- From: Peter F. Patel-Schneider <pfps@research.bell-labs.com>
- Date: Thu, 30 May 2002 11:03:19 -0400
- To: connolly@w3.org
- Cc: phayes@ai.uwf.edu, danbri@w3.org, www-rdf-logic@w3.org
From: Dan Connolly <connolly@w3.org> Subject: Re: MISC: Internet Media Type registration: proposed TAG finding Date: 30 May 2002 09:05:20 -0500 > On Thu, 2002-05-30 at 08:28, Peter F. Patel-Schneider wrote: > > From: Dan Connolly <connolly@w3.org> > > Subject: Re: MISC: Internet Media Type registration: proposed TAG finding > > Date: 29 May 2002 20:27:11 -0500 > > > > > On Fri, 2002-05-24 at 23:05, Peter F. Patel-Schneider wrote: > > > > [...] > > > > > > But according to your rules, any method of providing meaning for this > > > > extension is adequate. > > > > > > No, only those that are monotonic. i.e. when you specify an extension, > > > you can only throw out models; you can't put any back in. > > > > > > > OK, the method that I will use is that it means > > > > what I mean it to mean. > > > > > > So long as it's monotonic, then you haven't provided an example > > > that ... > > > > Suppose we have > > > > <ex:John> <ex:loves> <ex:Mary> . > > > > <_:s1> <rdf:type> <rdf:Statement> . > > <_:s1> <rdf:subject> <var:?x> . > > <_:s1> <rdf:predicate> <ex:loves> . > > <_:s1> <rdf:object> <var:?y> . > > > > <_:s2> <rdf:type> <rdf:Statement> . > > <_:s2> <rdf:subject> <var:?a> . > > <_:s2> <rdf:predicate> <var:?b> . > > <_:s2> <rdf:object> <var:?c> . > > > > <_:s1> <log:implies> <_:s2> . > > > > The non-RDF part of this document, i.e., the meaning of log:implies as a > > form of logical implication, completely changes the meaning of foo:loves. > > No, there are no more models in a theory that include a > specification of log:implies than there are in a theory > that just treats log:implies as a plain RDF predicate. > > I'm not sure what you mean by "the meaning of <a term>", > nor "completely changes the meaning of <a term>". > > Going back a bit to your message of 23 May 2002 20:14:13 -0400, > you said: > > PFPS> so the partial understanding may not be related to the ``real'' > PFPS> meaning in any worthwhile fashion. > > to which I replied, 23 May 2002 22:08:16 -0500: > > DC> it's monotonic, in that the more you understand, the fewer > DC> interpretations are models. You can't rule out models by > DC> failing to understand something. > > The example above is not a counterexample of this claim > that partial understanding is monotonic. So you claim. The RDF meaning of log:implies includes lots of interpretations where the implication does not hold. The extended meaning incorporates only those where the implication does hold. This completely changes the meaning of log:implies, changing it from an uninterpreted property to a logical connective. > -- > Dan Connolly, W3C http://www.w3.org/People/Connolly/ Peter F. Patel-Schneider
Received on Thursday, 30 May 2002 11:04:14 UTC