Re: Recursive axioms in OWL DL from Peter F. Patel-Schneider on 2005-06-04 (public-owl-dev@w3.org from April to June 2005)

From: Peter F. Patel-Schneider <pfps@research.bell-labs.com>
Date: Sat, 04 Jun 2005 10:24:03 -0400 (EDT)
To: leonardi@cs.unibo.it
Cc: public-owl-dev@w3.org
Message-Id: <20050604.102403.04536301.pfps@research.bell-labs.com>

From: Andrea Leonardi <leonardi@cs.unibo.it>
Subject: Recursive axioms in OWL DL
Date: Sat, 4 Jun 2005 02:39:22 +0200 (CEST)

> 
> Hi,
> 
> I just wanted to know whether the constraint
> 
>    "All axioms must be well-formed, with no missing or
>     extra components, and must form a tree-like structure"
>    (OWL Web Ontology Language Reference, sec. 8.2)
> 
> implies that the TBox of an OWL DL application
> (seen as a Description Logic) must NOT be cyclic.
> 
> Thanks in advance,
> Andrea

No it doesn't.  

I hadn't thought that it could be misinterpreted that way, but, upon
further reflection, I can see where this reading might creep in.

What is forbidden is a description that refers directly back to itself.

Peter F. Patel-Schneider

Received on Saturday, 4 June 2005 14:24:16 UTC