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Re: A DTD for the abstract RDF model

From: Graham Klyne <GK@dial.pipex.com>
Date: Mon, 09 Oct 2000 12:55:21 +0100
Message-Id: <4.3.2.7.2.20001009124729.00b4fa40@pop.dial.pipex.com>
To: Tom Van Eetvelde <tom.van_eetvelde@alcatel.be>
Cc: www-rdf-interest@w3.org
I broadly agree with your comments about literals -- they occupy an 
uncomfortable position in the RDF world view.

BUT, I would say that they are often a convenience when talking about RDF 
graphs.  It's often easier to write a string than invent and describe a 
resource.  I've not given much thought to this, but I think I'd like to see 
literals treated as a shorthand (a syntactic sugar) for an anonymous 
resource that somehow incorporates the literal value.  The issue does still 
arise of needing to have some grounding for values in an RDF graph -- 
'data:' URIs, perhaps?  (Which reminds me of an English joke:  we have a 
town called Bracknell, of which it used to be said "Bracknell is a 
collection of road junctions with signposts pointing to Bracknell".)

#g
--

At 11:08 AM 10/9/00 +0200, Tom Van Eetvelde wrote:
>Why literals in RDF?
>
>First of all, when you look at the philosophy of RDF, you need to be able 
>to tell anything about anything. When I use Literals in my RDF documents, 
>nobody is able to elaborate on them as Literals may not be referred to. 
>This is a bit strange.
>
>Currently, Literals are items you are not allowed to say anything about. 
>One could issue that Literals are like the atomic buidling blocks of an OO 
>model: OO builds on characters, decimals, ... datatypes which do not 
>belong to the OO model. They are needed to bootstrap the OO model. Still, 
>this viewpoint on Literals doesn't hold.
>The reason is that Literals do not contribute anything to the RDF model. 
>On the contrary, they introduce restricitons (no arrows may origine in 
>Literals) that are against the RDF model philosophy. And this while 
>literals are not really needed! They just make you step out of your 
>trippel model. The Literals that I use in my application domain could be 
>resources modelled in another application domain. If you ask me, get rid 
>of the Literals in the RDF model. When you take a graphical example, it 
>only makes it clearer (see attachment).



------------
Graham Klyne
(GK@ACM.ORG)
Received on Monday, 9 October 2000 07:59:48 GMT

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