Leo, (01)
At 04:33 PM 11/19/2002 -0500, Leo Obrst wrote:
>Ok, then it seems like we are all agreed, no?
>
>1) You need an expressive language for ontologies, the more expressive in
>general
>the better (with some qualification about expressive limits and tractability;
>Description Logics as a KR thread has tried to find a tractable sub-First
>Order
>Logic that is as close to FOL as you can get). (02)
I agree (03)
>2) It's useful to have multiple targeted syntaxes, depending on your needs. In
>OWL, we have an XML target (because the W3C and we build on XML and RDF/S and
>these languages are increasingly popular). I think Common Logic (ISO-KIF?) has
>multiple syntaxes too, no? (04)
Yes, I think that's a good approach. (05)
>But to me the real issue is: what is the base language of representation
>for an
>ontology? If you choose wrong, you may be able to express it in a syntax
>you like,
>but not be able to express the semantics you'd like. (06)
I agree. (07)
Adam (08)
>Leo
>
>Adam Pease wrote:
>
> > Mike,
> > I probably phrased my point too strongly. I'm not opposed to expressing
> > an ontology in an XML-based form, but we should be clear on why that is
> > needed. We translate SUMO into DAML (which is built on RDF and XML, which
> > means that we generate valid XML), and we do that so people who have
> > DAML-based tools can use SUMO.
> > XML is not a good thing in and of itself, but good only to the extent
> > that it serves some beneficial and well-articulated purpose connected to
> > the issue at hand, which in this case I take to be the storage, inspection,
> > manipulation and use of ontologies.
> >
> > Adam
> >
> > At 10:42 AM 11/19/2002 -0800, Uschold, Michael F wrote:
> > >Adam made two points:
> > >1. the language needs to be very expressive, such as KIF
> > >2. it is unnecessary to wrap the expressive language in XML syntax.
> > >
> > >My message only adressed 2, and I disagreed. I agree with 1.
> > >
> > >Mike
> > >
> > >
> > > -----Original Message-----
> > >From: owner-ontology_site22@xxxxxxxxxxxxx
> > >[mailto:owner-ontology_site22@xxxxxxxxxxxxx] On Behalf Of Leo Obrst
> > >Sent: Tuesday, November 19, 2002 4:59 AM
> > >To: ontolog@xxxxxxxxxxxxxxx
> > >Cc: 'Christian Fillies'
> > >Subject: Re: [ontolog] ontology tools and an ontology repository?
> > >
> > >I understand Adam's point, but will also underscore Mike's: i.e., yes, all
> > >of
> > >the Semantic Web languages do/will have an XML serialization, for
> exchange,
> > >etc. But it's also the case that only a specific intepreter will be
> able to
> > >make use of the RDF/S or OWL embedded or serialized in XML, i.e., an RDF/S
> > >or
> > >OWL interpreter. Perhaps that's obvious. What is not obvious is the
> internal
> > >language used and how things are represented internally. You might
> view the
> > >ontology as being represented in KIF and stored in a relational db, which
> > >has
> > >import/export converters to the exchange language of choice. Or the
> ontology
> > >is
> > >just a set of marked up documents stored as files. Or both (i.e, native
> > >RDF/S
> > >or OWL ontologies in a relational db) with its own query language (RQL,
> > >etc.)
> > >
> > >I will say that the language of representation does matter, i.e., you
> won't
> > >be
> > >able to express rich semantics in a languge that does not allow the
> > >expression
> > >of rich semantics. So I think Adam's point comes around to: KIF/Common
> Logic
> > >is
> > >the most expressive language semantically and all other translations will
> > >lose
> > >information (by definition, though I don't have a proof, I do know a bit
> > >about
> > >the various languages expressivity levels). So you don't want to express
> > >your
> > >ontologies in a rich language, then have them converted to specific
> targets
> > >(e.g., Horn Clauses, etc.), but in those conversion processes you will
> lose
> > >info -- unless of course you convert to an even more expressive logic,
> e.g.,
> > >a
> > >second or higher order language.
> > >
> > >Leo
> > >
> > >"Uschold, Michael F" wrote:
> > >
> > > > Adam,
> > > >
> > > > While I'm no expert on this, I think I disagree. Having an XML
> > > > serialization of KIF or whatever language you choose is a good idea
> - it
> > > > saves you from having to build a parser and makes it more widely
> > >available.
> > > > Just about everything these days has an XML serialization, e.g. RDF,
> > > > DAML+OIL, OWL etc. At the very least, there should probably be an
> export
> > > > to XML option.
> > > >
> > > > Do you think everyone else who thinks it is worthwhile to have an XML
> > > > serialization is (select one or more):
> > > > 1. wasting their time
> > > > 2. has different needs than is being discussed for Leo's ontology
> > > > repository.
> > > >
> > > > In either case, please explain your reasons.
> > > >
> > > > Mike
> > > >
> > > > -----Original Message-----
> > > > From: owner-ontology_site22@xxxxxxxxxxxxx
> > > > [mailto:owner-ontology_site22@xxxxxxxxxxxxx] On Behalf Of Adam Pease
> > > > Sent: Monday, November 18, 2002 6:14 PM
> > > > To: ontolog@xxxxxxxxxxxxxxx; ontolog@xxxxxxxxxxxxxxx
> > > > Cc: Christian Fillies
> > > > Subject: RE: [ontolog] ontology tools and an ontology
> repository?
> > > >
> > > > Monica,
> > > > XML is a general-purpose syntax, that can at some level
> accommodate any
> > > > information, just as an RDBMS can. However, the computational
> semantics
> > >of
> > > > a more expressive language will be lost.
> > > > For example, "Every horse has a head." is expressed in KIF as
> > > >
> > > > (=>
> > > > (instance ?X Horse)
> > > > (exists (?Y)
> > > > (and
> > > > (instance ?Y Head-PartOfBody)
> > > > (part ?X ?Y))))
> > > >
> > > > KIF defines what "=>", "exists", "and" etc mean, and what any
> > >computational
> > > > system employing those terms (that is conformant to KIF), must be
> able to
> > > > conclude based on their use. For example, if Ed is a Horse, then there
> > > > must exists a head that is part of Ed.
> > > > One could encode the statement above in many different ways in XML.
> > >For
> > > > example
> > > >
> > > > <implies>
> > > > <antecedent>
> > > > <clause>
> > > > <predicate value="instance">
> > > > <argument number=1 value="?X">
> > > > <argument number=2 value="Horse">
> > > > </clause>
> > > > </antecedent>
> > > > <consequent>
> > > > <existential>
> > > > <varlist><var name="?Y"></varlist>
> > > > <and>
> > > > <clause>
> > > > <predicate value="instance">
> > > > <argument number=1 value="?Y">
> > > > <argument number=2 value="Head-PartOfBody">
> > > > </clause>
> > > > <clause>
> > > > <predicate value="part">
> > > > <argument number=1 value="?x">
> > > > <argument number=2 value="?Y">
> > > > </clause>
> > > > </and>
> > > > </existential>
> > > > </consequent>
> > > > </implies>
> > > >
> > > > This is the sort of thing that's being done in the RuleML effort. The
> > > > problem though is getting all this "right" with respect to the
> semantics
> > >of
> > > > first order logic, and then creating tools that support those
> semantics,
> > >as
> > > > well as the XML-encoded input format.
> > > >
> > > > This seems unnecessary to me. I'd suggest using an ontology tool that
> > > > reads and understands KIF, instead of wrapping another layer of syntax
> > > > around it.
> > > >
> > > > Adam
> > > >
> > > > At 03:33 PM 11/13/2002 -0800, Monica Martin wrote:
> > > > >Why don't we consider using ebXML Reg / Rep to store these ontology
> > > > >artifacts, or am I missing something?
> > > > >
> > > > >-----Original Message-----
> > > > >From: Bob Smith [mailto:robsmith5@xxxxxxxxxxxxxx]
> > > > >Sent: Wednesday, November 13, 2002 10:52 AM
> > > > >To: ontolog@xxxxxxxxxxxxxxx
> > > > >Cc: Christian Fillies
> > > > >Subject: RE: [ontolog] ontology tools and an ontology repository?
> > > > >
> > > > >
> > > > >Hi Leo,
> > > > >
> > > > >Thanks for the XML.com survey of 53 tools...what a range of options
> > > > >today. What will the market look like in 18 months?
> > > > >
> > > > >A web-based ontology repository hosted on the site could help
> shape this
> > > > >evolving market by illustrating which features of various tools
> are more
> > > > >in demand than others (at least for this select audience...)
> > > > >
> > > > >I am using Semtalk (www.semtalk.com ) to support a few client's
> > > > >requirements.
> > > > >
> > > > >Since Peter is developing a survey format, I will just wait for his
> > > > >email.
> > > > >
> > > > >Thanks !!
> > > > >
> > > > >Bob Smith, Ph.D.
> > > > >Tall Tree Labs
> > > > >
> > > > >
> > > > >
> > > > >-----Original Message-----
> > > > >From: owner-ontology_site22@xxxxxxxxxxxxx
> > > > >[mailto:owner-ontology_site22@xxxxxxxxxxxxx] On Behalf Of Leo Obrst
> > > > >Sent: Wednesday, November 13, 2002 5:20 AM
> > > > >To: Ontolog-forums-cim3-net
> > > > >Subject: [ontolog] ontology tools and an ontology repository?
> > > > >
> > > > >
> > > > >All,
> > > > >
> > > > >We are considering one possibility for our site: an ontology
> repository,
> > > > >wherein folks can register ontologies and/or build ontologies using
> > > > >Web-enabled tools, possibly hosted at our site.
> > > > >
> > > > >So some questions:
> > > > >1) How do you feel about:
> > > > > a) our site supporting an ontology repository?
> > > > > b) our site supporting a Web-enabled ontology tool (for
> developing
> > > > >ontologies)?
> > > > > c) none of the above.
> > > > >
> > > > >2) Which ontology tools do you use?
> > > > > a) Can you characterize the tools: i.e., Web-enabled, ontology
> > > > >languages supported, cost/licensing, POCs, experience, etc.
> > > > > b) Do you know of a tool provider who might support such a public
> > > > >effort, hosted on our site?
> > > > >
> > > > >3) Which ontology languages (knowledge representation languages)
> should
> > > > >be the standard(s) for the ontologies?
> > > > > (Some examples: Ontolingua/KIF, Common Logic, OKBC, CycL, RDF/S,
> > > > >DAML+OIL, OWL, etc.)
> > > > >
> > > > >4) Additional Comments?
> > > > >
> > > > >Thanks!
> > > > >Leo
> > > > >
> > > > >--
> > > > >_____________________________________________
> > > > >Dr. Leo Obrst The MITRE Corporation
> > > > >mailto:lobrst@xxxxxxxxx Intelligent Information
> Management/Exploitation
> > > > >Voice: 703-883-6770 7515 Colshire Drive, M/S W640
> > > > >Fax: 703-883-1379 McLean, VA 22102-7508, USA
> > > > >
> > > > >
> > > > >
> > > > >--
> > > > >To post messages mailto:ontolog@xxxxxxxxxxxxxxx
> > > > >An archive of the [ontolog] forum can be found
> > > > >at http://ontolog.cim3.org/forums/ontolog
> > > > >
> > > > >
> > > > >--
> > > > >To post messages mailto:ontolog@xxxxxxxxxxxxxxx
> > > > >An archive of the [ontolog] forum can be found
> > > > >at http://ontolog.cim3.org/forums/ontolog
> > > > >--
> > > > >To post messages mailto:ontolog@xxxxxxxxxxxxxxx
> > > > >An archive of the [ontolog] forum can be found
> > > > >at http://ontolog.cim3.org/forums/ontolog
> > > >
> > > > --
> > > > To post messages mailto:ontolog@xxxxxxxxxxxxxxx
> > > > An archive of the [ontolog] forum can be found
> > > > at http://ontolog.cim3.org/forums/ontolog
> > > > --
> > > > To post messages mailto:ontolog@xxxxxxxxxxxxxxx
> > > > An archive of the [ontolog] forum can be found
> > > > at http://ontolog.cim3.org/forums/ontolog
> > >
> > >--
> > >_____________________________________________
> > >Dr. Leo Obrst The MITRE Corporation
> > >mailto:lobrst@xxxxxxxxx Intelligent Information Management/Exploitation
> > >Voice: 703-883-6770 7515 Colshire Drive, M/S W640
> > >Fax: 703-883-1379 McLean, VA 22102-7508, USA
> > >
> > >
> > >
> > >--
> > >To post messages mailto:ontolog@xxxxxxxxxxxxxxx
> > >An archive of the [ontolog] forum can be found
> > >at http://ontolog.cim3.org/forums/ontolog
> > >--
> > >To post messages mailto:ontolog@xxxxxxxxxxxxxxx
> > >An archive of the [ontolog] forum can be found
> > >at http://ontolog.cim3.org/forums/ontolog
> >
> > --
> > To post messages mailto:ontolog@xxxxxxxxxxxxxxx
> > An archive of the [ontolog] forum can be found
> > at http://ontolog.cim3.org/forums/ontolog
>
>--
>_____________________________________________
>Dr. Leo Obrst The MITRE Corporation
>mailto:lobrst@xxxxxxxxx Intelligent Information Management/Exploitation
>Voice: 703-883-6770 7515 Colshire Drive, M/S W640
>Fax: 703-883-1379 McLean, VA 22102-7508, USA
>
>
>
>--
>To post messages mailto:ontolog@xxxxxxxxxxxxxxx
>An archive of the [ontolog] forum can be found
>at http://ontolog.cim3.org/forums/ontolog (09)
--
To post messages mailto:ontolog@xxxxxxxxxxxxxxx
An archive of the [ontolog] forum can be found
at http://ontolog.cim3.org/forums/ontolog (010)
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