- From: pat hayes <phayes@ai.uwf.edu>
- Date: Sun, 26 Jan 2003 11:21:55 -0700
- To: "Peter F. Patel-Schneider" <pfps@research.bell-labs.com>
- Cc: www-rdf-comments@w3.org, w3c-rdfcore-wg@w3.org
>The closure rules for RDFS are incomplete. For example, > ex:foo ex:prop "a" . >RDFS-entails > ex:foo ex:prop _:x . > _:x rdf:type rdfs:Resource . >However, this does not come out of the RDFS closure rules. >This means that the RDFS entailment lemma is false. That is true, and I had indeed not previously noticed this case, which requires the notion of closure to be re-worded slightly. The inference can be obtained as follows: ex:foo ex:prop "a" . |= ex:foo ex:prop _:x . is sanctioned by the general RDF entailment conditions, and the other triple is then inferred by the rule rdfs4b. However, this means that the closure rules need to be applied *after* some RDF inference is performed. The definition of closure will be re-worded so as to first add all existential conclusions on triples involving literals, then apply the closure rules. This will handle this exceptional case. Pat -- --------------------------------------------------------------------- IHMC (850)434 8903 or (650)494 3973 home 40 South Alcaniz St. (850)202 4416 office Pensacola (850)202 4440 fax FL 32501 (850)291 0667 cell phayes@ai.uwf.edu http://www.coginst.uwf.edu/~phayes s.pam@ai.uwf.edu for spam
Received on Sunday, 26 January 2003 13:35:58 UTC