Re: Classes and predicates as first class objects

On August 15, Jim Hendler writes:
> 
> At 9:42 PM +0100 8/15/02, Ian Horrocks wrote:
> >
> >
> >Work on DLs has resulted in the development of a family of logical
> >languages with precisely defined semantics and well understood
> >computational properties. They are (almost invariably) decidable
> >subsets of FOL and are closely related to propositional modal and
> >dynamic logics.  For many of these languages, provably sound and
> >complete decision procedures have been devised. Several DL systems
> >have been based on optimised implementations of these algorithms, thus
> >providing users with reasoning services that are both reliable and
> >efficient. These systems are being used in a wide range of
> >applications, e.g., in medical-informatics, bio-informatics, chemical
> >engineering and geographical information systems.
> >
> >Ian
> 
> I don't debate a word of that, but which of those things do you 
> believe to be unique to DLs?

Probably none. As I mentioned above, DLs are decidable fragments of
FOL and have much in common with propositional modal and dynamic
logics, and these logics may share similar properties (although DL
research has probably been more focused on optimised
implementation). It wasn't me that brought up the subject of DLs - I
was just answering a question about them.

Ian


>   -JH
> 
> -- 
> Professor James Hendler				  hendler@cs.umd.edu
> Director, Semantic Web and Agent Technologies	  301-405-2696
> Maryland Information and Network Dynamics Lab.	  301-405-6707 (Fax)
> Univ of Maryland, College Park, MD 20742	  240-731-3822 (Cell)
> http://www.cs.umd.edu/users/hendler

Received on Thursday, 15 August 2002 19:20:02 UTC