Re: OWL Lite or DL?

Hi Chimezie --

Thanks for your most helpful posting.

At 01:00 PM 8/22/2006 -0400, you wrote:

>Actually, I believe by virtue of being of the SHOIN family of Description 
>Logics [1] that OWL-DL & RDFS can express this [transitive over] through 
>role hierachies and transitive roles

So, does it remain true that OWL by itself, without the help of RDFS, 
cannot express "transitive over" ?


>(both of which are part of [2] SHOIN: S - Role transitivity, H - Role 
>hierarchy)
>
>[1] http://www.cs.man.ac.uk/~horrocks/Publications/download/2003/HoPH03a.pdf
>[2] http://www.cs.man.ac.uk/~ezolin/logic/complexity.html
>
>I.e., instead of
>
>:worksFor :transitiveOver :consistsOf.
>
>you would have
>
>:consistsOf rdf:type owl:TransitiveProperty
>:worksFor rdfs:subPropertyOf :consistsOf
>
>Which would result in the same conclusions via a reasoner


I'd like to try this in practice.  Can you suggest some reasoners?

>following the axiomatic semantics of owl:TransitiveProperty and 
>rdfs:subPropertyOf (in N3):
>
>{?P a owl:TransitiveProperty. ?X ?P ?O. ?S ?P ?X} => {?S ?P ?O}.
>{?P rdfs:subPropertyOf ?R. ?S ?P ?O} => {?S ?R ?O}.

I hope to see this working.  But even if it does, I'm concerned that 
extending this kind of notation beyond toy problems is going to result in 
reasoning that is very hard to check. To put it another way, the logic is 
very powerful, and the notation is somewhat opaque, so that a small slip in 
writing is easy to make and could have vast erroneous consequences -- 
particularly if deployed over the world wide web.

Hope I'm wrong about this.  What do you think?

                                 Cheers,   -- Adrian



Internet Business Logic (R)
Executable open vocabulary English
Online at www.reengineeringllc.com
Shared use is free

Adrian Walker
Reengineering
PO Box 1412
Bristol
CT 06011-1412 USA

Phone: USA 860 583 9677
Cell:    USA  860 830 2085
Fax:    USA  860 314 1029

Received on Tuesday, 22 August 2006 22:28:36 UTC