- From: Jos De_Roo <jos.deroo@agfa.com>
- Date: Thu, 22 Jan 2004 21:36:19 +0100
- To: Ian Horrocks <horrocks@cs.man.ac.uk>
- Cc: herman.ter.horst@philips.com, "Peter F. Patel-Schneider" <pfps@research.bell-labs.com>, www-webont-wg@w3.org
I can't find a problem with Herman's proposal but I can also follow your conclusions... I have no problem with the change for miscellaneous-205 (my implementation can't prove a consistency). My implementation also can't prove that :v :p "<"^^rdf:XMLLiteral. :p rdfs:range rdfs:Literal. is Full-inconsistent, but it can prove that :v :p "<"^^rdf:XMLLiteral. :p rdfs:range rdf:XMLLiteral. is Full-inconsistent. -- Jos De Roo, AGFA http://www.agfa.com/w3c/jdroo/ Ian Horrocks <horrocks@cs.man. To: herman.ter.horst@philips.com ac.uk> cc: www-webont-wg@w3.org, "Peter F. Patel-Schneider" Sent by: <pfps@research.bell-labs.com> www-webont-wg-req Subject: Re: XMLLiteral in OWL uest@w3.org 22/01/2004 18:24 Please respond to Ian Horrocks I believe that we should keep changes to an absolute minimum. I don't believe that the change proposed by Herman, or either of the first two changes proposed by Jeremy are necessary because they only aim to make explicit what is already implicit). I believe that we should make the third change proposed by Jeremy, i.e., to modify test miscellaneous-205 by deletion of the word "Full" from its levels box - this slightly weakens the test and alleviates the problem that it may really be incorrect in its current form. Ian On January 19, herman.ter.horst@philips.com writes: > > During the last telecon I was actioned with Jeremy and Ian > to look at the problem of XMLLiteral in OWL and propose > a decision [1]. > In this message I summarize the problem and the decision > that was already proposed during the meeting. > (See, e.g., [3-7] for earlier discussion about this problem.) > > Problem > - The OWL design allows the possibility of doing without > semantic conditions on XMLLiteral. This is visible in > the Test document (see tests 201-205). > - S&AS Section 5 (RDF-compatible model-theoretic semantics) > does not allow the possibility of doing without semantic > conditions on XMLLiteral. OWL Full interpretations as well > as OWL DL interpretations are D-interpretations (from the > RDF Semantics document) and thereby always incorporate > semantic conditions on XMLLiteral. > - This mismatch between S&AS and Test disturbs a bigger > point: as is described in the first paragraph of Test, > S&AS is the primary normative document about OWL, and > Test is a 'subsidiary' document, aiming to give examples > and clarification of S&AS. As I wrote earlier, > >If the document > >is left with an error like this, how can a reader decide > >for any statement of S&AS whether it is reliable? > > Example: the RDF graph > v p l > p rdfs:range rdfs:Literal > where l is an ill-typed XML literal, is DL and > Full-inconsistent according to S&AS Section 5, > whether the datatype map D contains XMLLiteral or not. > Test allows the possibility to not include XMLLiteral > in the datatype map, in which case this RDF graph > becomes consistent for DL or Full. > > == > > Proposed solution: > > incorporate the three changes precisely described in > Jeremy's note "possible compromise on rdf:XMLLiteral" [2] > *and* add one sentence to S&AS Section 5 following > the sentence just before Section 5.1: > "If, however, any conflict should ever arise between > these two forms, then the Direct Model-Theoretic > Semantics takes precedence." > The new sentence following this sentence should express > that this applies (so that the direct semantics takes > precedence) when XMLLiteral is not in the datatype map. > > (To summarize, the three changes described by Jeremy in [2] > ensure that > -an OWL interpretation (S&AS Section 5.2) always assumes > XMLLiteral in its datatype map (not mentioning this > would misleadingly suggest that this is not necessary) > -the datatype map for OWL Full always includes XMLLiteral > -Test 205 does not apply to OWL Full.) > > During the last telecon support for this solution was expressed > by Jeremy and me. > > > Herman > > [1] http://lists.w3.org/Archives/Public/www-webont-wg/2004Jan/0040.html > [2] http://lists.w3.org/Archives/Public/www-webont-wg/2003Dec/0100.html > > [3] http://lists.w3.org/Archives/Public/www-webont-wg/2003Dec/0035.html > [4] http://lists.w3.org/Archives/Public/www-webont-wg/2003Dec/0042.html > [5] http://lists.w3.org/Archives/Public/www-rdf-comments/2003OctDec/0233.html > [6] http://lists.w3.org/Archives/Public/www-webont-wg/2003Dec/0102.html > [7] http://lists.w3.org/Archives/Public/www-webont-wg/2003Dec/0106.html
Received on Thursday, 22 January 2004 15:42:59 UTC