W3C home > Mailing lists > Public > www-webont-wg@w3.org > February 2002

Re: UPDATE: longer version of layering document

From: Peter F. Patel-Schneider <pfps@research.bell-labs.com>
Date: Sat, 09 Feb 2002 07:43:33 -0500
To: jos.deroo.jd@belgium.agfa.com
Cc: www-webont-wg@w3.org
Message-Id: <20020209074333F.pfps@research.bell-labs.com>
From: "Jos De_Roo" <jos.deroo.jd@belgium.agfa.com>
Subject: Re: UPDATE: longer version of layering document
Date: Sat, 9 Feb 2002 11:03:34 +0100

[...]

> Sure.
> Having :s :p [ :a :b ] . (which is N3's way
> to write :s :p _:o . _:o :a :b)
> then there is *no* way to point to that [ :a :b ].
> You can however use that [ :a :b ] ``by-value'' i.e.
> make a ``copy'' of [ :a :b ] e.g. :x :y [ :a :b ] .
> (after all, bnodes are untidy anyway)

Sure you *can* do this, but what is the point?  Are you saying that Bnodes
should only have one incoming edge?  If so, then you should speak *very*
quickly to the RDF Core WG.  I'm only using the facilities available in
RDF.

> So [the acyclic and?] cyclic cases are ruled out that
> way and you basically get a ``tree'' where
> the leaves are urirefs or literals and the
> bnodes are ``branches''.
> That's the way we do things in Euler, and believe
> me, we have no trouble with such cases.

Well then Euler cannot handle all of RDF.  Are you sure you want this?

> (Remembering the
> :John a [ owl:intersectionOf ( :Student :Person ) ] .
> entailing
> :John a [ owl:intersectionOf ( :Person :Student ) ] .
> using
> http://www.agfa.com/w3c/euler/owl-rules.n3)


The problem is that we have an already-exisiting formalism to deal with.
(Yes, of course, it is under change, but only in certain, limited ways.)
If our solution to problems posed by characteristics of that formalism is
to change the formalism, then we need to be very clear as to what changes
we want to pose, why we want to pose them, and what result we want.


As an aside, I believe that I have made my views on what changes I want to
RDF and RDFS clear.  (For a recap, with some additions, see below.)  How
about let's propose them to the RDF Core WG?


> --
> Jos

Peter F. Patel-Schneider

PS:  Here are (most of) my proposed changes to RDF:
1/ Move rdf:type out of the theory into the metatheory
2/ Remove reification.
3/ Remove containers.
4/ Remove several syntax abbreviations.
I want 2 and 3 removed because they don't have appropriate meaning. I want
4 removed because it interferes with the correspondence between RDF and
XML. I want 1 moved because it causes semantic paradoxes in more-powerful
formalisms. 
Received on Saturday, 9 February 2002 07:43:49 GMT

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