- From: Graham Klyne <Graham.Klyne@MIMEsweeper.com>
- Date: Wed, 31 Jul 2002 09:40:26 +0100
- To: Dan Connolly <connolly@w3.org>, Pat Hayes <phayes@ai.uwf.edu>
- Cc: w3c-rdfcore-wg@w3.org, Eric Miller <em@w3.org>
At 06:53 PM 7/30/02 -0500, Dan Connolly wrote: >On Tue, 2002-07-30 at 18:31, pat hayes wrote: >[...] > > so even if C had intended to > > bad-mouth me, B's stupidity would have thwarted him. > > > > Hope this helps. > >Very, very much, it helps while away the time pleasantly ;-) > >And yes, it helps on rdfms-assertion, too, though >it may need to be edited just a touch before >release in a WD, no? Pat, as usual, your words illustrate the point very vividly. I expect I could rework it to a more professionally acceptable form, even if it would lose some of it's colour in the process (and probably also some of its illustrative power). Following input from Jos, I've reworked some of those sections to use some wording based on an earlier contribution of Pat's, whose overall effect is to reduce the volume of text without (I think) any loss of meaning (see excerpt below). So my questions are: (a) is the proposed rewording (below) any clearer? (b) should I work in the example -- I'm thinking an edited version might appear as a new section 2.3.5, illustrating what has gone before. I think final resolution of this could be left to a future WD round? #g -- Current new text for sections 2.3.3, 2.3.4: [[ 2.3.3 Interaction between social and formal meaning Using RDF, 'received meaning' can be characterized as the social meaning of any logical consequences. If you publish a graph G and G logically entails G', and we interpret G' using the same social conventions that everyone agrees could be reasonably used to interpret G, then you are asserting that content of G' as well. Human publishers of RDF content commit themselves to the mechanically-inferred social obligations. The machines doing the inferences aren't expected to know about all these social conventions and obligations. The social conventions used to interpret a graph may include assumed truths, for which no logical derivation is available, and socially accepted consequences whose rules of deduction are embedded in arbitrary decision- making processes. Semantic web vocabulary gains currency through use, so also do semantic web deductionshave force through social acceptance. Semantic web deduction operates in a combination of logical and social (non-logical) dimensions. To support logical entailments, formal RDF meaning is based on a model theory (see section 2.3.1). The notion of truth is crucial: a possible world may correspond to some RDF if and only if the RDF statement is true in that world. The RDF core language provides a way to make simple formal assertions, with no machinery for formalizing allowable inferences. Inferences are performed by processes, embedded in software implentations, whose validity is not formally demonstrable, and must be assumed or trusted to be socially acceptable. It is expected that semantic web languages layered on RDF will give formal expression to allowable inferences, thus to allow provable deductions by generic software modules to replace individual ad-hoc implemenations. 2.3.4 Implications of asserting RDF When an RDF graph is asserted in the web, its publisher is saying something about their view of the world. (The mechanism for deciding whether or not a graph is asserted is not defined here, but it is presumed that the publisher's intent will be clear in some way.) When a user invokes an application, there is also a social and technical context of invocation that determines some set of RDF assertions that will be assumed to be true: the application itself, and any RDF files that are passed to it. Garbage-in, garbage-out applies: if the initial assumed facts are wrong or meaningless, the results will have little value. No specfic mechanisms for deciding or evaluating the validity of any such assertions are defined here. Noting that there is no single human opinion about the truth of some statements, the graph may further contain commentary for human interpreters to indicate the realm of human interpretation that should be applied. This means a graph may contain "defining information" that is opaque to logical reasoners. This information may be used by human interpreters of RDF informaton, or programmers writing software to perform specialized forms of deduction in the Semantic Web. ]] ------------------- Graham Klyne <GK@NineByNine.org>
Received on Wednesday, 31 July 2002 05:28:13 UTC