[sc34wg3] What do we mean by reification?

[Lars Marius Garshol]

* Patrick Durusau
|
| OK, so we are quibbling about the word, reification vs.
| representation, for the topic / subject relationship? 

No, we are having a technical discussion about it.

| Speaking solely for myself, I have no objection to "representation"
| but I would use in all cases. If it is representation in one, then
| it seems to me it is representation in the other. (or the converse
| as well, reification in one is reification in the other, but as you
| point out, correctly in my opinion, it requires more explaination
| and hence "representation" should be preferred.)

In the RM this works, but in the SAM it does not. SAM needs a term for
the trick used to make topics represent base names/occurrences/assocs,
but the RM has no use for it.

| Actually I checked (assuming my copy of Acrobat is working properly) and
| reification does not appear in ISO 13250:2000.

See the note on the definition of "subject", section 3.18, page 4 (or
12 in Acrobat).

| So at least XTM 1.0 was consistent in using reification for both
| subjects (outside the topic map) and subjects (constructs within the
| topic map).

That's the problem. You need a term for the second case, but XTM
doesn't have one, having already spent the generally accepted term for
this on the first case.

| So, if we agree that the term "representation" is better for
| describing the topic / subject relationship in terms of clarity (I
| assume to people who are not part of the topic map community) what
| is being gained for implementers by using a special term,
| reification, consistently with the AI folks? Not that I particularly
| mind being consistent with the AI crowd but are we gaining anything
| by that consistency?

Why are you talking about implementors?

What we gain is having a term for the trick used to make topics
represent topic characteristics. I think a term for that is necessary,
but if people disagree we should discuss that.

| I think what I am missing is what makes this a "special case" of
| topic-represents-subject senario. At least in terms of why I should
| say reification versus representation.  Noting that if a subject
| identifier property of a topic equals the source locator item of an
| information item, then that topic reifies (in the current SAM sense)
| the information item. Admittedly mechanics are different from a
| topic that "represents" (in the SAM sense) a subject not in the
| topic map, but does the difference in mechanics merit a separate
| term for the relationship between topic / subject?

I think it does. Imagine trying to rewrite the SAM without this, and
trying to teach people XTM without being able to use this (or some
other, more appropriate) term for this concept.

BTW: Patrick, this email was 10832 lines, and the first part was plain
     text intermixed with HTML. It would be nice if you could go back
     to your usual posting style, because this was hard to read.

-- 
Lars Marius Garshol, Ontopian         <URL: http://www.ontopia.net >
GSM: +47 98 21 55 50                  <URL: http://www.garshol.priv.no >