[Pellet-users] Open world reasoning with quantifiied restrictions

[John M. Linebarger]

Hello!  I posted a variant of this question a year or so ago, but now I am giving a talk at the Semantic Technologies 2007 conference and I need to understand the details of what is going on.  I am using Pellet 1.4 with Jena 2.5.2.
I have a small paedogogical ontology I call the Jabberwocky ontology, which I use to demonstrate the value of Semantic Technologies to new audiences.  Essentially, I have created an ontology around Lewis Carroll's Jabberwocky poem, and marked up the nonsense words with parts of speech and positive/negative connotations.  I also have a SPARQL query that creates sentences with positive or negative connotations, Madlibs-style, using randomly chosen words from either the Jabberwocky or the Scots dialect of English.
My problem occurs when I try to create a class called "ImpoliteWord" and have the reasoner assign words to that class.  My first naive approach was to say that an ImpoliteWord was a word that had negative connotations but no positive connotations (hasNegativeConnotations has "yes" AND hasPositiveConnotations exactly 0).  However, no words were ever assigned by the reasoner to that class.  When I posted this question a year ago, the answer came back that I had violated the open world assumption, since there was no way to know if hasPositiveConnotations would ever be exactly 0.  
I think I understand that, but I have two additional questions.  First, is there another way to approach this problem in OWL such that I achieve the result that I want?  And second, what is the purpose of quantified restrictions in the first place?  It would seem that all such quantified restrictions would run afoul of the open world assumption, such that they would be useless from a reasoning point of view.
Here is the RDF/XML for the "ImpoliteWord" class that does not work:
  <owl:Class rdf:ID="ImpoliteWord">
    <owl:equivalentClass>
      <owl:Class>
        <owl:intersectionOf rdf:parseType="Collection">
          <owl:Restriction>
            <owl:cardinality rdf:datatype="http://www.w3.org/2001/XMLSchema#int"
            >0</owl:cardinality>
            <owl:onProperty>
              <owl:DatatypeProperty rdf:about="#hasPositiveConnotation"/>
            </owl:onProperty>
          </owl:Restriction>
          <owl:Restriction>
            <owl:onProperty>
              <owl:DatatypeProperty rdf:about="#hasNegativeConnotation"/>
            </owl:onProperty>
            <owl:hasValue rdf:datatype="http://www.w3.org/2001/XMLSchema#string"
            >yes</owl:hasValue>
          </owl:Restriction>
          <owl:Class rdf:about="#Word"/>
        </owl:intersectionOf>
      </owl:Class>
    </owl:equivalentClass>
  </owl:Class>
Many thanks!
John M. Linebarger, PhD
Sandia National Laboratories
Albuquerque, New Mexico, USA
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