fre 2010-10-15 klockan 00:05 +0100 skrev Hogan, Aidan:
> +1 to what Mikael says below, except some minor (academic) issues:
>
> > The second says that all instances of AgentClass are also classes.
> That
> > is, the student Bob cannot be an AgentClass, but the class of Students
> > (of which Bob is one) can be an AgentClass.
>
> <nit-picking>
> Bob can be an AgentClass in either formal definition. Given "AgentClass
> rdfs:subClassOf rdfs:Class", it simply means that Bob can be inferred to
> be a class (as a side-effect, implicitly discouraging usage where Bob is
> intended to be an individual).
> </nit-picking>
Well, yes, I assumed disjointness between Agent and Class :-)
>
> > What remains to express is that all members of an instance of
> AgentClass
> > are Agents (equivalently: all instances of AgentClass are subclasses
> of
> > Agent). This isn't expressible in RDF Schema. And the notion is
> > incompatible with OWL DL, and requires OWL Full to be expressed...
>
> <moot-point>
> It should now be compatible with OWL 2 DL, given the inclusion of some
> meta-modelling support in OWL 2 [1].
> </moot-point>
Well, I haven't been following OWL2, but WOW, that's great news. There
are quite a few situations where that is a very natural thing to do.
/mikael
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