July 29, 2003
Fragment IDs in Foaf?
Morten raises the point that my foaf group example doesn't clearly indicate that use of my foaf URL is intended to speak directly about me. It's a rather subtle sort of argument but a valid one. The issue here is that by using http://www.ideaspace.net/users/wkearney/foaf.xrdf alone, and with that file containing many different foaf:Person elements, I'm not really making a clear statement. Then perhaps I could make use of http://www.ideaspace.net/users/wkearney/foaf.xrdf#wkearney99 instead? I'd worry, however, that this isn't as helpful as it might seem. That and I'm not entirely sure how well RDF applications handle this sort of thing.
But yes, there does need to be a way to directly state "this URL is this entity's set of statements about itself". Note I say 'entity' as foaf can describe more than just people.
Well, the beauty of RDF is its ability to easily merge data from various sources, so a single source of statements wouldn't really be that useful. That said, the problem does exist, but for that there's foaf:topic (and foaf:page), and there's discussion about additional more focused properties (or classes).
In any case, FoaF has nicely dodged this issue by using the identifying properties declared as owl:InverseFunctionalProperty - that way, there's no need to try to identify a person by a single URI. If you change ISP, you don't lose your "identity", and won't have to tell people "I've moved"...
