Classes and predicates as first class objects

 Much of the debate around layering of OWL on top of RDF and RDFs boils 
down to whether the Semantic Web should treat classes and arc labels as 
first class objects, about which arbitrary new kinds of statements can 
be made.

This is an important architectural choice which has to take into account 
results from systems that have been built. Looking at what was learnt 
from such systems would probably be productive ...

 RDF, which has been largely influenced by the experimental "scruffy" 
side of AI has gone the route of many experimental AI systems (starting 
from KRL, RLL, .... CycL) and incorporated these as first class objects. 
In my experience, and the experience of the builders of these systems, 
this has been a useful feature. Description Logics, which come from the 
more "neat" side of AI chose not to allow this ...

Clearly, not allowing this feature buys description logics something. 
Ian, maybe you could explain exactly what this is and how it has been 
found useful in large DL systems that have been built?

thanks,

guha

Received on Wednesday, 14 August 2002 17:21:31 UTC