- From: Drew McDermott <drew.mcdermott@yale.edu>
- Date: Wed, 1 May 2002 11:32:25 -0400 (EDT)
- To: www-rdf-logic@w3.org
[Pat Hayes] However, I still wonder if we need ['imports']. Consider the admittedly naive assumption that anyone who uses a vocabulary is committed to using it the same way. Then we don't need importing: just use the same names is all you have to do. Here are the problems with that idea (besides the ones I already described): 1. We have to distinguish names of individuals from names of properties. It's somewhat plausible that if I refer to a property then I should also accept the axioms about that property; if I don't, there's some question about whether I'm referring to the property at all. But URIs are used as proper names as well as names of predicates, and here things are much less clear. If I want to make a statement about the United Nations, and the URI www.un.world/#UN points to a web page containing all sorts of axioms (e.g., "Zionism is racism"), am I automatically committed to those axioms simply by referring to the UN? Presumably not. 2. "Anyone who uses a vocabulary is committed to using it the same way." But what do we mean by "a vocabulary"? If we have a well-defined notion of ontology, then a vocabulary is the set of terms introduced by the ontology. If we have a vaguer notion of everything reachable through an RDF graph, then it's not at all clear what commitment I am signing on to by pointing to a place in that graph. [Pat] OK, so it is going to break down at times; but I bet 'imports' is going to break down at times as well, because people will misunderstand the intended meanings in complex ontologies, and so on. The consequences are different, though. If a well-defined ontology breaks down, you fix it. If a flood of disconnected symbols breaks down, then what do you do? Seems to me that the only real purpose of having an 'imports' tag is to be able to NOT import some stuff you DONT want to agree to. So it might be more use, in fact, to have that as the primitive. It sounds to me like the user of a vocabulary has to draw the boundaries around it himself, watching out for leaks. (And what if a piece changes? There's no one version spec for the whole thing, so the vocabulary can acquire new boundaries like an ameba, and every user has to think about every new piece of membrane.) I'd much rather take what an ontology designer gives me, knowing that if a problem is encountered I know who to complain to. ... This suggests a vision of an SW which is in a constant process of self-repair. Pat, you offer the strangest mix of wild-eyed romanticism and hard-nosed logicism. In this message the eyes have it. I would vote with the nose. -- Drew
Received on Wednesday, 1 May 2002 11:32:29 UTC