In OWL Full all data values are considered also to be part of the individual
domain. In fact, in OWL Full the universe of individuals consists of all
resources (owl:Thing is equivalent to rdfs:Resource).
Two OWL class identifiers are predefined, namely the classes owl:Thing
and owl:Nothing.
The class extension of owl:Thing is the set of all individuals. The
class extension of owl:Nothing is the empty set. Consequently,
every OWL class is a subclass of owl:Thing and
owl:Nothing is a subclass of every class.
<Class rdf:ID="Thing">
<rdfs:label>Thing</rdfs:label>
<unionOf rdf:parseType="Collection">
<Class rdf:about="#Nothing"/>
<Class>
<complementOf rdf:resource="#Nothing"/>
</Class>
</unionOf>
</Class>
<owl:Class>
<owl:oneOf rdf:parseType="Collection">
<owl:Thing rdf:about="#Eurasia"/>
<owl:Thing rdf:about="#Africa"/>
<owl:Thing rdf:about="#NorthAmerica"/>
<owl:Thing rdf:about="#SouthAmerica"/>
<owl:Thing rdf:about="#Australia"/>
<owl:Thing rdf:about="#Antarctica"/>
</owl:oneOf>
</owl:Class>
The RDF/XML syntax <owl:Thing rdf:about="..."/> refers to
some individual (remember: all individuals are by definition instances of
owl:Thing).
The class with identifier owl:Thing is the class of all individuals, and is part of OWL Lite.