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Elliotte Rusty Harold wrote:
> At 9:56 PM -0400 6/4/04, Thomas B. Passin wrote:
>> Right, an arbitrary piece of xml does not carry enough information to
>> let you automatically distinguish between elements that represent
>> things and those that represent properties. A person generally has
>> to work that out. But when you do have a properly striped format, it
>> can be easy to turn into rdf (it's usually just about there as is).
> Why is there a distinction between "things" and "properties"? Isn't a
> property a thing? Can't a property have properties of its own?
I'll jump in so I'm not letting my favourite permathread go without
A benefit of having descriptive statements in RDF is so that you can use
query and inference on them. You'll want to know that you can get
solutions, and get them in reasonable time. The logic (specifically
Description Logics) is reasonably well worked out around RDF/OWL, and
apparently the tractability goes out of the window as soon as you get
into fancy stuff with properties. A logician could probably be more
specific in their description of fancy stuff.
Essentially it's a trade-off between expressiveness and tractability.