Re: decisions at recent RDF Core WG F2F

At 18:36 15/07/2002 -0400, Peter F. Patel-Schneider wrote:

>I note that a decision in the recent RDF Core WG F2F states that the
>value (I assume object is meant here) of an rdfs:isDefinedBy statement can
>be ``any document or resource''.
>What does this mean?

The WG considered introducing a class which might have been called 
rdfs:Schema and constraining the range of rdfs:isDefinedBy to that 
class.  It chose not to do so and hence this statement should be read as 
the range of rdfs:isDefinedBy is rdf:Resource.

>   Is it an official statement by the RDF Core WG that
>there are other things besides resources?


>If so, when will the model
>theory be revised?  What status will documents have in RDF?

No major revisions to the model theory are required for this decision.

>It appears that the RDF Core WG is edging towards a two-semantics
>approach.  This approach has caused considerable problems for DAML+OIL.
>Perhaps it would be a good idea to solicit advice here.

I take it you are referring to describing the semantics of RDF(S) in 
LBase.  The current position is that the semantics of RDF(S) will be 
defined by the model theory.  The semantics document will contain a 
non-normative appendix describing the semantics in terms of LBase on the 
grounds that this will be easier for those less familiar with model theory 
to follow.

LBase is a proposal for specifying the semantics of several semantic web 
languages.  I have argued that the suitability of this approach must be 
discussed in a wider forum than RDFCore and I hope such a forum will be 
found/created soon.  I have argued this in part so that you will be able to 
influence that decision.

Regarding advice, I hope Peter, that you don't feel you need of an 
invitation to warn us when you think we may be making a misstep.  If you 
wish to offer some observations, or suggest someone we should approach for 
input, please feel free at all times to do so.

And in this particular case, what is it that you feel we ought to know?

>I also note that a decisions includes the wording
>         A statement with a property ...
>This appears to be a *major* change to RDF, as previously statements could
>not have properties.  Of course, this probably should read
>         A statement whose predicate ...
>:-)  (last point only, to be clear)

Thank you for that.  I'm glad you were not misled by the poor wording.


Received on Tuesday, 16 July 2002 10:47:54 UTC