Re: Fwd: Re: TMRM: isa/sub - irreflexive relation vs. reflexive relation

On 09/10/11 07:43, Lars Marius Garshol wrote:
> * Alexander Johannesen
>>
>> Of course it's obvious what that /technically/ means. My question was
>> what does it mean to us, to humans, to we who make Topic Maps and deal
>> with the semantics, what does it mean to those of us who not only live
>> in the representational world but also in the real one. Ie, can you
>> come up with an example that makes sense from our world rather than
>> the world of set theory or OO?
>
> No.
>
> However, remember that classes don't actually exist in the real world.
> You're never going to see or touch a class. So if you want to leave
> the representational world behind then basically you've also left
> classes behind, and the whole issue becomes meaningless.

Hi Lars Marius,

The whole point of Topic Maps (explicit in the name) is to map a
territory. I'm not exactly sure what you're trying to say in positing
that anyone wants to leave the representational world behind. Does
this mean that one is giving up on representation, or that the
territory one is mapping is non-representational?

In the first case one is in the realm of the surreal; in the second
the realm of the abstract, such as logic or ontology itself.

I believe the first is out of scope for this discussion, and likely
Topic Maps as well (though experiments might prove interesting).

Of the second, if one is trying to make statements about say, ontology
(which seems to be the case here, as we're considering outlier cases
e.g. "class isa class"), then it's a simple matter of remembering that
the map and the territory one is mapping aren't at the same level (or
context). So "class isa class" is a non-sequitur in a context-free
logic. In a number of logics "class isa class" may be a requirement
in order to make the system work (showing how divorced such systems
are from reality, or how weak), but as Alexander is pleading for an
answer, the answer is that "x isa x" does not make any sense (is
meaningless) in the real world. But I suppose that's what you are
saying as well.

Murray

...........................................................................
Murray Altheim <murray11 at altheim dot com>                       = =  ===
http://www.altheim.com/murray/                                     ===  ===
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