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Re: Linkbases, Topic Maps, and RDF Knowledge Bases -- help me
- From: "Thomas B. Passin" <email@example.com>
- To: xml-dev <firstname.lastname@example.org>
- Date: Sat, 07 Apr 2001 17:22:06 -0400
Uche Ogbuji said
> Here's the problem. I think that class is quite different than type, and
> that the subclass relationship is quite different from subtype.
> I was hoping to avoid placing my creds in jeopardy by offering up a
> definition of class and type, but I guess I can't avoid it.
> I think that a lot of my recent and growing skepticism of the power of OO
> to model the real world comes from the confusion between types and
> classes that is prevalent in languages such as C++ and Java.
> Another confounding factor is whether we use the terms type and class in a
person sense or a computer-software sense. In non-computer usage, a "class"
is usually much more like a "type" than it is in software usage. Now if we
are going to use our system (perhaps RDF) to do some first-order logic
tasks, we will end up using both terms in both worlds. How's that for
> I'm not saying that they're not useful. I'm just saying that RDF should
> be low-level or high-level, but not both at the same time. If it
> defines containers, it should probably define N-ary relationships, which
> are probably as common and useful in typical RDF use-case.
I'm totally with you here. I think that N-ary relationships are important
and need to be handled, and I'm not convinced that they can be properly
handled by multiple binary associations. Coming from a some modest
baclground with Conceptual Graphs, some of the things I see in both RDF and
Topic Maps just mystify me. Things that seemed like they were simple and
straightforward ended up obscured and complex, or at least unclearly
defined, and in the name of What??? No doubt there were ***Good
Reasons*** - there usually are, aren't there?