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Re: missing (and incorrect) RDFS axioms

From: Graham Klyne <Graham.Klyne@MIMEsweeper.com>
Date: Sat, 09 Nov 2002 11:06:17 +0000
Message-Id: <5.1.0.14.2.20021109110324.03c70110@127.0.0.1>
To: "Jos De_Roo" <jos.deroo.jd@belgium.agfa.com>
Cc: Pat Hayes <phayes@ai.uwf.edu>, w3c-rdfcore-wg@w3.org

At 09:34 PM 11/8/02 +0100, Jos De_Roo wrote:
> > > > rdf:object          rdfs:range  rdfs:Resource .                   *
> > >
> > > ...did we agree that all literals are resources?

Er... what *is* a literal here:   if, for some datatype, we have:

     v = L2V(l)

is l the literal, or v?   I think v is a resource (member of IR) but l is 
not necessarily so.

I think Jeremy's argument applied to v.

Intuitively, I would say that l is the literal, not v.  E.g. the MT draft, 
section 1.2, describes a literal as a "referring expression".

But in another message, Pat says:
>aaa ppp <any literal, even a bad one>
>
>-->
>
>aaa ppp _:xxx .
>_:xxx rdf:type rdfs:Literal .

which seems to be saying that v is the literal (if a literal is any member 
of rdfs:Literal).  This is borne out by the MT draft (e.g. section 3.3.1).

I'm beginning to wonder what is the point of rdfs:Literal.  Fort example, 
looking at:
    rdfs:comment rdfs:range rdfs:Literal
that simply seems to say that the range is a value that *can* be expressed 
using a literal, not that it *must* be expressed that way.  Which I think 
is quite right.  Why do we care?

#g
--

At 09:34 PM 11/8/02 +0100, Jos De_Roo wrote:
> > > > rdf:object          rdfs:range  rdfs:Resource .                   *
> > >
> > > ...did we agree that all literals are resources?
>
>well, it's in the current MT draft
>rdfs:Literal rdfs:subClassOf rdf:Resource .
>(and I, for one, strongly agree)
>
> > regardless, it's redundant to say range Resource.
> > Please let's don't.
>
>I agree and try to avoid it in
>http://www.agfa.com/w3c/euler/rdfs-rules
>(which is still in a web with owl)

-------------------
Graham Klyne
<GK@NineByNine.org>
Received on Saturday, 9 November 2002 06:35:28 EST

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