Re: OWL lite and intersectionOf

From: Stefano David <sdavid@delicias.dia.fi.upm.es>
Subject: OWL lite and intersectionOf
Date: Thu, 15 Jun 2006 14:55:11 +0200

> 
> Hello,
> I have a (perhaps) stupid question, however I can not find out any answer....
> 
> I know it is possible to express in OWL Lite that a class can be defined 
> as the (subclass of) an intersection of two or more other classes (which 
> is the case I am interested in), but this fact is not reflected in the 
> OWL Lite abstract syntax. What it is possible to find is the OWL DL axiom :
> 
> description ::= classID
>             | restriction
>             | 'unionOf(' { description } ')'
>             | 'intersectionOf(' { description } ')'
>             | 'complementOf(' description ')'
>             | 'oneOf(' { individualID } ')'
> 
> but there is no "description" in any OWL Lite axiom (not at [1], at least).
> Hence, there is something I am missing. I tried to figure out what a 
> possible axiom for generating intersectionOf (in OWL Lite) might be:
> 
> super :: = classID | restriction | 'intersectionOf(' class ID { classID 
> } {restriction}')'

> Questions are: am I correct? Or where is the point I am missing?

You are close, but not quite right.

There is an implicit intersection in the class definition axiom: 

axiom ::= 'Class(' classID ['Deprecated'] modality { annotation } { super } ')'

The new class is equivalent or a sub-class of the intersection of the
supers.  This means that no separate intersection construct is needed.

> Thanks for the attention,
> Stefano David
> 
> [1] http://www.w3.org/TR/owl-semantics/

Peter F. Patel-Schneider

Received on Thursday, 15 June 2006 14:33:20 UTC