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Re: "meaningless terms" verbage for Primer

From: Frank Manola <fmanola@mitre.org>
Date: Mon, 09 Dec 2002 13:43:46 -0500
Message-ID: <3DF4E462.856E490A@mitre.org>
To: Patrick Stickler <patrick.stickler@nokia.com>
CC: w3c-rdfcore-wg <w3c-rdfcore-wg@w3.org>

Patrick Stickler wrote:
> 
> Here is my proposed verbage regarding terms with undefined
> semantics, for inclusion into the Primer. Frank, feel free
> to wordsmith freely.
> 
> Note that the list was based on there being no defined semantics
> for the term in the MT, even if there might be range, domain,
> type, or other assertions made about the terms. The list (or the MT)
> may need adjusting if it is incorrect...
> 
> rdf:li was not mentioned in the MT, but that may be an omission
> since it's in the syntax doc. It is included in the list
> below.
> 
> --
> The RDF/S vocabulary includes several terms the meaning of which
> was undefined or ambiguous in earlier specifications of RDF and
> which remain undefined in the present RDF MT.
> 
> Specifically:
> 
>    rdf:value
>    rdf:Bag
>    rdf:Seq
>    rdf:Alt
>    rdf:li
>    rdf:_n
>    rdf:List
>    rdf:first
>    rdf:rest
>    rdf:nil
>    rdfs:comment
>    rdfs:seeAlso
>    rdfs:isDefinedBy
>    rdfs:label
> 
> These terms remain in the RDF/S vocabulary for various historical
> reasons. Their lack of an explicit or clear interpretation has
> resulted in their being used in incompatable ways by different
> applications. Nevertheless, as they provide utility to certain
> RDF applications, and in the interest of backwards compatability,
> they have not been deprecated or removed.

I suspect a reader familiar with M&S would think many of these terms
*did* have a clear and explicit interpretation.  In some cases we've
backed off from what was said in M&S.  In other cases, the problem was
the lack of a *machine-interpretable* interpretation.

> 
> Note that some of these terms do have certain constraints defined
> in the MT for their use, such as their domain, range or type, but
> their actual meaning is not specified.
> 
> Users should take care when employing these terms, as there is no
> guaruntee that any RDF applications will interpret them as intended.
> It should also be noted that no valid inferences may be drawn from
> statements using these terms, insofar as the model theory is concerned.
> Any interpretation or inference based on these terms is entirely
> application specific.

Can we explain this without references to "inferences"?  As valuable as
the concept is, at this point I'd just as soon not get into explaining
in the Primer what "inferences" have to do with anything if I can help
it.

--Frank


-- 
Frank Manola                   The MITRE Corporation
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Received on Monday, 9 December 2002 13:44:37 EST

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