[sc34wg3] SAM-issue term-scope-def

[Bernard Vatant]

> * Bernard Vatant
> |
> | I think all the debate is useless until we formally clear out the
> | meaning of several things:
> |
> | 1. What does "A is valid" mean?
> | 2. What does "S applies" mean?
> | 3. What is the logical status of "when"?

*Lars marius Garshol
> I think anything we say about 1 is going to be only so hot air in any
> non-mathemathical specification (and that's what this is). For all
> practical purposes it means "A is seen as true".

"seen"? by which users or process? It figures that scope assignment is also a statement
made by TM author, be it human or not (TM might be automatically built) so the full
sentence is:

"This TM states that: if this scope applies, then A is valid"

> 2 and 3 are very interesting, however. What they imply to me is that
> we need to define the notion of a context in which topic
> characteristic assignments are evaluated. They are either considered
> valid (if the scope matches) or invalid (if the scope does not match).

I understand what you say here as:
"A is valid *if and only if* scope applies" ...

That does not seem consistent with what you say elsewhere; I understood you supported:

"If scope applies, then A is valid"

> It's not that I disagree with your maths, Bernard, or that I don't
> want to use maths, but I think we need to either have a spec
> completely grounded in maths or completely divorced from it.

I don't figure how a specification pretending to define in a non-ambiguous way fundamental
objects, relationships between these objects, and rules about those relationships (is not
that what SAM is about?) could be completely "divorced from maths" (be they mine or others
BTW) or at least from common logic. What I am about is not here a formal mathematical
model, but checking elementary logic, e.g. if scope declaration supports a necessary
condition, or a sufficient condition, or both ...

> That's why I like this approach: I think it would allow us to clear this up
> in the natural language specification (SAM) and give a future
> mathematical specification something more precise to start from.
>
> Does that make sense to you, Bernard?

Well. I must confess I've never understood the whole process. We've started with syntax
with no model, now try to figure an application model in natural language, and then maybe
we'll try to have a mathematical or formal model ... but what if both syntax and "natural
language specification divorced from maths" contain such hidden inconsistencies that
nobody will never be able to build a consistent model of them? So even if SAM is not
expressed in maths language, which I fully agree with, it has to be checked for
consistency of its implicit underlying model rules.

Bernard