[sc34wg3] 5.4.3 Topic Characteristics

Lars Marius Garshol sc34wg3@isotopicmaps.org
18 Nov 2003 03:35:37 +0100

* Patrick Durusau
| Yes, I think I see the difference you are trying to illustrate, but
| let me say it a little differently:
| [patrick : person]
| I read that as a statement about the topic "patrick", that is the
| symbol that represents the subject Patrick. The subject Patrick can
| only be represented in the topic map by use of a proxy, that is a
| topic.

Let me turn this on its head: who is an instance of "person"? You or
the topic? Clearly, it's the you, so you made a statement about the

Now, if we look at the subject identifier assignment, are we asserting
a relationship between the topic and the subject indicator, or one
between you and the subject indicator? Well, the subject indicator
itself asserts a relationship with you (it claims to describe you).
But the assignment is saying: "the topic is the thing described here".


    topic ------>  SI ------> subject

The TM statement is the first arrow, not the second, because the
second arrow is in the subject indictor, the resource, and that's
outside the topic map.

I agree this last bit is subtle. Maybe too subtle altogether. Graham
and I were actually wondering whether we shouldn't just ditch the term
"topic characteristics" completely. It's not clear that it's useful,
| In other words, all statements in a topic map are about topics, 

Clearly that's not true. Look at the Italian Opera topic map, for
example. Do you think Steve is saying that the topic representing
Puccini was born in Lucca? Of course he's not. He's saying Puccini was
born there.

| some of which are proxies for subjects in the Subject World

They all are. Not sure why you say this.

| (conceding your distinction for purposes of this argument only).

| Not meaning to get bogged down in the endless metaphysics that have
| bedeviled us in the past. I see a difference in how topic
| characteristics are handled in the TMDM from non-topic
| characteristics.  It may very well be the case that for clarity,
| efficency, processing requirements, etc., that the distinction is
| necessary but we need to have a good reason for the distinction.

The reason it's there is basically historical legacy. Graham and I are
not convinced that we need the term "topic characteristics", and if
that goes we could lose this whole discussion. With the term we have
to offer some rationale for what separates the topic characteristics
from the other properties.
Lars Marius Garshol, Ontopian         <URL: http://www.ontopia.net >
GSM: +47 98 21 55 50                  <URL: http://www.garshol.priv.no >