LANG: PrimitiveClass, DefinedClass

The annotated OWL language description (2 april) contains several options 
for replacing
the uninformative and to many people unclear names PrimitiveClass and 
DefinedClass.
I would like to add one.

The main requirement on new names for these primitives seems to be
that these names are, perhaps after having been explained once, largely 
self-explanatory to the largest 
possible group of people, and that no separate mnenomic is needed.
We should preferably not make an assumption about any other field (e.g. 
mathematics: necessary/
sufficient conditions; or terminology from object-oriented modeling/UML)

The following proposal seems to satisfy this requirement:

Instead of DefinedClass:
ExactClass ( <classID> , <supers>, <slots> )

Instead of PrimitiveClass:
ContainedClass ( <classID> , <supers>, <slots> )

That is, a class defined by means of ExactClass is exactly the 
intersection of the superclasses
in its definition and the (classes defined by its) slot constraints.

A class defined by means of ContainedClass is contained in the 
intersection of the superclasses
in its definition and the (classes defined by its) slot constraints.

The illustration above involves the core version of OWL.  Of course, the 
terminology also applies
to the full version.

Herman ter Horst
Philips Research