should Concepts include information about REQUIRED datatypes

[pfps]

Semantics states that support of several datatypes is REQUIRED for RDF entailment but Concepts does not have any analogue of this requirement. I think that Concepts should discuss what is needed for RDF entailment.

[afs]

This seems to be covered by section 1.8? It refers to RDF Semantics for entailment regimes.

Then in "RDF Semantics", RDF entailment is built on Simple entailment

Every graph is simply satisfiable.

and that's before datatypes

RDF Semantics section "5 Simple Interpretations" change note:

The full semantics for typed literals is given in the next section.

(The "next section" seems to mean section 7, not 5.1 or 6)

RDF Concepts needs to explain what a datatype is, and about lexical form and values, which it does. Requirements for entailment should be with the entailment content, which is in RDF Semantics.

[pfps]

But then why is there a RECOMMENDED in Concepts at all? It appears that something should be done.

[afs]

Link to the text please.

[pfps]

First paragraph of https://www.w3.org/TR/rdf12-concepts/#xsd-datatypes

[afs]

That is before "recognized datatype" is introduced.

RECOMMENDED == SHOULD.

It is giving good practice - use certain XSD datatypes, which are RDF-compatible, and not different vocabularies for numbers, dates etc for interoperability reasons.

[afs]

RDF-Semantics does not reference RDF-Concepts for "recognized datatypes".

It has its own definition dfn-recognized.

[afs]

See also #60.