title: OWL: abstract class implementation with ObjectUnionOf  seems failing hermiT, protégé
body: <p>Assuming GeographicArea as union of Planet, Continent and Region:</p>
  
  <blockquote>
  <pre><code>&lt;EquivalentClasses&gt;
      &lt;Class IRI="#GeographicArea"/&gt;
      &lt;ObjectUnionOf&gt;
          &lt;Class IRI="#Continent"/&gt;
          &lt;Class IRI="#Planet"/&gt;
          &lt;Class IRI="#Region"/&gt;
      &lt;/ObjectUnionOf&gt;
  &lt;/EquivalentClasses&gt;
  </code></pre>
  </blockquote>
  
  <p>then there should not be any individual of class GeopgraphicArea</p>
  
  <pre><code>&lt;ClassAssertion&gt;
      &lt;Class IRI="#GeographicArea"/&gt;
      &lt;NamedIndividual IRI="#Bad"/&gt;
  &lt;/ClassAssertion&gt;
  </code></pre>
  
  <p>Bad is obviously NOT a continent, planet or region.</p>
  
  <p>nevertheless hermiT reasoner  n Protégé does not report an error.</p>
  
  <p>Why?
  How could I restrict that no individual could be stated as "GeographicArea" only?</p>
  
  <p>See sample in: <a href="http://www.arcdev.hu/test/helloworld.owl" rel="nofollow">http://www.arcdev.hu/test/helloworld.owl</a></p>