- From: Bernard Vatant <bernard@universimmedia.com>
- Date: Fri, 5 Jan 2001 15:17:34 +0100
- To: "Pierre-Antoine CHAMPIN" <champin@bat710.univ-lyon1.fr>, "Graham Klyne" <GK@Dial.pipex.com>
- Cc: "RDF-IG" <www-rdf-interest@w3.org>
Hello I've been following your debate from an "outsider" viewpoint, since I've been involved in Topic Maps rather than in RDF, but am very eager to see how we'll get to the announced convergence between RDF and XTM. Similar problems have been widely tackled in long debates in XTM community. A resulting syntactic consensus you can find at http://www.topicmaps.org/xtm/1.0/ and some archives of debate at http://egroups.com/group/xtm-wg To make it short, the TM terminology and "philosophy" are as follows : "Entity" is not used, and "reification" as been lately declared "outlaw". "Subject", which represents what a Topic is about, is maybe what is nearest to "Entity" as I understand it - or maybe "entity" is something between "subject" and "topic" - ... anyway ... subjects are split in "addressable subjects" and "non-adressable subjects", e.g. http://www.w3.org/TR/REC-rdf-syntax is an addressable subject, but "RDF Model and Syntax Specification" is a non-adressable subject. The first one being an addressable proxy for the second, it may be called Subject Indicator Reference, and is used to define the Subject Identity, the following syntax being used : <topic id="RDF-Model-and-Syntax-Specification"> <subjectIdentity> <subjectIndicatorRef xlink:href="http://www.w3.org/TR/REC-rdf-syntax"/> </subjectIdentity> </topic> Another addressable resource "representing" the same subject, e.g. whatever "elsewhere.org/RDF/Model_and_Syntax_Specification/description.htm", will be attached to the topic as an occurrence. A Topic Maps 0.02 in your terminologicus debate. BTW I'd like we have some open dedicated discussion space on the convergences/divergences of terms and concepts between RDF and XTM. Yours --------------------------------------- Bernard Vatant bernard@universimmedia.com www.universimmedia.com "Building Knowledge" --------------------------------------- ----- Message d'origine ----- De : Pierre-Antoine CHAMPIN <champin@bat710.univ-lyon1.fr> À : Graham Klyne <GK@Dial.pipex.com> Cc : RDF-IG <www-rdf-interest@w3.org> Envoyé : vendredi 5 janvier 2001 10:34 Objet : Re: RDF Terminologicus > Graham Klyne wrote: > > >I guess we should refer to [RFC 2396] where TBL defines a resource as > > >"a mapping to an entity or a set of entities". > > >Web resources' entities are pieces of data, and the same URI can map to > > >more than one piece of data, depending on the retrieval context. > > >RDF resources' entities can also be human beings, places, etc... > > >When a resources maps to an entity, > > >we will often say that the resource represents/models/stands for the entity. > > > > Ouch! I was using entity above in a non-RFC2396 sense. > > I think that the term "entity" in RDF2396 can be understood in its most general sense; > what is important to keep in mind is that resources are *not* entities, they map to them. > e.g. : the URI > mailto:champin@bat710.univ-lyon1.fr > identifies a resource which "maps to" / "stands for" entities like my mailbox or myself, > depending on the use you make of it. > This is how I undestand RDF2396; there is no restriction on the definition of entity here. > > > A simpler approach > > is to not try and define "stand for" and see if its use in the definition > > of 'reification' can "stand" unsupported > > On the contrary, I think it is an important definition : > the terms "represents", "models" or "stands for" are quite intuitive, > and hence we use them a lot, so they deserve a formal definition.
Received on Friday, 5 January 2001 09:19:56 UTC