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Re: abstract model and reification

From: Dan Brickley <danbri@w3.org>
Date: Mon, 18 Sep 2000 14:07:55 -0400 (EDT)
To: "McBride, Brian" <bwm@hplb.hpl.hp.com>
cc: "RDF Interest (E-mail)" <www-rdf-interest@w3.org>
Message-ID: <Pine.LNX.4.21.0009181402470.7854-100000@tux.w3.org>
On Fri, 15 Sep 2000, McBride, Brian wrote:

> A colleague has pointed this out to me, from m&s:
> 
>   When a resource represents a reified statement;
>   that is, it has an RDF:type property with a 
>   value of RDF:Statement, then that resource 
>   must have exactly one RDF:subject property,
>   one RDF:object property, and one RDF:predicate
>   property.
> 
> Oh well ...

Hmmm... I'm sat here with Dave Beckett trying to figure out what this
might mean. Here's a possibly sneaky interpretation: the resource "in
itself" must have those properties, but an RDF implementation (database,
serialised graph etc.) might not have representations of those
properties, even though they (in some sense) exist in the abstract.  So,
the reading of the spec is that resources that are reifications of
statements will always have these four properties. But we don't
necessarily know what the values of those properties are. So we take the
'must' language to be an observation about the world, rather than about
data structures...

I'm not sure if I'm persuaded (Dave isn't ;-)

Dan
Received on Monday, 18 September 2000 14:08:57 GMT

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