- From: pat hayes <phayes@ai.uwf.edu>
- Date: Fri, 13 Jul 2001 11:34:02 -0700
- To: jos.deroo.jd@belgium.agfa.com
- Cc: w3c-rdfcore-wg@w3.org
>[...]
> > > based on what we have testcased at
> > > http://www.agfa.com/w3c/euler/#Problem
> > > I completely agree with you and I really
> > > wonder how else we could model/infer
> > > http://www.agfa.com/w3c/euler/tpoint-result.n3 or
> > > http://www.agfa.com/w3c/euler/tpoint-all.n3
> >
> > The answer is that in RDF, you *can't* infer this stuff.
> >
> > You use N3, which is way more expressive than RDF; it has negation
> > and universal quantifiers, just for a start.
>
>Fine, but per http://www.w3.org/2000/10/swap/log#
>and e.g. http://www.w3.org/2000/10/swap/model.n3#
>one *can* produce/consume regular N-Triples, no?
Yes and no. They do produce triples, but how are those triples
interpreted? If they are interpreted using the meanings suggested by
the M&S (I refrain from saying 'semantics') then you can't validly
infer this stuff. Cwm infers it by imposing some extra
interpretations on the triples, ie in effect treating them as
triple-encodings of expressions in some other language, which as far
as I know has never been precisely defined anywhere, though it seems
to be something close to prolog with a nonstandard negation (? A
guess, as the only way to know for sure is to inspect the Cwm code
and reverse-engineer the intended semantics.).
http://www.w3.org/2000/10/swap/log# pretty much says this directly, eg:
-------------
log:N3Document a rdfs:Class;
rdfs:comment """A document which, which parsed as Notation3
as defined in general by http://www.w3.org/DesignIssues/Notation3.html
and this schema, conveys the intent of the author by the semantics defined
on those specifications, and the semantics defined by the specifications
of any identifiers used in the document.
""" .
log:implies a rdfs:Property;
rdfs:comment "Logical implication. Understood natively by cwm.";
rdfs:range log:Formula;
rdfs:range log:Formula.
log:resolvesTo a rdf:Property;
rdfs:domain doc:Work;
rdfs:range log:Formula;
rdfs:label "forumla";
rdfs:comment """This connects a document and the formula it parses to.
Cwm knows how to go get a document and parse it in order to
evaluate this.""".
----------------
Notice in the last two cases the explicit reference to Cwm's 'native'
ability to interpret something that is not defined in RDF.
Pat Hayes
---------------------------------------------------------------------
(650)859 6569 w
(650)494 3973 h (until September)
phayes@ai.uwf.edu
http://www.coginst.uwf.edu/~phayes
Received on Friday, 13 July 2001 14:34:04 UTC