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Fw: URI/RDF math

From: Jonathan Borden <jonathan@openhealth.org>
Date: Tue, 18 Mar 2003 15:23:09 -0500
Message-ID: <005401c2ed8c$346b8060$b6f5d3ce@L565>
To: "\"Peter F. Patel-Schneider\"" <pfps@research.bell-labs.com>
Cc: <www-rdf-logic@w3.org>

Peter F. Patel-Schneider wrote:

> >
> > Well you certainly can use URIs to encode integers and then use such
URIs
> > in owl:ObjectProperty's if that is what you want.  However, you are not
> > going to get OWL to understand your encoding, and thus OWL will be
> > (blissfully) unaware of any connection between integer:5 and the integer
> 5.
> >
> > You are going to get just about as much of the meaning of integers using
> > this proposal as you would get of universal quantification using an
> > encoding like:
> >
> > <log:forall>
> >   <log:variable rdf:resource="x" />
> >   <log:formula>
> >     <rdf:Statement>
> >       <rdf:subject rdf:resource="x" />
> >       <rdf:predicate rdf:resource="ex:loves" />
> >       <rdf:object rdf:resource="ex:Mary" />
> >     </rdf:Statement>
> >   </log:formula>
> > </log:forall>
> >

Right ... for the current purposes of RDF and OWL, URI(ref)s are treated as
opaque strings. At some point when we consider what a triple "means" we run
into the question of what a URI(ref) means. The issue of what an individual
URIref means hasn't been solved (evidence the social 'meaning' discussions).

The meaning of some URIs might be determined by dereferencing the URI,
looking at what we get back, and using that as a definition of the URI.
Other URIs might be defined by *inspection*, for example the "data:" scheme:

data:text/plain;this is a piece of data
data:application/xml;<this>is a piece of XML</this>

I'm just wondering how so embedding an integer in a URI might be used by a
layer 'strapped onto' OWL --- note that I haven't defined exactly what
'strapped onto' means, just raised the possibility.

Jonathan
Received on Tuesday, 18 March 2003 15:23:17 GMT

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