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Re: layering (5.3, 5.10): Sardinia compromise?

From: Jonathan Borden <jonathan@openhealth.org>
Date: Thu, 20 Jun 2002 14:02:40 -0400
Message-ID: <03c501c21884$ad40ccd0$0a2e249b@nemc.org>
To: "Massimo Marchiori" <massimo@w3.org>, <www-webont-wg@w3.org>

Massimo,

> > >
> >
> > By "different domain" are you suggesting that OWL might provide
> > an entirely
> > different semantics for a graph of e.g. N-triples, than RDF, i.e. that
> > triples become the _syntax_ of OWL which provides its own model
> > theory (i.e.
> > semantics) ?
>
> Precisely so. When studying years ago the possible kind of semantical
> extensions (in the field of RDF-logic), I've met a variety of options,
> and explored the most liberal ones too. And the most liberal one
> (well, one of the most liberals) is just to use different domain
> of interpretations, and establish some very weak semantic link.
...
> Now, I don't view this as a problem at all: RDF can be seen just as
> a syntax, and it's very reasonable that in order to define some
> meaningful language you have to constraint such syntax (think eg
> at programs written in C and their corresponding parsers).
> There might be many rules, but that's just a natural consequence
> of defining a language.

Certainly, this is a very sensible approach. This position, may I summarize,
is that we define the semantics of OWL using RDF triples as syntax.

>
> I'll come back on the specific 101's approach at a later stage, but anyway
> I see it much better than dark-triples, as it embraces the
different-domains
> idea
> rather than the dark-triples one. Just, beware of the "OWL extends RDFS"
> foundation,
> that might be the real source of all the trouble...
>

To be clear about "dark triples" your position, if I've interpreted
correctly, is not "much better" rather, entirely _consistent_ with "dark
triples" which is saying exactly that: let us use certain RDF triples for
syntactic purposes _on which_ we may define our semantics. The "different
semantics" approach is for OWL to consider _all_ RDF triples 'initially
dark' but 'enlightened' by the OWL MT according to the OWL MT.

An intermediate position, which I favor, is to keep RDF triples which
discuss individuals and facts englighted according to the RDF MT, but to use
RDF triples which carry the OWL syntax, just as syntax to be enlightened by
the OWL MT. This is also consistent with the position that triples having a
predicate in the OWL namespace i.e. whose root URI is 'owned' by OWL (ie.
the WebOnt WG via its position in the W3C) be triples whose meaning ought be
defined by OWL -- in other words 'reserved' to OWL.

I think a number of people are effectively saying the same thing, but using
different language.

Jonathan
Received on Thursday, 20 June 2002 14:07:55 GMT

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