Relation owl#same_as (?,?)  MORE PRECISE TYPES THAN THIS ONE SHOULD BE USED
  supertype:  pm#equal (pm)  "=" in KIF; true if the 1st argument is identical to the 2nd
  equal:  daml#equivalent_to (owl)
  subtype:  pm#same_type_as (pm#type,pm#type)
     subtype:  owl#equivalent_class (rdfs#class,rdfs#class)  in WebKB, use the link '='
     subtype:  owl#equivalent_property (pm#binary_relation_type,pm#binary_relation_type)  in WebKB, use the link '='
  subtype:  owl#same_individual_as (?,?)