- From: Peter F. Patel-Schneider <pfps@research.bell-labs.com>
- Date: Tue, 23 Apr 2002 05:51:21 -0400
- To: jjc@hplb.hpl.hp.com
- Cc: connolly@w3.org, jonathan@openhealth.org, www-webont-wg@w3.org
From: "Jeremy Carroll" <jjc@hplb.hpl.hp.com> Subject: RE: SEM: circular primitive Date: Tue, 23 Apr 2002 10:20:10 +0100 [...] > Showing that I am still playing the game according to my preferred > rules of discussing concrete cases in sufficient, but hopefully > not exhaustive detail, let us consider Peter's child case. > > (In this case I fear it is exhausting but not exhaustive!) > > > R: > > KB1: > > John rdf:type Person . > > Bill rdf:type Person . > > John child Bill . > > entailing KB2: > > John rdf:type _:1 . > > _:1 rdf:type daml:Restriction . > > _:1 rdf:onProperty child . > > _:1 rdf:hasClass :_1 . > I personally think this, as stated, is false. But like Jonathan > I think it points to an important use case, for which I will give > my treatment. > I think R is false because: > If R is true then the premises also entail that KB3: > Bill rdf:type _:1 . Please explain. It is true that KB1 entails KB3, of course, because, there is a type for Bill, namely Person. However, how can KB1 entail KB2 plus KB3 (taken as a single graph)? Bill does not have a child, so he does not satisfy the conditions on _:1 in KB2. > and hence > > Bill child _:x . > _:x rdf:type _:1 . > > and I do not think that the premises should license the first triple > of such a conclusion. peter
Received on Tuesday, 23 April 2002 05:52:49 UTC