Re: RDF* semantics

On Mon, 2019-09-02 at 00:30 -0400, Kingsley Idehen wrote:
> [...]
> Olaf,
> 
> Is the following an accurate working example ?

Yes (when considering RDF* as syntax sugar).

When considering RDF* as an abstract data model, the RDF* triple
(written in Turtle* syntax, prefix declarations omitted)

  :Alice :asserts << :Bob foaf:age"23"^^xsd:integer >> .

should be semantically equivalent to the following set of five RDF
triples (assuming we use RDF* in SA mode):

  :Alice  :asserts  [ a rdf:Statement;
                     rdf:subject :Bob ;
                     rdf:predicate foaf:age ;
                     rdf:object "23"^^xsd:integer
                    ] .

Best,
Olaf


> ## Turtle Start ##
> 
> @prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
> @prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
> @prefix xsd: <http://www.w3.org/2001/XMLSchema#> .
> @prefix foaf: <http://xmlns.com/foaf/0.1/> .
> @prefix : <#> .
> 
> <> a foaf:Document .
> <> foaf:name "Document about Alice"@en .
> <> foaf:primaryTopic :Alice .
> 
> :Alice  rdf:type  foaf:Person .
> :Alice  foaf:name  "Alice" .
> 
> :Bob  rdf:type  foaf:Person .
> :Bob  foaf:name  "Bob" .
> :Bob  foaf:age "23"^^xsd:integer .
> 
> # Context clarity regarding :asserts relation
> 
> :asserts a rdf:Property .
> :asserts rdfs:domain foaf:Person .
> :asserts rdfs:range rdf:Statement .
> 
> # :Alice :asserts << :Bob foaf:age"23"^^xsd:integer >> .
> # is suggested syntax sugar what follows
> 
> :Alice  :asserts  [ a rdf:Statement;
>                      rdf:subject :Bob ;
>                      rdf:predicate foaf:age ;
>                      rdf:object "23"^^xsd:integer
>                   
>                   ] .
> 
> ## Turtle End ##
> 
> Kingsley 
> 
> >
> >
> >> I am suggesting this in significant part because I like
> >> to think and speak of triples/quads as assertions, which
> >> obviously have provenance (e.g., the asserter, at a place,
> >> at a time, in a document), among other attributes.
> >>
> >> I dislike thinking or speaking of triples/quads as facts,
> >> because facts do not typically have provenance as such --
> >> they simply *are* -- and because triples/quads can be just
> >> as easily used to encode falsehoods and nonsensicals as
> >> truths (e.g.,
> >>
> >>    { PREFIX  ex:  <#>
> >>      ex:the_sea  ex:is    ex:boiling_hot .
> >>      ex:pigs     ex:have  ex:wings .
> >>    }
> >>
> >> ),
> >> and the simple (ahem) fact that such statements have been
> >> encoded as triples/quads should not be sufficient to
> >> indicate that they are (or ever have been, or ever will
> >> be) true -- nor even *asserted* to be true.
> >>
> >> (I might, for instance, encode a number of falsehoods as
> >> triples within a named graph, which is then used to test
> >> whether other named graphs should be considered more or
> >> less trustworthy, based on the number of such falsehoods
> >> contained in the graph under test.)
> >>
> >>
> >> (Who is this "Ted" guy?  I've been employed by OpenLink
> >> Software, working with Kingsley et al since late 2000, and
> >> involved in a number of W3 XGs, CGs, and WGs in that time.
> >> Recent highlights include late-term co-chairing of the
> >> SHACL WG, and active contributions to the Verifiable Claims
> >> WG and the Credentials CG.)
> >>
> >> Regards,
> >>
> >> Ted
> >
>

Received on Monday, 2 September 2019 07:20:36 UTC