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Re: RDF *already* supports literal subjects - a thought experiment

From: Antoine Zimmermann <antoine.zimmermann@deri.org>
Date: Tue, 13 Jul 2010 15:05:45 +0100
Message-ID: <4C3C72B9.1030707@deri.org>
To: "Houghton,Andrew" <houghtoa@oclc.org>
CC: Semantic Web <semantic-web@w3.org>
Le 13/07/2010 14:56, Houghton,Andrew a écrit :
>> From: semantic-web-request@w3.org [mailto:semantic-web-request@w3.org]
>> On Behalf Of Pat Hayes
>> Sent: Monday, July 12, 2010 07:12 PM
>> To: Graham Klyne
>> Cc: Sandro Hawke; Semantic Web
>> Subject: Re: RDF *already* supports literal subjects - a thought
>> experiment
>>
>> First, as others have noted, we do already have a workable, if ugly,
>> way to state what anyone might need to state with a literal subject in
>> RDF already: instead of writing the obvious
>>
>> <literal>  :p :o .
>>
>> one can write
>>
>> _:x :same<literal>  .
>> _:x :p :o .
>>
>> using whatever form of :same one prefers, such as owl:sameAs. So we
>> don't need another complicated work-around. The point of allowing
>> literals as subjects was to avoid having to use a work-around, not to
>> invent a new one; and also, in fact, to simplify RDF and make it more
>> elegant, also not a purpose which is served by yet another work-
>> around. So this idea doesn't really help.
>
> First let me say that I don't fully understand the issues here, I
> am not a expert, but I am trying to make sense of these issues in
> the context of my current and future semantic web practice. What
> Pat mentioned, above, actually made sense to me given the following
> statement in the RDF concepts document:
>
>   <http://www.w3.org/TR/2004/REC-rdf-concepts-20040210/#section-Literals>
>
>   3.4 Literals
>   Literals are used to identify values such as numbers and dates by means
>   of a lexical representation. Anything represented by a literal could
>   also be represented by a URI, but it is often more convenient or
>   intuitive to use literals."
>
> If *anything* represented by a literal could also be represented by a
> URI, then:
>
> _:x owl:sameAs<literal>  .
> _:x :p :o .
>
> makes perfect sense to me. However, wouldn't the range of owl:sameAs
> need to be expanded to include literals?

There is no need to expand the range of owl:sameAs because nothing 
restricts the range of owl:sameAs.



Regards,
-- 
Antoine Zimmermann
Post-doctoral researcher at:
Digital Enterprise Research Institute
National University of Ireland, Galway
IDA Business Park
Lower Dangan
Galway, Ireland
antoine.zimmermann@deri.org
http://vmgal34.deri.ie/~antzim/
Received on Tuesday, 13 July 2010 14:06:22 UTC

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