Re: Help Required

On 29 Jul 2009, at 10:49, Muhammad Javed wrote:

> Hi,
>
> I would like to ask that
>
> 1_ How one can define Axioms.....
>
> Is it a part of Ontology ? OR
>
> Different Property Characteristics combine together and present an  
> axiom.

http://www.w3.org/TR/2009/CR-owl2-syntax-20090611/#Axioms

I would say that an axiom is a closed well formed formula.

> 1_ How one can define Ontology.
>
> Is it a tuple of C, P and I   OR
>
> It consist of C, P ,I Restrictions and Axioms...

http://www.w3.org/TR/2009/CR-owl2-syntax-20090611/#Ontologies

I would say, as a very first approximation, that an Ontology is a set  
of axioms.

It's a very first approximation because, for example, we can  
distinguish two ontologies by name, we can further distinguish them by  
a set of ontology annotations, and we can even further distinguish  
them by their imports substructure.

So, structurally, we can define an OWL ontology as:

	1) an object
	2) which has a (possibly empty) name slot)
	3) which has a (possibly empty) set of annotations
	4) that roots a (possibly empty) set of directly imported ontologies
	5) and contains a set of axioms (including declaration axioms)

Cheers,
Bijan.