- From: Jim Hendler <hendler@cs.umd.edu>
- Date: Thu, 9 Oct 2003 22:56:14 -0400
- To: Sandro Hawke <sandro@w3.org>, pat hayes <phayes@ihmc.us>
- Cc: public-sw-meaning@w3.org
At 8:47 PM -0400 10/9/03, Sandro Hawke wrote: >> 1. If you derive a conclusion from a contradiction, then nobody is >> responsible for it but you: a derivation from a contradiction adds no >> weight to the conclusion at all, so if you publish it then that is >> just like publishing a brand-new assertion; you, the publisher, can't >> appeal to any other authority. >... >> Im sure there are others, but the first one is enough to handle your >> case, since if I publish a contradiction, then its not going to be >> any SW-style use to anyone else: they can't use it to do anything >> that they couldn't do on their own. > >While I agree with that, it doesn't help with my original concern, >which is how the use of a particular URI in an RDF graph affects how a >receiver of that graph might behave. If imagine you say to me (in the >document "pat"): > > pat:Donny a bio:Dingo. > pat:Donny a bio:Cat. > >I might well follow the bio link, and while I'll be nice and not hold >you to everything bio says, ... what should I make of the fact that >you've said Donny is an instance of two disjoint classes? Hrm. >Neither "pat" nor "bio" is inconsistent, but the combined set is >(assuming OWL semantics and that bio really used OWL). > >It seems to me that as a reader I'm not going to be too happy with >this graph you sent me. What have I really learned from you about >pat:Donny? What can I do with what you said? Not a lot, I think. >Ewwww. > >So working back, I end up saying you SHOULD NOT say things like that, >and MUST NOT do so knowingly. Sandro - supposing I wish to send you a graph that points out that NOW believes life says at birth but that the Nat'l Right to Life group says life begins at conception -- nrl:life :begins med:conception. now:life :begins med:birth. med:conception owl:disjoint med:birth. would you say I MUST NOT send you such a document? I'm confused -- Professor James Hendler hendler@cs.umd.edu Director, Semantic Web and Agent Technologies 301-405-2696 Maryland Information and Network Dynamics Lab. 301-405-6707 (Fax) Univ of Maryland, College Park, MD 20742 *** 240-277-3388 (Cell) http://www.cs.umd.edu/users/hendler *** NOTE CHANGED CELL NUMBER ***
Received on Thursday, 9 October 2003 22:57:44 UTC