[topicmapmail] Re: Logicians do not rule the world (fortunately)

[Murray Altheim]

Quoting Steve Pepper <pepper at ontopia.net>:
>
> * Lars Marius Garshol
> |
> | > Note that symmetry does not need to be expressed, since symmetrical
> | > relations will always be represented in the following form:
> | >
> | >   borders-with(norway : neighbour, sweden : neighbour)
> | >
> | > Since both topics in the association play roles of the same
> | >  type, the association must be symmetric.
>
> * Murray Altheim
> |
> | You've with one statement already mixed an unnamed form of logic
> | with topography and/or political geography, also unnamed. The
> | danger in these kinds of statements is [etc...]
>
> This response seemed a little aggressive.
>
> Why do you assume some "unnamed form of logic"? Why do logicians
> think they have a monopoly on knowledge? What's wrong with common
> sense and everyday experience, which indexers and librarians have
> been using for centuries?

Steve,

I'm not a logician and I don't play one on TV (though I'm not
entirely sure of that since I don't watch TV), and there's
nothing to stop people from making statements using tools that
permit them to make statements, and Topic Maps are an excellent
way to make them.

What spurred my "aggressive" response was Lars Marius' response
about symmetry:

> | > Since both topics in the association play roles of the same
> | >  type, the association must be symmetric.

This statement can only be valid if there is a grounding in some
form of logic that would make it true. Either the symmetry of a
given statement must be made explicit (and the software tools
that operate on that symmetry must be trained to read the explicit
statement of symmetry and operate upon it accordingly), or the
entire enterprise must be grounded in a logic so that the relation
inherits the symmetric property.

Absent that, what I wrote is a simple statement of fact.

> It happens that Norway *does* border with Sweden and that this
> implies the unavoidable (symmetric) fact that Sweden borders with
> Norway. Why should we not be able to express that in Topic Maps
> without digging ourselves into a bottomless pit of logic?

Well, you can tell me that, and you can express that (i.e., write
it down) in a Topic Map, but stating it in a Topic Map in such a
way that can be reasoned upon by machines is an entirely different
matter. If you want an even rudimentary reasoning engine to be
able to connect the idea that

   if    Norway borders-with Sweden
   then  Sweden borders-with Norway

then the symmetry of the 'borders-with' relation must be stated
and the engine programmed to make that inference. I don't think
that this remotely digs anyone into a bottomless pit of logic.
I've written a rudimentary reasoning engine in Ceryle that makes
this simple inference, and it didn't take much coding.

I think it's a common mistake in every AI/KR community to state
properties of software that it doesn't innately possess, such as
use of the word "understand" or "know" or "mean" (I fall into
this verbal trap all the time, just from force of habit). The
idea that a Topic Map engine, absent the explicit statement of a
relation's symmetry, would somehow be able to deal with the
relation as if it were symmetric was what I was commenting on,
that's all. It's a variant form of anthropomorphization that we
should all be cautious of, lest we suddenly find ourselves the
authors of Scientific American nonsense about the "Semantic Web"
and how it "knows what we mean."

There is no meaning on the Web, nor in computers, nor is there
in books. I am always surprised to find how many supposedly
intelligent people don't understand this (i.e., don't know how
to interpret this statement).

Murray

...........................................................................
Murray Altheim <murray06 at altheim.com>                              ===  = =
http://www.altheim.com/murray/                                     = =  ===
SGML Grease Monkey, Banjo Player, Wantanabe Zen Monk               = =  = =

      In the evening
      The rice leaves in the garden
      Rustle in the autumn wind
      That blows through my reed hut.  -- Minamoto no Tsunenobu