- From: Patrick Stickler <patrick.stickler@nokia.com>
- Date: Thu, 20 Jun 2002 10:19:47 +0300
- To: RDF Core <w3c-rdfcore-wg@w3.org>
I just wanted to toss the following comment out, which I didn't get an opportunity to do during the f2f when discussing the relationships between terms, statements, vocabularies and schemas. It was suggested that all that was needed was the relationship between term and schema, and that if an application needed to know what statement was said about the term by a given schema, then it could go look at the RDF/XML of that schema itself. I consider that to be an unacceptable requirement on the application and if done, to be unacceptable behavior by the application. If there is knowledge present in an RDF/XML schema that is intended to be visible to some RDF application, such as the provenance of a given statement per a particular schema, and that knowledge is not carried over into the graph, then that is a bug (of some sort). If it's not in the graph, it doesn't exist. RDF applications should *not* go back to the RDF/XML serializations to try to grok knowledge that is not explicit in the graph. The parsing of RDF/XML into triples defines *all* of the knowledge that a given RDF application is licensed to consider, and if a conformant parser has not generated a given triple itself, then the application should *not* infer that triple from the RDF/XML serialization separately. Thus, if specific statements must be associated with specific schemas where they are expressed, then the mechanisms provided by RDF to do so must be used -- namely reification. If each statement in a schema is not explicitly reified with an rdfs:isDefinedBy qualification pointing to that schema, and all that is provided are rdfs:isDefinedBy qualifications for terms, then *all* that can be known by a given application is that the schema says *something* about the term, but it can never know exactly *what* is said about the term. Cheers, Patrick -- Patrick Stickler Phone: +358 50 483 9453 Senior Research Scientist Fax: +358 7180 35409 Nokia Research Center Email: patrick.stickler@nokia.com
Received on Thursday, 20 June 2002 03:32:55 UTC