Re: "meaningless terms" verbage for Primer

[Patrick Stickler, Nokia/Finland, (+358 40) 801 9690, patrick.stickler@nokia.com]


----- Original Message ----- 
From: "ext Frank Manola" <fmanola@mitre.org>
To: "Patrick Stickler" <patrick.stickler@nokia.com>
Cc: "w3c-rdfcore-wg" <w3c-rdfcore-wg@w3.org>
Sent: 09 December, 2002 20:43
Subject: Re: "meaningless terms" verbage for Primer


> 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.  

Then we need to say where we've backed off from M&S.

> In other cases, the problem was
> the lack of a *machine-interpretable* interpretation.

Hmmmm.... isn't that the only point to RDF? Enabling *machines*
to do something useful with our content?

If there is no machine interpretable interpretation, then IMO
there is no interpretation whatsoever. Eh?

> > 
> > 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.

Fine. I stole that from comments made by Pat. The key point is that
users should not expect RDF applications to do anything consistently,
or anything at all, based on those terms as their interpretation is
always application specific, if any interpretation occurs at all.

Human intuition about what the natural language mnemonics of the
terms suggests has no normative weight here, and folks are free
to use the terms in whatever way they choose without violating
the RDF specs in any way.

In short: here be dragons...

Cheers,

Patrick

Received on Tuesday, 10 December 2002 05:08:57 UTC