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Re: RDF-ISSUE-25 (Deprecate Reification): Should we deprecate (RDF 2004) reification? [Cleanup tasks]

From: Dan Brickley <danbri@danbri.org>
Date: Sun, 10 Apr 2011 17:05:54 +0200
Message-ID: <BANLkTikf196zvUNFC8SNoCiKxo_YNVxHnw@mail.gmail.com>
To: Pat Hayes <phayes@ihmc.us>, William Waites <ww@styx.org>, Richard Cyganiak <richard@cyganiak.de>, Ivan Herman <ivan@w3.org>, RDF Working Group WG <public-rdf-wg@w3.org>
On 9 April 2011 15:49, Pat Hayes <phayes@ihmc.us> wrote:
> On Apr 9, 2011, at 7:28 AM, William Waites wrote:
>> * [2011-04-09 13:09:15 +0100] Richard Cyganiak <richard@cyganiak.de> écrit:
>> ] ISSUE-25 is about the RDF reification vocabulary, which is a
>> ] built-in vocabulary for reifying *statements*. You are talking
>> ] about a common modeling practice in domain vocabularies for
>> ] reifying *relationships*. That has nothing to do with ISSUE-25.
>> Right, that was what I wanted to have explicitly clear. It's not the
>> idea or practice of reification that is to be deprecated but the
>> baked-in support for reifying binary relations.
> No, really, you have this wrong. It IS the idea of reification that is being deprecated; and this device that you have mentioned, of encoding an n-ary relation using a bundle of binary 'role' relations, is NOT reification. The two things are distinct. Using the name of one to refer to the other is going to cause a lot of confusion. Reification is using RDF to *describe* other pieces of RDF.

This mixup has historical roots in the evolution of the original RDF
Model and Syntax spec 97-99. I made a fairly lengthy writeup of this
last year, filed under 'rdf:value', in anticipation of such WG
discussions.  Details at

The M+S reification vocab is supposed to for describing statements
without them necessarily also being asserted; so using its 'rdf:value'
as part of a pattern for making n-ary claims was just downright

Ah well, better luck this time.


Received on Sunday, 10 April 2011 15:06:23 UTC

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