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Re: The Peter paradox isn't.

From: Jonathan Borden <jonathan@openhealth.org>
Date: Thu, 21 Feb 2002 09:12:20 -0500
Message-ID: <02a201c1bae1$c8d51420$0301a8c0@ne.mediaone.net>
To: "Jeremy Carroll" <jjc@hplb.hpl.hp.com>, "Peter F. Patel-Schneider" <pfps@research.bell-labs.com>, <phayes@ai.uwf.edu>
Cc: <www-webont-wg@w3.org>
Jeremy,

>
> The change I was imagining is that:
> - typed node production continues unchanged,
> - triples involving rdf:type continue unchanged
> But
>
> rdf:type rdf:type rdfs:Property .
>
> is false.
>
> So that the rdf document (namespace liberties)
>
> <rdf:RDF>
>   <rdfs:Property rdf:about="rdf:type" />
> </rdf:RDF>
>
> is a contradicition.
>
> And any use of rdf:type with rdfs:subPropertyOf is also a contradiction.
>
> i.e. a change to RDF Schema not to RDF M&S.
>
> Certainly if these changes impact deployed code then they are not minor.
>

Ok, I assume that "rdf:type" is used as an "is-a" or "is-instanceOf" link in
traditional semantic network terms, and that software making this
assumption, and drawing conclusions using these assumptions, will be judged
to behave correctly under the new revisions.

Notably (perhaps this is more apropos the rdfcore wg)

_:x rdf:type rdfdt:int (or http://www.w3.org/2001/XMLSchema-datatypes#int
for that matter)
_:x rdf:value "123"

_:y rdf:type rdfdt:int
_:y rdf:value "0123"

=>

_:x = _:y

perhaps really

_:x math:equals _:y

_under the current RDF_, that is I assert that current software that derives
this is behaving correctly. I suppose that I am defining an "=" operator to
which I have hardwired knowledge of integers, and you are free not to
"believe" my "=" operator, but I suspect that the desperate web hacker will
agree with me***

Jonathan

*** since do not claim to be a  professional logician, I volunteer to stand
up for the interests of the DWH.
Received on Thursday, 21 February 2002 08:48:00 GMT

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