- From: Brian McBride <bwm@hplb.hpl.hp.com>
- Date: Wed, 24 Oct 2001 17:47:08 +0100
- To: Pat Hayes <phayes@ai.uwf.edu>
- CC: w3c-rdfcore-wg@w3.org
Pat Hayes wrote: >> Just checking we are clear what is being renamed. > > > Well, I thought I was clear, but now I am completely confused. > >> M&S uses the term predicate for a component of a statement. > > > That means a triple, right? Or a [node/edge/node] combination in an RDF > graph. Or does 'statement' mean something else? Right now, as I > understand it, there are triples in Ntriples, pieces of graph in the > graph syntax, and more complicated pieces of syntax in RDF/XML. Which of > these is called a statement? You have put your finger on a key question, that I think we need to get clear if we are to reconcile the language of the old M&S with the new model theory. We are dealing here with two formal models. M&S has a formal model, and we have the new model theory. I think that M&S has the concept of statement and the new model theory does not. My *personal* reading of M&S is that statement and triple meant two different things. o a statement is an abstraction; its a tuple with three components, subject, ... o a triple is a concrete representation of a statement, e.g. state in a computer memory, markings on paper etc. [I'm not defending this model; I'm just trying to express it. It may well be full of contradictions] How do these concepts relate to the new model theory. Well, a triple in n-triples is pretty clearly still a triple. What is an arc in a graph? Not a statement, I think. If I write: <:sky> <:is> <:blue> . <:sky> <:is> <:blue> . I clearly have two triples. I would also have two arcs in one of your graphs (until it got tidied). But to M&S, (as I interpret it, others would disagree) there is only one statement, because both triples denote the same statement. I find no concept similar to statement in the new model theory. Brian
Received on Wednesday, 24 October 2001 12:51:43 UTC