# Statements about statements

Plain RDF says that Tim Berners-Lee worked at CERN. It has no comfortable way to say *when*
that was true, *who* claims it, or that it was true twice over different periods (the
statement itself is not something you can point at).

The 1.2 generation of the specifications fixes that. [RDF 1.2](rdf12.ipynb) adds triple
terms and reifiers, so a statement becomes a term that other statements can describe;
[SPARQL 1.2](sparql12.ipynb) adds the patterns to query them; and
[SHACL 1.2](shacl12.ipynb) adds the constraints to require and validate them.

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