On 30 Mar 2009, at 16:49, Mark wrote:
On Mon, 30 Mar 2009 04:35:08 -0700, Bijan Parsia
<bpar...@cs.manchester.ac.uk> wrote:
that many ontologies (including the OBO ontologies and parts of the
Neurocommons Knowledge Base / Banff HCLS demo) encode a lot of
useful
information just by using classes and property restrictions,
without
instances.
It's a bit of a stretch to suggest that the OBO ontologies define
property restrictions... I certainly wish they would! :-)
"Instantiating classes" suggests something akin to what one does
in an
object oriented programming language. I.e., it suggests that
individuals are "created" from templates (aka classes). While OWL
Classes are used this way in KA systems, it requires careful thought
(and the intervention, typically of a "sanctioning" mechanism which
indicates which parts of the description are salient for the KA).
I actually worry about describing OWL/Ontologies this way - I think
it creates a mindset that is artificially limiting.
We agree. The problem is people rely *too much* on the analogy
instead of thinking about the points of disanalogy.
[snip]
To me, OWL gives us a framework to *interpret*
I say "describe" but we seem close.
the world, not to *define* the world. The fact that we can
purposefully create individuals that fit a particular model is, to
my mind, not the point! I try to get my students to think about
OWL as a "lens" rather than a "model" - it gives us a way to impart
meaning onto existing data, rather than create data that has a
particular meaning.
It can be used for the latter as well, of course.
The CardioSHARE project (http://sadiframework.org) is my attempt to
create a Semantic Web Services framework that "instantiates" this
view of the world... in SADI/CardioSHARE, ontologies are used for
*discovery*, not for a priori modelling.
I don't know if this is a *pragmatic* way to look at the Semantic
Web, but I've always been an idealist LOL! Wish me luck ;-)
Seems pragmatic to me.
Cheers,
Bijan.
