- From: Tim Berners-Lee <timbl@w3.org>
- Date: Tue, 6 Mar 2001 22:44:43 -0500
- To: <jos.deroo.jd@belgium.agfa.com>, <connolly@w3.org>, <www-rdf-logic@w3.org>, "Sandro Hawke" <sandro@w3.org>
> > > [Dan Connolly writing:] [...] > > > If you make the domain > > > of :of and :and be :Sum (aka :Integer) and recall that = denotes > > > daml:equivalentTo, > > > you can write "the sum of 4 and 3 is 7" as > > > [ :of 4; :and 3 ] = 7. > > And without that qualification, this doesn't work. Let's rename and > avoid [] for clarity. You're saying: > > 7 sum_of_2_part_1 4. > 7 sum_of_2_part_2 3. No, that's not what [] mean - (you can't just remove them!) they mean (in this case) There exists x such that x sum_of_2_part_1 4. x sum_of_2_part_2 3. x num:equals 7 . Tim PS: I wouldn't use daml:equivalent because 7 and a thing whose LHS is 2 and RHS is 5 are different for the reasons you menation - you could deduce that 2+4 was 7. There exists x such that x sum_of_2_part_1 4. x sum_of_2_part_2 3. x daml:equiavlent 7 . There exists y such that y sum_of_2_part_1 2. y sum_of_2_part_2 5. x daml:equivalent 7 . But x sum_of_2_part_2 3. x daml:equiavlent 7 . imply 7 sum_of_2_part_2 3 and similarly 7 sum_of_2_part_2 4 and so on...
Received on Tuesday, 6 March 2001 22:45:01 UTC