Fixed skolem text with simple entailment (#157)

* Better text in Section 5.3 on propositions, facts, and asserted facts.

* Added rdfs:Proposition explanation in RDFS Section

* Added comment on rdf:reifies having no semantic condition in RDF

* accepted P-A improvement in text

Co-authored-by: Pierre-Antoine Champin <[email protected]>

* accepted P-A improvement in text

Co-authored-by: Pierre-Antoine Champin <[email protected]>

* accepted P-A improvement in text

Co-authored-by: Pierre-Antoine Champin <[email protected]>

* accepted P-A improvement in text

Co-authored-by: Pierre-Antoine Champin <[email protected]>

* accepted Niklas text improvement

Co-authored-by: Niklas Lindström <[email protected]>

* accepting Niklas amended text

Co-authored-by: Niklas Lindström <[email protected]>

* accepted Andy's suggestion

Co-authored-by: Andy Seaborne <[email protected]>

* Added a brief intro on rdf:reifies

* Block commit of all the suggestion until 10 September

* Applied @TallTed suggestion

Co-authored-by: Ted Thibodeau Jr <[email protected]>

* Fixed skolem text with simple entailment

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Co-authored-by: Pierre-Antoine Champin <[email protected]>
Co-authored-by: Niklas Lindström <[email protected]>
Co-authored-by: Andy Seaborne <[email protected]>
Co-authored-by: Ted Thibodeau Jr <[email protected]>

Author: 5 people

spec/index.html

@@ -780,7 +780,7 @@ <h2>Skolemization</h2>
     sk(G) <a>simply entails</a> H if and only if G <a>simply entails</a> H.</p>
 
   <p>The second property means that a graph is not logically <a>equivalent</a> to its skolemization.
-    Nevertheless, they are in a strong sense almost interchangeable, as shown the next two properties. The third property means that even when conclusions are drawn from the skolemized graph which do contain the new vocabulary, these will exactly mirror what could have been derived from the original graph with the original blank nodes in place. The replacement of blank nodes by IRIs does not effectively alter what can be validly derived from the graph, other than by giving new <a>name</a>s to what were formerly anonymous entities. The fourth property, which is a consequence of the third, clearly shows that in some sense  a skolemization of G can "stand in for" G as far as entailments are concerned. Using sk(G) instead of G will not affect any entailments which do not involve the new skolem vocabulary.  </p>
+    Nevertheless, they are in a strong sense almost interchangeable <a data-cite="RDF12-SEMANTICS#simple">RDF simple interpretations</a>, as shown the next two properties. The third property means that even when conclusions are drawn with <a data-cite="RDF12-SEMANTICS#simple">simple entailment</a> from the skolemized graph which do contain the new vocabulary, these will exactly mirror what could have been derived with <a data-cite="RDF12-SEMANTICS#simple">simple entailment</a> from the original graph with the original blank nodes in place. The replacement of blank nodes by IRIs does not effectively alter what can be validly derived with <a data-cite="RDF12-SEMANTICS#simple">simple entailment</a> from the graph, other than by giving new <a>name</a>s to what were formerly anonymous entities. The fourth property, which is a consequence of the third, clearly shows that in some sense  a skolemization of G can "stand in for" G as far as <a data-cite="RDF12-SEMANTICS#simple">simple entailments</a> are concerned. Using sk(G) instead of G will not affect any <a data-cite="RDF12-SEMANTICS#simple">simple entailments</a> which do not involve the new skolem vocabulary.  </p>
 
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