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Re: [SKOS] OWL DL compatibility

From: Dan Brickley <danbri@danbri.org>
Date: Wed, 21 Feb 2007 12:20:18 +0100
Message-ID: <45DC2AF2.7070408@danbri.org>
To: Bernard Vatant <bernard.vatant@mondeca.com>
Cc: SWD WG <public-swd-wg@w3.org>, SKOS <public-esw-thes@w3.org>

Bernard Vatant wrote:
> Hi all
>> I'm still digesting the issue. But one immediate point: I am 
>> uncomfortable with excessive use of OWL's notion of "annotation 
>> properties". They're very much 2nd-class citizens in the OWL world. 
>> I'd rather define extra properties for class etc annotation, and 
>> restrict prefLabel, altLabel to SKOS individuals.
> +1
> The first objective IMO is to be able to integrate SKOS instances in an 
> OWL-DL framework. Using the SKOS vocabulary to label OWL elements is of 
> course appealing, but potentially confusing, and I'm not sure it's such 
> a good idea. OWL-DL has deliberately sacrified the linguistic aspects of 
> naming on the autel of logic, by putting NL labels and languages outside 
> the semantics. I think we (SKOS) should not mess up with that, or try to 
> patch that bug of OWL-DL which is actually a deliberate built-in feature 
> (AFAIK)
> But both OWL and SKOS should be clear on this. Want logic, rules, 
> inference, go the OWL-DL way but forget about dealing with the 
> linguistic aspects (or build your own ad hoc classes and properties). In 
> SKOS you'll have linguistic aspects in the semantics (hopefully at the 
> end of the day).

I strongly agree, perhaps predictably. In my just-sent second mail, I 
changed my preferred design idea very slightly. Instead of making a new 
set of labelling properties for the OWL classes, ... just make one that 
bridges to a "shadow" concept, ... this design is better, since *any* 
documentation properties designed for SKOS will, via our indirection 
property, also be applicable in the tidy logical world of OWL DL.

There is a pluralistic philosophy articulated in the RDFS spec which I 
stubbornly cling to: we need a huge variety of ways of capturing the 
"semantics" of terms. Simple logics, fancy logics, streaming video 
interviews, plain text, HTML hypertext, mapping to natural language(s), 
relationships with concepts in other vocabs, ... and plenty more.

http://www.w3.org/TR/rdf-schema/#ch_introduction

"""This specification does not attempt to enumerate all the possible 
forms of vocabulary description that are useful for representing the 
meaning of RDF classes and properties. Instead, the RDF vocabulary 
description strategy is to acknowledge that there are many techniques 
through which the meaning of classes and properties can be described. 
Richer vocabulary or 'ontology' languages such as DAML+OIL, W3C's [OWL] 
language, inference rule languages and other formalisms (for example 
temporal logics) will each contribute to our ability to capture 
meaningful generalizations about data in the Web. RDF vocabulary 
designers can create and deploy Semantic Web applications using the RDF 
vocabulary description language 1.0 facilities, while exploring richer 
vocabulary description languages that share this general approach."""

I believe the same applies to SKOS...

cheers,

Dan
Received on Wednesday, 21 February 2007 11:20:37 GMT

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