ontolog-forum
[Top] [All Lists]

Re: [ontolog-forum] Foundation ontology, CYC, and Mapping

To: "[ontolog-forum]" <ontolog-forum@xxxxxxxxxxxxxxxx>
From: Jack Park <jackpark@xxxxxxxxx>
Date: Wed, 17 Feb 2010 12:17:53 -0800
Message-id: <5179aafa1002171217t904ab45g789b87d787bb4e13@xxxxxxxxxxxxxx>
I would toss a +1 at this concept of starting somewhere and evolving
from there. OpenCyc makes sense. What else makes sense might be a
website for such a project,  for instance, http://code.google.com/ ,
which provides Subversion (and other) version control options, a wiki,
download area, etc. Perhaps there are other options.    (01)

Jack    (02)

On Wed, Feb 17, 2010 at 8:41 AM, John F. Sowa <sowa@xxxxxxxxxxx> wrote:
> Dear Matthew, Doug, and Pat C,
>
> Before getting to the details of your notes, I'd like to clarify the
> term FO, which Pat introduced for a Foundation Ontology.  I have no
> objection to using the term FO, but I would apply it to the totality
> of the theories (or microtheories) in an OOR.  The Cyc example of an
> upper ontology with many specialized microtheories would be an example.
>
> However, I would broaden the idea to support multiple theories at the
> upper levels, which might be incompatible.  For example, Matthew,
> Chris P, and Pat H have strongly supported a 4D ontology for the upper
> levels, but many other people prefer to use a 3D upper level.  For
> many of the lower level microtheories, the differences between a 3D
> vs 4D foundation are irrelevant.
>
> Pat C wants to use primitives based on Longman's dictionaries, but
> I objected that those terms are too vague, and an enormous amount
> of work would be needed to make them precise.  Therefore, I propose
> the following approach:
>
>  1. OpenCyc is freely available as open source, but Pat objected
>     that it has very few axioms.  However, Longman's terms have zero
>     axioms, and they have never been tested for their usefulness in
>     any ontology, certainly not in anything as large as Cyc.
>
>  2. Therefore, I recommend that we adopt the OpenCyc terms together
>     with the axioms available in OpenCyc as a "starter set" for
>     developing the Foundation Ontology.
>
>  3. But we would also welcome and encourage anybody with different
>     preferences to contribute more terms and theories to the FO.
>
>  4. When convenient, those new theories should adopt the same
>     spelling as the terms already in the starter set, but any
>     new terms (taken from Longman's or any other source anyone
>     might prefer) could also be used in those additional theories.
>
>  5. The complete hierarchy of theories for the FO would be
>     organized along the lines we've been discussing in these notes.
>
>  6. Pat's goal of finding a much smaller set of defining terms
>     (called primitives) could be done in parallel with the
>     development of the FO instead of delaying its development.
>
>  7. If and when a good set of primitives has been found useful,
>     a methodology based on them could be promoted for simplifying
>     further ontology development.  However, older theories that
>     use the older terms would remain available as long as anyone
>     needs them.
>
> I'm suggesting this as a compromise that would begin with a large
> tested set of terms already organized in a generalization/
> specialization hierarchy.  It would also accommodate new terms
> that could be added as needed from any source.  But if anyone
> wants to do any immediate implementation today, the OpenCyc
> terms can be used.  Any work done with them would be guaranteed
> to be supported by the full FO.
>
> MW> I think [the FO] is more than just a vocabulary, but I agree
>  > that great care would need to be taken not to introduce into what
>  > I am calling abstract theories axioms that did not contradict say
>  > the 3D and 4D axioms that would be introduced when they were
>  > combined with those theories.
>
> I agree.  In fact, one advantage of OpenCyc is that it doesn't have
> all the axioms (AKA old baggage) of full Cyc.  That implies that it
> is more general than Cyc and less likely to have unpleasant
> "surprises" (AKA inconsistencies).
>
> MW> However, having such [abstract theories] would greatly simplify
>  > mapping between say 3D and 4D ontologies. These would I think need
>  > to be carefully designed rather than just picking something up,
>  > since it is casually almost certainly made some upper ontology
>  > assumptions.
>
> I agree.  Many, if not most of those theories could be based on
> terms that are already in OpenCyc.  In fact, if you just adopt
> the terms by themselves without any axioms, there is no possibility
> of an inconsistency.  Then any axiom that is added could be tested
> for consistency with both the 3D and the 4D ontologies (along the
> lines that I suggested in my previous note).
>
> DF> An ontology with a single theory would complicate the idea of
>  > a foundational ontology as an interlingua to which all external
>  > ontologies can be mapped.
>
> Yes.  That is why I would prefer to use the name Foundation Ontology
> for the full hierarchy of all the theories in the OOR.
>
> DF> Competing external theories could be incorporated by defining new
>  > concepts/relations for the relata of the competing theories (which
>  > map directly to the terms of the source ontology) and then adding
>  > rules relating them with the ostensible "sameAs" terms already in
>  > the foundational ontology.
>
> PC> Yes, but I would express the process as "logically specifying
>  > the terms of each extension ontology using only the terms in the
>  > FO" rather than "map directly" since that suggests that the
>  > entities in the extension ontology are already on the FO, which
>  > in general they will not be.
>
> I would expect the FO to be completely open-ended so that the
> number of useful terms would increase indefinitely.  There could
> also be a small subset of recommended defining terms.  (I wouldn't
> even object to calling them "primitives".)
>
> But we do have to recognize that many "primitives" may be very
> underspecified.  For example, the term PointInTime should be neutral
> with respect to a 3D or 4D ontology. For lower-level microtheories,
> you might have a general theory called Hiking, which would use
> PointInTime without any dependencies on 4D or 3D.  But if there are
> dependencies, one could have common specializations of Hiking with
> either of the two upper-level theories to generate the subtheories
> Hiking4D and Hiking3D.
>
> JFS> But if you think of [the FO] as a collection of theories organized
>  >> in a hierarchy, no single theory ever changes.  Instead, each
>  >> innovation adds another theory to the hierarchy, which may be a
>  >> generalization, a specialization, a sibling, or a cousin of some
>  >> other theory.  You  can also compare and combine theories.
>
> DF> Agreed.  This is part of the reasoning behind Cyc method of
>  > "microtheories" or contexts....
>
> PC> And that would be true for the FO and its extensions also. But there
>  > is an additional aspect to the FO as I have proposed it.  The CYC
>  > BaseKB is part of every other more specialized microtheory, but it
>  > was not designed as, nor used as, an inventory of basic elements that
>  > is sufficient to specify (as combinations) the intended meanings of
>  > the symbols that are in all of the other linked microtheories.  CYC
>  > didn't try that tactic, which could have been very informative.  But
>  > a proper test would in any case require that a good number of separate
>  > groups with different applications and viewpoints try to use the same
>  > FO to describe their different domain ontologies.
>
> This comment mixes two different goals:
>
>  1. A large useful ontology that people can begin using ASAP.
>
>  2. A project to determine whether a small subset of terms (called
>     primitives) is sufficient to define everything else and would
>     thereby promote interoperability.
>
> Different people may have different priorities.  My personal preference
> is to emphasize #1.  I have no objection to anyone who prefers #2, but
> I would not want to tell people who have a day job that they have to
> wait until #2 is finished.  My recommendation is to start with #1 and
> let anyone who wants #2 to *extract* some subset from #1 in order to
> test that hypothesis.  If that hypothesis seems to be justified, then
> the results could be developed into a methodology for using, adapting,
> and streamlining the much larger resources of #1.
>
> But I would never suggest that people who need an ontology today should
> wait until project #2 is completed.  The above proposal lets people
> start new projects using OpenCyc and rest assured that the FO would
> continue to support them in the future.
>
> JFS> You can think of context as some additional statements S that are
>  >> added to a theory T to specialize it for some particular application.
>
> DF> If the context referred to is what Cyc calls a DataMicrotheory,
>  > then the statements added are qualitatively different from those
>  > in the basic theory.
>  >
>  > A context might close T's open world assumption, such that T2 has
>  > a closed world assumption.  T and T2, in such a case, would be
>  > different types of theory.
>
> That's a good point.  It illustrates an important advantage of
> starting with OpenCyc (or some subset of it).  We can take advantage
> of the 26 years of experience in developing Cyc.  We don't have to
> adopt every one of their decisions, but when we diverge, we should
> have a good reason for doing so.
>
> DF> An FO would need to have a reasonably restrictive generalization
>  > of classes included in any microtheory that is to be mapped to it.
>  > Defining "reasonably restrictive" could be hard, but it seems to me
>  > that SUMO (with extensions) and Cyc both would currently meet this
>  > requirement.  Including concepts from UMLS and GoodRelations would
>  > lower the rough lower edge of the directed acyclic graph of classes
>  > in several key areas.
>
> I'm all in favor of building on good work that has been done in other
> systems.  We should make sure that the licensing terms are compatible
> and get explicit permission to use whatever is incorporated in the FO.
>
> DF> One question is on what basis should individuals should be included
>  > in an FO.  Certainly units of measure should be.  Currencies &
>  > countries surely.  Cities and every instance in the GeoNames base?
>  > How should the selection of people to add be made?  Organizations?
>  > Conceptual works (books, movies, songs, albums, paintings,
>  > constitutions, poems, ...)?  Sports and games? Events (disasters,
>  > wars, elections, mergers, ...)?  Etc.
>
> Those are excellent questions.  I would prefer to err on the side of
> being more inclusive.  My suggestion would be to keep the axioms
> relatively free of individual names, but to have an associated
> database that would store as much as anyone might find useful.
>
> However, there will undoubtedly be many very useful specialized
> theories, such as US IRS Tax Code for 2010.  The most qualified
> people to develop such a theory would be the IRS.  But the FO
> could maintain pointers to such theories stored and maintained
> in compatible formats by other organizations.
>
> DF> The breadth of coverage of the proposed FO needs to clarified.
>  > Is it to be an ever-expanding set of all terms defined in any
>  > ontology?   Should it include all individuals ever defined on
>  > the Semantic Web?
>
> Those are important policy decisions.  Since the SW is expanding
> very rapidly, we can't hope to incorporate it into the FO.  But we
> must have interfaces to it that would allow any application to
> access it as needed.  In fact, if we do a good job on the FO,
> the SemWebbers might take notice and adapt their technology to
> facilitate sharing in both directions.
>
> DF> Or could there be a basic, relatively fixed, FO to which an
>  > expanding number of contextually restricted, but still centralized,
>  > ontologies are related?  I could see such for brand-name products,
>  > GeoNames, UMLS, IMDB, GeneBase, etc.
>
> PC> The FO itself should try to include all primitives that are used
>  > by more than a small set of specific domain ontologies, and only
>  > those non-primitive elements that are needed for ease of use and are
>  > non-controversial.  Primitives required by domain ontologies should
>  > also be maintained, but as part of a domain extension.
>
> The goal of getting a useful FO ASAP implies that we should start
> with a much larger set of terms than Pat has in mind.  But that may
> be an advantage.  The goal of extracting a smaller number of defining
> terms can be guided by usage patterns.  Those terms that are most
> widely used would be prime candidates.  The other terms could be
> redefined in terms of them.
>
> I would expect an FO committee to be similar (in some ways) to the
> W3C.  It would define formats, guidelines, policies, etc., and
> encourage other groups to adopt them and make their work compatible.
>
> John
>
>
> _________________________________________________________________
> Message Archives: http://ontolog.cim3.net/forum/ontolog-forum/
> Config Subscr: http://ontolog.cim3.net/mailman/listinfo/ontolog-forum/
> Unsubscribe: mailto:ontolog-forum-leave@xxxxxxxxxxxxxxxx
> Shared Files: http://ontolog.cim3.net/file/
> Community Wiki: http://ontolog.cim3.net/wiki/
> To join: http://ontolog.cim3.net/cgi-bin/wiki.pl?WikiHomePage#nid1J
> To Post: mailto:ontolog-forum@xxxxxxxxxxxxxxxx
>
>    (03)

_________________________________________________________________
Message Archives: http://ontolog.cim3.net/forum/ontolog-forum/  
Config Subscr: http://ontolog.cim3.net/mailman/listinfo/ontolog-forum/  
Unsubscribe: mailto:ontolog-forum-leave@xxxxxxxxxxxxxxxx
Shared Files: http://ontolog.cim3.net/file/
Community Wiki: http://ontolog.cim3.net/wiki/ 
To join: http://ontolog.cim3.net/cgi-bin/wiki.pl?WikiHomePage#nid1J
To Post: mailto:ontolog-forum@xxxxxxxxxxxxxxxx    (04)

<Prev in Thread] Current Thread [Next in Thread>