text: 4. Look at the check boxes on the right under Query for. Check Superclasses, Subclasses (although it 
  should already be checked by default) and Instances. Now your UI should look like figure 9.1. You may 
  notice that owl:Nothing shows up as a subclass. Don’t worry that is actually expected. Remember that 
  owl:Nothing is the empty set and the empty set is a subset of every set (including itself) so just as 
  owl:Thing is a superclass of every class owl:Nothing is a subclass of every class. If you don’t want to 
  see owl:Nothing you can uncheck the box toward the bottom right that says Display owl:Nothing. 
  
  5. Try some additional DL queries such as: hasTopping some (hasSpiciness value Hot) and 
  VegetarianPizza and (hasTopping some (hasSpiciness some (isMilderThan value Hot))). Note that with 
  this last query you are taking advantage of the transitive order you defined for the instances of the 
  Spiciness class in chapter 6. 
  
  6. You can also do queries for strings in the names of your entities. For example, first do a query simply 
  with Pizza in the query window. Then type in Hot in the Name contains field. This should give you all the 
  classes and individuals with*Hot*in their name. 