- From: Alex Kozlenkov <alex.kozlenkov@betfair.com>
- Date: Wed, 3 May 2006 16:18:59 +0100
- To: "Dave Reynolds" <der@hplb.hpl.hp.com>
- Cc: <public-rif-wg@w3.org>
Dave I am not sending a message against OWL or RDF. I am simply asking whether _querying_ RDF and OWL in rule antecedents is enough or not for RIF at this time. Reaction rules may involve a sequence of actions as opposed to one action. Semantics of these sequences of actions may be based on transaction logic or be even based on process algebras. OWL and RDF semantics are likely to be complementary to those. Alex -----Original Message----- From: Dave Reynolds [mailto:der@hplb.hpl.hp.com] Sent: 03 May 2006 15:14 To: Alex Kozlenkov Cc: public-rif-wg@w3.org Subject: Re: [RIF] Reaction to the proposal by Boley, Kifer et al Alex Kozlenkov wrote: > There are a few general concerns we have about the points raised by > Peter in that RDF/OWL should be first-class citizens in RIF. Firstly, > the production/reaction rules should play a good part of the standard. > As I understand it, it has been an industrial requirement all along, > certainly from our company. PR/RR have their own semantics that is not > directly compatible with, say, RDF deduction. In what way? Or for that matter what do you mean by "RDF deduction" in that context? A similar question was asked a few weeks ago in the form "does this mean that all RIF processors have to build in the RDF semantics" (where "this" = the "RIF must accept RDF data" design constraint). My personal response to this was "not necessarily", see: http://lists.w3.org/Archives/Public/public-rif-wg/2006Apr/0066.html But in any case, I don't see the fundamental incompatibility between specifically RDF and production rules. For example, the Jena software includes a simple RETE-style production rule language for processing RDF and it seems to do a useful job for quite a few users. Perhaps you could spell out what specific problems you see and we can look at ways of solving those. Support for RDF and OWL are clear parts of the RIF charter and have also been an "industrial requirement all along". At issue is the *way* in which we support them, not whether. > Secondly, tying RIF closely to OWL would effectively assume that > well-designed OWL ontologies become a prerequisite to do any meaningful > form of inference. I'm sorry but that is a non sequitur. Just because it would be *possible* for RIF rules to meaningfully refer to an OWL ontology and exploit some part of its semantics in no way implies that all RIF applications *have* to use OWL, let alone making its use a prerequisite for all "meaningful" inference. > The reality of large software projects is that it may > be prohibitively expensive to construct and maintain a consistent and > complete set of reference ontologies even for a subset of the main line > of business. This is irrelevant to the requirement that RIF be *able* to work with OWL. However, even in projects which do use OWL this is not a requirement. The semantic web does not call for a complete top down formal ontology of everything in your domain. One can perfectly well make use of ontologies which cover some small interesting fragment of your domain. The semi-structured nature of RDF is a key benefit in such situations, it allows you to make flexible trade-offs in the degree of axiomization of your domain. > What I am saying > is that rules may have to play a pragmatic role than other parts of the > Semantic Web technologies hence tying them closely with these parts may > hinder the success of the rules technologies per se. You seem to be setting up a false dichotomy between pragmatic and semantic web. We routinely use semantic web technologies in highly "pragmatic" ways in current business applications :-) > I was wondering if you think these two observations are making sense. No sorry, not to me. Dave ________________________________________________________________________ In order to protect our email recipients, Betfair use SkyScan from MessageLabs to scan all Incoming and Outgoing mail for viruses. ________________________________________________________________________
Received on Wednesday, 3 May 2006 15:19:22 UTC