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Re: The mentography of reification

From: Geoff Chappell <geoff@sover.net>
Date: Wed, 24 Oct 2001 16:46:39 -0400
Message-ID: <007401c15ccd$28d91150$0400a8c0@GSC866>
To: "Seth Russell" <seth@robustai.net>, "RDF-LOGIC" <www-rdf-logic@w3.org>
My understanding is that the triple can be thought of as defining a
particular arc in a graph. That nodes and arcs have identities (locations on
a page, position in memory, or whatever) and labels.  That with the
restriction that no two nodes can have the same label, we can uniquely
identify a node by its label. That with the restriction that duplicate
triples can not exist, we can uniquely identify an arc by the nodes it
connects (in order) and the label on the arc. (Nodes, I guess, are asserted
into existence by their use in describing an arc?)

Taking that view, I'd always envisioned that a nested or reified triple
would be shown on a graph as arcs originating or terminating on arcs (though
I don't know about the validity of that in graph-speak). And that the fabled
statement id is the identity of a particular arc. A quad in that view, I
guess, is really just a statement that there exists an arc with this label
and attached to nodes with these labels.

I guess, though, that the idea of drawing sets around nodes and arcs fits
better with a document-centric (triples in a context) view of the world. It
does seem somewhat funny, though, to be enclosing the nodes - it seems to
imply that their id's are locally scoped.

Geoff Chappell

----- Original Message -----
From: "Seth Russell" <seth@robustai.net>
To: "SEM-DEV" <sem-dev@yahoogroups.com>; "RDF-LOGIC" <www-rdf-logic@w3.org>
Cc: "Pat Hayes" <phayes@ai.uwf.edu>
Sent: Wednesday, October 24, 2001 2:27 PM
Subject: The mentography of reification


> It seems that the RDF WG is grappling with various syntactic
understandings
> of RDF reification.  But this phrase I have learned from wise men keeps
> rolling around my head:  "It's all about the graph, stupid.".     So I
> thought I would take a stab (not my first) at representing RDF reification
> within the graphical notation of mentography.    I would like to submit
the
> following mentograph for your comments:
>
> http://robustai.net/mentography/reificationContext.gif
>
> Notice that in mentography we use circles containing labeled directed arcs
> exactly like Venn diagrams represent members of a set.
>
> What is interesting is that converting from representing context as the
quad
> (stid, subject, predicate, object) to using the quad
> (context,subject,predicate, object) as is done in N3 does not in fact
change
> the shorthand notation in the graph:)    See a previous attempt using the
> former quad:
>
> http://robustai.net/mentography/MentographySemenglish.gif
>
> Seth Russell
Received on Wednesday, 24 October 2001 16:50:49 GMT

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