riple, 
<i>subject/predicate/object</i>, is a basic manner in constructing ontology in 
RDF. It implies that SWCLOS must add a slot value without the slot definition in 
the class. Therefore, SWCLOS enabled the piecewise slot addition for objects. 
Furthermore, the capability for forward referencing is required. Namely, SWCLOS 
must be able to accept undefined classes and instances as referent. Fortunately 
we have the principle of monotonicity in Semantic Webs and many entailment rules 
in RDF, RDFS and OW