Harold Boley suggested in the IRC channel using an extension of CARIN-ALLNR.
Ian noted that we need to investigate more to determine if the combined language is in fact less than FOL. We don't want to spend lots of effort reinventing FOL.
Pat Hayes asked for a definition of "rule" as used in this proposal. ACTION (Benjamin): provide a definition of "rule"
Horn axioms (conjunctive premise in body, conclusion in head) are the point of departure. Some other constructs are expressively reducible.
More rule examples would be desirable. Richard offered to identify Ontolingua ontologies that include axioms.
Stanford KSL has a strawman query proposal in-house. The premise is a DAML+OIL knowledge base. The query consists of DAML+OIL statements + variables. ACTION (Richard): distribute this proposal to joint-committee@daml.org.
Pat opined that while we'd like to find a natural way to fit query and rules together, convergence is desirable, but non-convergence wouldn't be fatal.
Lynn noted that non-convergence could be a problem, e.g. if the query
language was more powerful than the rule language.
Ian gave the example that you can't currently express uncle
(based on brother and child)
in DAML+OIL.
Pat suggested that query processing should involve entailment.
There was some discussion of handling of unnamed individuals. Deb addressed this problem in her thesis work with Borgida. She also referred people to a paper Asking Queries about Frames.
There was some discussion of a staged approach. Ben suggested that we start with subsumption and existence and build from there. It may make sense to release an Interim Query Language for querying current DAML+OIL knowledge bases, and extend this to support rules later.
We should be at least "mutually aware" of related efforts including RQL, SquishQL, and XQL. There was a RDF Query BOF at SWWS that included 5 proposals.
W3C basically wants to ensure that the material will be freely usable by it and other organizations. It doesn't require transferring the copyright to W3C (like a journal publication). Folks/organizations joining WebOnt will have to relinquish or declare any existing Intellectual Property rights, so they're presumably already covered.
Ian suggested just making DAML+OIL public domain or releasing it under terms such as the GNU Public License (GPL).
ACTION (Mike): reply to the W3C folks and ask what else we need to do
Ian and others noted that we need a useful interaction between the rule and query languages, and that this is a good place to do it.
Please let Mike know if you'd like to take this opportunity to gracefully resign from the Joint Committee.
It was previously suggested that we add a member of the DAML-S Coalition to the Joint Committee. Rather than picking someone ourselves, we'll ask the DAML-S folks to suggest a liaison with their group. ACTION (Mike): contact the DAML-S folks.
We'll plan to have a group vote next week on inviting Benjamin Grosof, Richard Fikes, Harold Boley, and a DAML-S representative (if named) to officially join the Joint Committee. Please send any negative votes or other concerns to Mike beforehand.
subClassOf/subPropertyOf
feedback to
RDF Core
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