questionable statement in RDF semantics

The following statement in RDF Semantics, Section 2.1 is questionable.  (I
consider it to be incorrect, but perhaps there is another reading under
which it is not incorrect.)

	This means that there is no valid RDF inference process which can
	produce an RDF graph in which a single blank node occurs in triples
	originating from several different graphs. 

Consider Graph A

	ex:sa ex:pa ex:oa .

and Graph B

	ex:sa ex:pa ex:oa .

They entail

	ex:sa ex:pa _;a .

which contains a blank node that occurs in triples originating in both
Graph A and Graph B.

Peter F. Patel-Schneider
Bell Labs Research
Lucent Technologies

Received on Friday, 7 February 2003 08:36:28 UTC