Relation pm#relation_from_attribute_type (attribute_class,*)
  supertype:  relation_from_class
  subtype:  contrary_attribute (attribute_class,attribute_class+)  set of attributes such that something can not simultaneously have more than one of these attributes, e.g., in KIF, (sumo#contrary_aAttribute sumo#pliable sumo#rigid) means that nothing can be both pliable and rigid
  subtype:  exhaustive_attribute (attribute_class,attribute_class+)  this predicate relates a class to several types of attributes, and it means that the elements of this set exhaust the instances of the class; for example, in KIF, (sumo#exhaustiveAttribute sumo#physicalState sumo#solid sumo#fluid sumo#liquid sumo#gas) means that there are only three instances of the class sumo#physicalState, viz. sumo#solid, sumo#fluid, sumo#liquid, and sumo#gas