- From: Bijan Parsia <bparsia@isr.umd.edu>
- Date: Fri, 9 Dec 2005 09:32:14 -0800
- To: Enrico Franconi <franconi@inf.unibz.it>
- Cc: Uli Sattler <Ulrike.Sattler@manchester.ac.uk>, public-rif-wg@w3.org
On Dec 9, 2005, at 2:24 AM, Enrico Franconi wrote: >>> On 8 Dec 2005, at 14:49, Enrico Franconi wrote: >>>> While I believe, like you, that tehre may be the necessity of >>>> different behaviours of reasoners, this can only be justified by >>>> the existence of different semantics for the same rule constructs. >>> >>> Do you mean that, for such a case, we should provide 2 different >>> syntactic constructs to make this difference explicit? For example >>> "implies1" for horn rules without contraposition and "implies2" for >>> horn rules with contraposition? >> >> Or you could have a flag for the whole document which one could >> override at one's own risk. > > Well, if it is "at one's own risk", then anything can be overridden :-) Well, there are risks that one might reasonably encourage and ones you'd like to strongly discourage. > Anyway, the option to override assumes that we have the possibility of > distinguishing the operators and their semantics upfront; we may then > decide to ignore such distinction at our own risk. Of course. My thought was more that if I have a collection of function free horn clauses, I might reasonably decide on some occasion to evaluate them under minimal model semantics and other times not. It's not a big deal to have a different operator (since I can always find and replace/transform). Having different operators locally spelt differently facilitates (a certain way of ) mixing rules in the same document which may or may not be a good idea. Cheers, Bijan.
Received on Friday, 9 December 2005 17:33:13 UTC