Keith Devens .com

Have you ever looekd at Prolog? I still don't think I've completely grokked RDF but studying Prolog at University helped me make quite a few connections. Prolog is a "logic" programming language based around a list of facts relating things together, which seem to have a direct corollary in RDF triples. For example, in Prolog you can say "Joe is Jack's parent, Joe is male, a father is a parent who is male, tell me who Jack's father is".

Yeah, I've never actually used Prolog but I understand exactly what you're talking about. I'm familiar enough with Prolog to understand that application of it -- I'm just not sure how they made that into a full fledged programming language.

My understanding of RDF seems similar to yours, that an RDF triple is essentially a combination of SUBJECT, OBJECT, and RELATION (or predicate). So JOE (is a parent of) JACK is an RDF triple.

My problem with it is basically that while its simple, it's one of those things they try to generalize to the point of absurdity... or at least uselessness. And even though it seems like a fundamentally simple idea, somehow they've made it seem really complicated so that smart guys like us don't even understand it. I love Joel Spolsky's quote:

And if you go too far up, abstraction-wise, you run out of oxygen. Sometimes smart thinkers just don't know when to stop, and they create these absurd, all-encompassing, high-level pictures of the universe that are all good and fine, but don't actually mean anything at all.

So, RDF seems totally useless to me since anything that needs to model relations somehow can just do it without needing the baggage of RDF, and most things really don't need it (think RSS 1.0). Plus, it doesn't seem there's anything you can do with RDF by itself (in other words, it doesn't stand on its own), but when you add it to anything else it seems like all you really add is useless complexity.

"But that's just my opinion, I could be wrong." -- Dennis Miller

Haha, oops. I'm going to leave the name like that just for fun (don't worry about it, it shouldn't mean anything to you ).

RDF in 5 words:

moving ... data ... between ... sites ... - bitch.

it's funny, laugh

Haha, no.

:-P

Actually, RDF doesn't even do that, since RDF isn't even anything concrete on its own. You can't parse "RDF", because RDF doesn't have a syntax. XML/RDF is one possible syntax to represent RDF.

Indeed, RDF doesn't do anything on its own. And if you add it to something else it also doesn't seem to do anything useful. For instance, if all you want is content syndication, RSS would be suitable without the RDF.

RDF only makes sense if you think of something much more than a single RSS file. For example, by concatenating every RDF file in the world together. You can't do that with arbitrary XML -- you just get a jumbled mess.

I'm not expecting you or anyone else to understand why RDF is useful. Some people just won't. That's fine. I think for most people, one day a light goes on in their heads, and then they just 'get it'.