatized to sufficient precision to avoid the major ambiguities in
interpreting the meanings of the terms, and can demonstrate to a wide audience
the advantages of a common, formally defined higher-level ontology to enable
information transfer among semantic modules. Perhaps a common subset will serve
such a purpose.
MW: I do think
there is work that can be shared, and that this would prove valuable, but I
think it might end up looking a little different from what you seem to be
envisioning.
The note of Mills Davis is
attached directly below.
The current situation reminds
me of the "muckraker" allegory from "Pilgrims Progress" and I have attached
that reference below as well, with a short comment.
Pat
Patrick
Cassidy
MITRE Corporation
260 Industrial Way
Eatontown, NJ
07724
Mail Stop: MNJE
Phone: 732-578-6340
Cell: 908-565-4053
Fax:
732-578-6012
Email: pcassidy@xxxxxxxxx
=======================================================
Note of Mills Davis to Brand
Niemann
===========================================================
I talked with Steve, and
yes, I'll do 20 minutes with Doug Lenat to
set a business context
for ontology. Why? Because, at a minimum, it
is good that the
various ULO custodians are agreeing to work together
to cross link
and explore samenesses and differences between their
approaches.
This is the essence of the public statement they will
come up with
at the end of the second day. I support their desire to
work
together because I believe that the semantic wave is a big one
and
that all contributions are welcome and encouraged.
If you were to ask
me where I think that this ULO activity will come
out, then I
have the following thoughts:
(1) If the ULO quest is to arrive at one
upper level ontology, then I
think that the result will not be this.
Rather, that there will
emerge some few, a small set of primitives,
that link to low level
concepts or instances of interest via a
direct binary relationship;
then, between these layers of
abstraction, any taxonomy or upper
level ontology can be interposed,
allowing us to choose which is the
best for our purposes. Bottom
line, why have one upper-level ontology
when you can have them
all? I suspect that the only reason to be
looking for one
upper level ontology would be if you believed that
relational
databases would be for ever and that every item of data
must
have one and only one tag.
(2) Secondly, my interest is in the
development of a "scientific
method" for testing and evaluating the
efficacy and validity of
metaphysical patterns (ontology). In an era
of knowledge computing,
its is of critical importance to be able to
validate and ground the
ontology specifications in experimental
data. Here, I think that the
focus should shift from the nouns
(concepts) to relationships and the
theories that underly these
relationships. Nouns require conventions
and agreements.
Relationships and the theories that underly them are
much more
limited and scientific.
Bottom line: I applaud and encourage the
efforts of this UO
community. By coming together, I hope they
deliver value. At the same
time, I'm reserving judgement (or,
remaining agnostic regarding the
value, pending evidence), and am
harboring a supposition that in the
next year or so, technology may
be emerging that will obviate UO
arguments by subsuming all of these
disparate approaches and
subjecting them to tests of efficacy.
====================================
Pat Cassidy: fable for the
day.
===================================
There will always be a tension
between those who are concerned with what is concrete and doable immediately,
and those who are concerned about the things that can be done in
the near future that represent a
qualitative improvement over the immediate. The fable of the "muckraker" from
"Pilgrim's Progress" puts that in an allegorical (though religious) form:
From Paul Bunyan, Pilgrim's
Progress, stage 2
------------------------
This done, and after those things had been
somewhat digested by Christiana and her company, the Interpreter takes them
apart again, and has them first into a room where was a man that could look no
way but downwards, with a muck-rake in his hand. There stood also one over his
head with a celestial crown in his hand, and proffered him that crown for his
muck-rake; but the man did neither look up nor regard, but raked to himself
the straws, the small sticks, and dust of the floor.
Then said Christiana, I persuade myself
that I know somewhat the meaning of this; for this is a figure of a man of
this world: is it not, good sir?
INTER. Thou hast said right, said he; and
his muck-rake doth show his carnal mind. And whereas thou seest him rather
give heed to rake up straws and sticks, and the dust of the floor, than to do
what He says that calls to him from above with the celestial crown in his
hand; it is to show, that heaven is but as a fable to some, and that things
here are counted the only things substantial. Now, whereas it was also showed
thee that the man could look no way but downwards, it is to let thee know that
earthly things, when they are with power upon men's minds, quite carry their
hearts away from God.
-----------------------------
[PC] Apparently, a common upper
ontology that can enable semantic interoperability "is but as a fable to
some". I hope that the UOS
meeting can help to provide evidence that the benefits of upper ontologies are
more "substantial" than many in the wider world currently believe.