Re: Using rdf reification to nest statements in N3 like contexts

From: "Graham Klyne" <>
To: "Seth Russell" <>
Cc: "RDFIG" <>
Sent: Friday, March 15, 2002 2:23 PM
Subject: Re: Using rdf reification to nest statements in N3 like contexts

> At 12:28 PM 3/15/02 -0800, Seth Russell wrote:
> >From: "Graham Klyne" <>
> >
> > > Example:
> > >    A says { B says {C says D} . B a liar } .
> > > If I decide that what A says is true, I may enter the context of
> > > what A says and assert:
> > >    B says {C says D} . B a liar .
> > > If we have a syntactic construct for containment, as N3, then the
> > > of {...} can be treated opaquely as you suggest.  But when all this is
> > > encoded into a flat space of triples, some other mechanism is needed.
> >am
> > > proposing (multiple levels of) encoding as reification-quads.
> >
> >Well I think that coding a triple as the RDF reification quad makes it
> >default to being opaque (not necessarialy true) in every context ... in
> >other words a reified statement is simply not asserted in any context.
> Yes.
> >   If we want the statement to be true in some context we will need to
> > invent a
> >property that asserts in that context.
> I was presuming a very general technique:  one "enters" a context by
> performing one level of "unreification" -- create a new graph with each
> rdf:Statement resource in the context generating a statement (triple)
> containing the corresponding subject, object and property.  Using my
> scheme, inner nested contexts still appear as reification quads.  The top
> level statements of the context entered come out as (non-reified)
> statements, hence asserted.

Well I don't see how this works in any practical manner because  you could
only access a particular context via the expression tree in which it was
entered.  How could you say arbritrary things about arbritray context nodes

... anyway did I get the mentograph of your proposal right?  The ded arc
from C to the inner nested context labeled with the Bnode _:4 would, imho,
not show up correctly.

Seth Russell

Received on Saturday, 16 March 2002 11:10:54 UTC