- From: Graham Klyne <Graham.Klyne@MIMEsweeper.com>
- Date: Fri, 11 Oct 2002 14:55:23 +0100
- To: pat hayes <phayes@ai.uwf.edu>
- Cc: w3c-rdfcore-wg@w3.org
At 12:38 PM 10/9/02 +0100, pat hayes wrote: >I hesitate to tread into this yet again lest I fall through the crust, but >heres an idea which might just keep everyone happy. It is a variant on the >old idea of semantically untidy literals, but it still supports the >critical tidy-style entailment. OK, I'll bite... You give us: Jenny ex:age '10' . ex:movie ex:title '10' . entails Jenny ex:age _:x . ex:movie ex:title _:x . But does: Jenny ex:age '10' . ex:age <datatyperange> xsd:integer . ex:movie ex:title '10' . ex:title <datatyperange> xsd:string . entail Jenny ex:age _:x . ex:movie ex:title _:x . ? If no, then this is non-monotonic. If yes, what is this value _:x that is in some sense both an integer and a string? #g -- >In our test-case style, here are the entailments you would get. > >Jenny ex:age '10' . >ex:movie ex:title '10' . > >entail > >Jenny ex:age _:x . >ex:movie ex:title _:x . > >BUT if you also say (ignore syntactic details) > >ex:age dtyperange xsd:integer . >ex:title dtyperange xsd:string . > >then that is OK, and now you can infer > >Jenny ex:age _:y . >_:y xsd:integer '10' . > >ex:movie ex:title _:z . >_:z xsd:string '10' . > >Obviously _:y isn't the same as _:z. The cost is, that _:x isn't the same >as either of them. In fact, _:x can't be a datatype value for *any* >datatype. Think of it as a kind of generic exemplar for the set of all the >possible datatype values, or something like that. Still, it *exists*. > >This could work with lexically tidy literals, but it would be classed as >semantically untidy, I guess. But it would be easy to tweak the MT to >allow this. > >Any takers? Questions? > >Pat > > >-- >--------------------------------------------------------------------- >IHMC (850)434 8903 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 ------------------- Graham Klyne <GK@NineByNine.org>
Received on Friday, 11 October 2002 09:30:31 UTC