diff --git a/spec/index.html b/spec/index.html index 0f44e08..11ff70c 100644 --- a/spec/index.html +++ b/spec/index.html @@ -504,6 +504,8 @@

Simple Interpretations

the referent of the subject and object of any true triple will be in IR; so any IRI which occurs in a graph both as a predicate and as a subject or object will denote something in the intersection of IP and IR.

+

We observe that no IRI, not even those in the rdf: namespace, + has any special semantic condition associated with it in a simple interpretation.

Semantic extensions may impose further constraints upon interpretation mappings by requiring some IRIs to denote in particular ways. @@ -722,19 +724,36 @@

Properties of simple entailment and satisfiability

We define the set of propositions in an interpretation as follows:

-

The set of propositions in an interpretation I is IPR(I) = { IT(x, y, z)|x is in IR, y is in IP, z is in IR }; we observe that a proposition is in the extension of rdfs:Proposition.

+

The set of propositions in an interpretation I is + IPR(I) = { IT(x, y, z) | x is in IR, + y is in IP, z is in IR }.

+ +

The denotation of a triple is a proposition, whether it is used as a triple + term or an asserted triple. Under RDFS + Interpretations (see below), a proposition is in the extension of the + class rdfs:Proposition.

We define the set of facts in an interpretation as follows:

-

The set F of facts in an interpretation I is F(I) = { IT(x, y, z)|<x, z> is in IEXT(y) }. The set of facts is the set of propositions which are true in the interpretation.

+

The set F of facts in an interpretation I is F(I) = { IT(x, y, z)|<x, z> is in IEXT(y) }.

+ +

A fact in an interpretation is a proposition that holds in it, corresponding to a triple which is true in that interpretation.

Given a blank node mapping, we define the set of facts asserted by a graph in an interpretation as follows:

-

Given a blank node mapping A, the set of all facts asserted by a graph G in an interpretation I is FEXT(G, I, A) = { IT( [I+A](s), I(p), [I+A](o) )|`s p o.` is in G }. We then observe that given a blank node mapping, the asserted facts of a graph with respect to an interpretation may not necessarily be among the facts of the interpretation.

+

Given a blank node mapping A, the set of all facts + asserted by a graph G in an interpretation I is FEXT(G, I, + A) = { IT( [I+A](s), I(p), [I+A](o) )| + `s p o.` is in G }.

-

We introduce a general definition of satisfiability of a graph in an interpretation as follows:

- -

An interpretation (simply) satisfies a graph if and only if there exists a blank node mapping such that the facts asserted by the graph in the interpretation are among the facts of the interpretation.

+

Given a blank node mapping and an interpretation, an asserted fact in a graph is the proposition corresponding to the denotation of a triple in the graph. These asserted facts may not necessarily be among the facts in the interpretation. + Intuitively, this would only be the case if the interpretation satisfies the graph. +

+ +

An interpretation I (simply) satisfies a graph G + if and only if there exists a blank node mapping A such that the facts + asserted by the graph in the interpretation FEXT(G,I,A) are a subset of + the facts of the interpretation F(I).

@@ -1243,9 +1262,18 @@

RDFS Interpretations

Extension in I) from IC to the set of subsets of IR.

A class may have an empty class extension. Two different classes can have the same class extension. The class extension of rdfs:Class contains the class rdfs:Class.

- -

An RDFS interpretation (recognizing D) is an RDF interpretation (recognizing D) I - which satisfies the semantic conditions in the following table, and all the triples in the subsequent table of RDFS axiomatic triples.

+ +

RDFS also introduces the class rdfs:Proposition, + whose extension is exactly the set of propositions as defined + in [[[#simple_entailment_properties]]]. + This class is also declared as `rdfs:range` of the `rdf:reifies` property. + In other words, the object of a reifying triple + always denotes a proposition. + +

An RDFS interpretation (recognizing D) is an + RDF interpretation (recognizing D) I which satisfies the + semantic conditions in the following table, and all the triples in the + subsequent table of RDFS axiomatic triples.

RDFS semantic conditions.