# subClassOf inteferences (RDF and OWL)

## by Richard H. McCullough

For any two classes, x and y,
x subClassOf y
implies that either
x sameAs y
or
x properSubClassOf y
The distinction is important in making further inferences about x and y.

The revised .rdf files for RDF[1] and OWL[2] are given in [3] and [4], showing the true alternative for each case.

In summary:
all cases of subClassOf and subPropertyOf are properSubClassOf, except
Class sameAs Class

## References

[1] http://www.w3.org/TR/2003/WD-rdf-schema-20030123/
[2] http://www.w3.org/TR/2003/WD-owl-ref-20030331/
[3] RDF subClassOf inferences.rdf
[4] OWL subClassOf inferences.rdf