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Re: Proposals? Re: use/mention and reification

From: <jos.deroo.jd@belgium.agfa.com>
Date: Fri, 25 Jan 2002 00:43:04 +0100
To: Jan.Grant@bristol.ac.uk
Cc: connolly@w3.org, w3c-rdfcore-wg@w3.org
Message-Id: <OFC8CBB8BB.D008D6A3-ONC1256B4B.007E9FBF@bayer-ag.com>

> Can we get small amounts of words to describe these please? Currently
> there seem to be three proposals knocking around, with a possibility of
> others: (insert "this WG resolves that..." in front of all these)
>
>
> Proposal #1:
>
>     A resource R in an RDF graph G is said to be the reification
>     of the statement
>           S P O .
>     iff there exist in G the following statements:
>
>           R <rdf:type> <rdf:Statement> .
>           R <rdf:subject> f(S) .
>           R <rdf:predicate> f(P) .
>           R <rdf:object> f(O) .
>
>     where f is simply the identity function.
>
> Objections to this thus far appear to be (apologies if I'm putting words
> in people's mouths here):
>
>     danbri: objects on the basis that the intended interpretation
>     associated with the "utterer" of S P O may assign different
>     denotations to S, P and/or O - in other words, this is "broken"
>     when reifying statements taken from different sources in the
>     same graph (is that accurate, Danbri?)
>
>     danc: objects on the grounds that there's a use/mention
>     problem here, that it's hard to see how to make a MTetic
>     interpretation of this work. (again, correct me if I'm wrong).
>     (See his earlier messages on this) (- If there isn't a way
>     to make this make sense, then this seems to be a showstopper
>     objection)

no doubt, there is a use/mention problem
(I even asked my wife, and she was also sure...)

> Proposal #2: (Danbri or danc to fill in the blanks..?)
>
>     Looks like proposal #1 but f is defined differently.
>
>     f(X) = X    if X is a literal
>     f(X) = ?    if X is a URI-labelled resource

I would say f(X) = quote(X)

>     f(X) = ?    if X is a blank node

I wouldn't know that one

>     jang: might object if f isn't injective (or "one-to-one")
>
> Proposal #3:
>
>     this WG resolves that it's never heard of an eleven-letter
>     word beginning with "R". (DanC's option A)

Resolutions???

> (Other things that have been mentioned in passing include other ways of
> including statements in a "non-assertive" fashion)

so we could have e.g. at <uri0>
  <uri1> <uri2> <uri3> .
  <uri2> rdfs:range rdf:Description .
and at <uri3>
  <uri4> <uri5> <uri6> .
  <uri7> <uri8> <uri9> .
asserting the triples of <uri0>
doesn't mean asserting those of <uri3>

> Can we give these all fancy letter names and try again?

my dear...

--
Jos
Received on Thursday, 24 January 2002 18:43:32 EST

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