Re: PMTM4 templates vs. TMCL (was: Re: [topicmaps-comment] RE: OASISvs W3C)

["Thomas B. Passin" <tpassin@home.com>]

[Steven R. Newcomb]

> True enlightenment is to fully grasp and enjoy both
> perspectives simultaneously.  *Both* perspectives are
> *essential*.

Absolutely.  To put it another way, topics are necessary to have something
to talk about, asssertions/associations are necessary to say anything about
them.  Just look at a Conceptual Graph (there I go again!) repesentation of
any sentence.  It's all associations and concepts (i.e., topics).

> The question, "Are topic maps about
> topics, or are they about assertions about topics?" is
> really a waste of time and energy.  Which brings me to
> my dark suspicion.
>
[...]

> All the same, it's very clear, at least to me, that we
> must support the assertion-centric perspective before
> we can support the topic-centric perspective.
>

We should concentrate on being able to say what we want about our topics.
That is the association-centric part.  At the same time, we have to
establish the universe of discourse.  That is the topic/taxonomy/ontology
part (notice that this is more than just topics per se).


> PMTM4 shows how Topic Maps eats its own dog food.  So
> far, I don't believe anything else that has been
> proposed truly does.  I'm open to the possibility that
> another model can also do this trick.  I'll certainly
> resist the adoption of any model that doesn't eat the
> dog food.  If nothing else, PMTM4 demonstrates that the
> dog food can be eaten.
>

Yes, but this does not rule out having a schema model, for example, that
extends what is already in topic maps.  The extensions become part of the
dog food.

In CGs, a conceptual graph can only have conceptual relations that have
their attached concepts.  But a conceptual relation is defined with slots or
roles that are to be filled with concepts when instantiated.  To properly
describe this, you need to introduce formal parameters (or lambda
expressions).  I'd suggest that we will ultimately need formal parameters in
topic maps, because otherwise we can't really define new associations
properly.  The reason is that we want the definitions or templates to be the
equivalent of classes rather than instantiated objects.  So we cannot refer
to any specific instance in a template, and thus we need formal parameters
to represent any and all instances.

With formal parameters you ***would*** be able to use a topic map to define
any new association or constraint you wanted to.  Without them, I'm not at
all sure you really can.

Cheers,

Tom P