Re: provenance of multiple triples all at once in RDF-star

Yes, I'm sorry, equating graph terms in Notation 3 with these is too
strong (especially since graph terms in N3, as currently defined, are
opaque). I meant it mainly as comparison.

(I also messed up my copy-pasting in my example, but I get that that
is not what you're disputing.)

What I'm looking for is if this set of unasserted, transparent triples:

    << :s1 :p1 :o1 >>, << :s1 :p1 :o2 >>

could be *syntactically* expressed as an unasserted, transparent set of triples:

    { :s1 :p1 :o1, :o2 }

Not unlike how these two forms of TriG sources:

    <g> { :s1 :p1 :o1 }
    <g> { :s1 :p1 :o2 }

and:

    <g> { :s1 :p1 :o1, :o2 }

both mean the same, and are equal to this in N-Quads:

    :s1 :p1 :o1 <g> .
    :s1 :p1 :o2 <g> .

Of course, if there is a fundamental difference, this won't work. Does
this difference state that it is not enough to consider something's
individual relations to otherthings as something's relation to the set
of those otherthings? Such as <a>'s set of friends <b> and <c>, by
saying:

    <a> foaf:knows <b>, <c> .

For the example at hand, if we change rdfx:occurrenceOf with
rdfx:states (as suggested in my previous mail). this :occurrence
resource:

    :occurrence rdfx:states << :s1 :p1 :o1 >>, << :s1 :p1 :o2 >> .

does appear (to me) to state two triples (which the above graph itself
does not assert); which implies, to me, that :occurrence constitutes
some kind of "occurrence" of the graph { :s1 :p1 :o1, :o2 }. That is
it relates to that graph, which is not in the graph we describe
(unless of course those triples are in that graph too).

I am thinking that for occurrences, this isn't the same problem as for
mathematical abstractions. I think I can see the mathematical
difference (<a> set of friends is a function of the set of <a>'s
friend relations), but if we really don't talk much about the sets
*themselves*, as mathematical abstractions, I wonder if we need this
difference.

Still, if we can clearly document that, that could also clarify the
difference between triple terms and graphs, which may perhaps be
enough (I have to test this more).

Best regards,
Niklas


On Sat, Dec 16, 2023 at 3:21 PM Peter F. Patel-Schneider
<pfpschneider@gmail.com> wrote:
>
> I dispute this equivalence.
>
> In :a :b << :s :p :o >> . :a :b << :s1 :p1 :o1 >> . there are two separate :b
> links from :a to two different triples.   In :a :b { :s :p :o . :s1 :p1 :o1 .
> } there is only one :b link from :a and it is to something that is not a triple.
>
> Perhaps some extension of some version of RDF might want to infer the second
> from the first but at the RDF graph level there is a fundamental difference.
>
> peter
>
>
>
> On 12/16/23 01:26, Niklas Lindström wrote:
> > Yes! And if we invert the relationship, as Andy has shown, to talk
> > about the occurrence, things really start to fall into place. We
> > talked about that at the end of the Semantics TF telecon (and looked
> > quickly at an example in IRC). That is, this:
> >
> >      :occurrence rdf:occurrenceOf << :s1 :p1 :o1 >> .
> >      :occurrence rdf:occurrenceOf << :s2 :p2 :o2 >> .
> >
> > ... is a named occurrence of a graph! That is, a graph term in Notation 3:
> >
> >      :occurrence rdf:occurrenceOf { :s1 :p1 :o1, :o2 } .
> >
> > can, conversely, be represented in RDF-star by the triples above.
> >

Received on Sunday, 17 December 2023 10:12:42 UTC