- From: pat hayes <phayes@ai.uwf.edu>
- Date: Fri, 6 Sep 2002 00:25:09 -0700
- To: Jeremy Carroll <jjc@hplb.hpl.hp.com>
- Cc: www-webont-wg@w3.org
> >I don't see any a priori reason why set theoretic truths have any >greater need to be included in Owl than arithmetic truths. > Both set thery and arithmetic are really somebody else's concern. > > >Jeremy One of the things that is so misleading about the entire description-logic way of thinking is that it treats some *logical* truths as set-theoretical truths. Look, to infer John is a student and John is an employee . from John is a student. John is an employee . is a *logical* matter. It has to do with the meaning of 'and'. It has nothing to do with sets or classes or any of this paraphanalia. But in the warped world of description logics, to assert a simple conjunction requires us to invent a conjunctive class (an intersection) and say that John is in it. The reason for this intellectual warping goes back to an influential, but I think perverse, publication by Ron Brachman about 20 years ago, which invented the distinction between two 'kinds' of reasoning: that to do with meanings, which is supposed to be done in one place (the 'A-box') and the other to do with facts, supposed to be done elsewhere (the 'T-box'). The same kind of distinction is sometimes expressed by the distinction between 'data' (mere facts, assertions which are true) and 'meta-data' (schemas; things that 'define the meanings' of the terms used in the facts.) None of these distinctions make any logical sense or have even the slightest basis in semantics: they are pragmatic distinctions invented to facilitate effective use of database technology with simple reasoners. By using them as the basis for the *semantic* framework of the semantic web we are making the entire future of the Web hostage to the intellectual apparatus of a technology designed for the efficient use of regularized, commercial databases, not to the emergent world of a social semantic web. We should be focussing on the issues that will matter, not on how to transfer old technology into a world where it is probably going to be largely irrelevant. Pat -- --------------------------------------------------------------------- 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
Received on Friday, 6 September 2002 04:58:19 UTC