Rdf Primer / quote 20 of 55
No locally different ranges in RDF Schema
Another result of the global scope of RDF property descriptions is that it is not possible in an RDF schema to define a specific property as having locally-different ranges depending on the class of the resource it is applied to. For example, in defining the property ex:hasParent, it would be desirable to be able to say that if the property is used to describe a resource of class ex:Human, then the range of the property is also a resource of class ex:Human, while if the property is used to describe a resource of class ex:Tiger, then the range of the property is also a resource of class ex:Tiger. This kind of definition is not possible in RDF Schema. Instead, any range defined for an RDF property applies to all uses of the property, and so ranges should be defined with care. However, while such locally-different ranges cannot be defined in RDF Schema, they can be defined in some of the richer schema languages..