Extending the baseline with "asserted" stuff - syntax & semantics

Following the long discussion on “asserted” stuff, some time ago I proposed to Thomas a way to extend the baseline capturing the gist of the discussion. Since I did not get any feedback on that, in the last Semantics TF meeting I made the proposal public.
This propoal should capture the gist of what has been discussed by Thomas, Souri, Gregory Williams, and others.

The proposal is at https://github.com/w3c/rdf-star-wg/wiki/Extending-the-baseline-with-%22asserted%22-stuff.

I paste it below for simplicity.

Extending the baseline with "asserted" stuff (DRAFT 2024.07.31)

<https://github.com/w3c/rdf-star-wg/wiki/Extending-the-baseline-with-%22asserted%22-stuff#extending-the-baseline-with-asserted-stuff-draft-20240731>

We extend the syntax and semantics of the baseline<https://github.com/w3c/rdf-star-wg/wiki/RDF-star-%22working-baseline%22> by adding a new property rdf:asserts, which has been called also rdf:states.


Along this line, somebody proposes to change the name of rdf:reifies to rdf:describes, but by now we assume not to change the name in the baseline; a discussion about names in this extension may be necessary.


We extend the well-formed syntax as follows:


tripleStructure  ::=  ... | ( reifier rdf:asserts tripleTerm )



and extend the interpretation of a triple if the predicate is rdf:asserts, in order to enforce the truth of the triple associated to the triple term as follows:


[I+A](t) = TRUE   iff   <[I+A](t.s), [I+A](t.o)> ∈ IEXT([I+A](t.p)) and
                        [I+A](t.o) = TRUE    if   t.p = rdf:asserts



OBSERVATIONS


:a rdf:asserts <<(:s :p :o)>> .
  entails
:s :p :o .

:a rdf:asserts <<(:s :p :o)>> .
  is equivalent to
:a rdf:asserts <<(:s :p :o)>> .
:s :p :o .



This extension may be more suitable to extend RDFS and not RDF, since reasoning is needed to complete the graph.


It has been suggested that the mapping between RDF-star and LPGs<https://github.com/w3c/rdf-star-wg/wiki/RDF-star-and-LPGs> should use rdf:asserts instead rdf:reifies.