Re: &

["Sean B. Palmer" <sean@mysterylights.com>]

> Maybe what will prove as an essential solution for HumanML
> will be the definition of non-hierarchical relationship types.
> Much like that "aaron:kindaLike" (Aaron Swartz?).

Yep, that's Aaron's term.

A hierarchy stops becoming a hierarchy and becomes a Web when two nodes can
refer to each other, rather than being chained. So hierarchial structures
on a Web are fine, because they're not really hierarchial structres; or
rather, they're not limited to being hierarchial structures. It's a similar
thing with RDF. At the moment, you can't introduce cyclic
properties/classes (RDF Schema won't allow it), but once those are allowed
(it's on the RDFS issues list), it'll allow RDFS to imply equivalences in a
way that will baffle some non-logicians. Asserting that:-

   :x rdfs:subPropertyOf :y .
   :y rdfs:subPropertyOf :z .
   :z rdfs:subPropertyOf :x .

it may be quite interesting to watch people who are so used to hierarchies
deal with something like that. Ooh, I just came up with a good idea... if
we can have pairwise disjoint classes, why not have pairwise equivalent
resources?

   (:x :y :z) a :Equivalent .

Cool. @@ suggest that to www-rdf-logic, if someon hasn't already done so.

Anyway, what was I talking about? Oh yes, it's quite difficult to define
what a "non-hierarchial relationship" is, because all triples are miniature
hierarchies. When we link them together, they form a Web, which transcends
the triples, much like the triples transcend the nodes.

I'm not too keen on "kindaLike" because all it does is state that there is
some level of equivalence between a subject and an object, but it doesn't
state the level of that equivalence. That might be useful to a human (which
is why I used it in the prose), but it's not going to be useful to a
machine, which is what the goal of the Semantic Web is. To get machines to
do all of the dirty work.

So weak ontologies are probably a bad thing, but Webs of course triumph
over hierarchies. Hierarchies are terrible, terrible things :-) The ability
to trancend the object oriented model is a side-effect of being able to say
anything about anything, and is a good thing.

--
Kindest Regards,
Sean B. Palmer
@prefix : <http://webns.net/roughterms/> .
:Sean :hasHomepage <http://purl.org/net/sbp/> .