- From: Dan Brickley <danbri@danbri.org>
- Date: Thu, 19 Apr 2007 19:09:23 +0100
- To: Bijan Parsia <bparsia@cs.man.ac.uk>
- Cc: wangxiao@musc.edu, Alan Ruttenberg <alanruttenberg@gmail.com>, Jeremy Carroll <jjc@hpl.hp.com>, public-owl-dev@w3.org, Tim Berners-Lee <timbl@w3.org>, Alistair Miles <a.j.miles@rl.ac.uk>
Hi Bijan, Bijan Parsia wrote: > > Last for me in this thread for a while. > > On 19 Apr 2007, at 18:37, Xiaoshu Wang wrote: >> Or should I use rdfs:isDefinedBy, rdfs:seeAlso? > > No reasoner that I know of is, by default, sensitive to these. You could > preprocess and then feed into the reasoner, but that doesn't currently > have wide spread use. > >> If so, where is it specified? > > isDefinedBy and seeAlso are rather *un*defined. FOAF suggests using > seeAlso links, but I think the *content* of a foaf document is still > just the assertions in it, not the seeAlso's closure. Absolutely so. FOAF is just an RDF vocab. It has no magic voodoo to declare that "its" documents somehow include bits of other documents. This makes it safe to point a seeAlso at data from untrusted or unpredictable searches; they're just mentions of other documents that may be on roughly the same topic. This is one of the things I do like about RDF over XML: schema authors behaviour is limited such that you know in advance that someone else's schema can't do all kinds of crazy stuff. All they can do, more or less, is say a few quite limited things about classes and properties. The original use case for isDefinedBy was for the situation where you have a class or a property whose URI might be something like a UUID, ie. you can't syntactically figure out the namespace URI via regex. For rdfs:seeAlso there are a few notes in http://esw.w3.org/topic/UsingSeeAlso that might be of interest. cheers, Dan
Received on Thursday, 19 April 2007 18:09:48 UTC