From: Dan Connolly (connolly@w3.org)
Date: 10/16/00
pat hayes wrote: > [...] > >In what way is > > The class C is the disjoint union of the classes > > in the list L. > >not an assertion? > > > That is an assertion, but according to your specs "the disjoint union > of the classes in the list L" has to be an assertion as well (since > it can be false). Which part of the spec suggests that? <Class ID="C"> <disjointUnionOf resource="#L"/> </Class> is an assertion; in English, see above. In KIF, it would be (disjoinUnionOf C L) but *not* (= C (disjointUnionOf L)) There are no operators, expressions, or anything like that, anywhere in RDF. There just aren't. There are terms (URIs and anonymous terms) and sentences (aka statements, aka assertions, aka triples, aka arcs) but nothing in between. > What I meant was that the value of disjoint-union > (or union or intersection etc) is normally taken to be a set, not a > truthvalue. If the classes in L are pairwise disjoint then > disjointUnion L is a set, but if they aren't it is false. There's no "disjointUnion L" construct separate from "C is the disjoinUnion of L". > (Now it is > true that "The class C is false" is probably false as well, but that > seems like a peculiar way to be false, and not what one would > normally mean by saying that your assertion about C and L was false.) > > Pat Hayes > > --------------------------------------------------------------------- > IHMC (850)434 8903 home > 40 South Alcaniz St. (850)202 4416 office > Pensacola, FL 32501 (850)202 4440 fax > phayes@ai.uwf.edu > http://www.coginst.uwf.edu/~phayes -- bind default <http://www.w3.org/People/Connolly/kb> <mailto:connolly@w3.org> is mailbox of [a Person; called "Dan Connolly"; affiliation [ a Consortium; called "W3C"; homePage <http://www.w3.org> ]; homePage <http://www.w3.org/People/Connolly/>; ]
This archive was generated by hypermail 2.1.4 : 03/26/02 EST