Re: basic decisions underlying DAML-ONT (defined classes)

From: Dan Connolly <connolly@w3.org>
Subject: Re: basic decisions underlying DAML-ONT (defined classes)
Date: Thu, 12 Oct 2000 09:02:59 -0500

> "Peter F. Patel-Schneider" wrote:
> 
> >  For example, I would like to know
> > whether there is a basic decision in DAML-ONT to not allow necessary and
> > sufficient conditions for classes.
> 
> No... I/we just punted for lack of inspiration.
> 
> I tried, for maybe 10 minutes, to design such an idiom,
> and then gave up, since all the designs that occured
> to me involved ugly reification/quoting idioms. And this
> was before I had decided to go beyond RDF 1.0 with a simplified
> list/collection syntax.
>
> Dan Connolly, W3C http://www.w3.org/People/Connolly/

Why not create a new kind of object, perhaps called a description, which
would ``contain'' restrictions and qualifications.   The meaning of a
description would be the intersection of these restrictions and
qualifications.  A class could then be defined as ``equivalentTo'' to a
description.

Note that I am not proposing this as the best way of proceeding, just that
it would not be a major syntactic change to DAML-ONT.

Peter Patel-Schneider