conclusion relation

Wed Aug 27 01:40:52 UTC 2008

Hello Manfred, and all,

Thanks for your thought-provoking comments.

I don't have time to respond to everything you say -- there's much I 
don't understand -- but I do have a few small questions.

At 8:47 PM +0200 8/24/08, Manfred Stede wrote:
>As everybody in the discussion seems to agree, there are other things
>going on in text besides constructing the argument / realizing the
>discourse purpose. One important thing is the thematic development,
>and I'd argue (and maybe not everybody agrees...) that once we decide
>to use RST trees to capture writer's purposes, we can't simultaneously
>capture thematic development with those same trees very well. cf. the
>discussion of ELABORATION by Knott et al. 2001, and others.

I can sort-of imagine 'constructing the argument / realizing the 
discourse purpose'.  The speaker wants to convey some information 
(semantic) or affect some attitude (interpersonal) and builds the 
discourse to do so, step by step.

I am confused about what 'thematic development' might be, as a thing 
on its own.  Isn't it the case that when one follows a purpose, one 
has to develop one's argument, and therefore one necessarily has  to 
introduce themes and rhemes and move to new themes, etc.?  That is, 
isn't thematic development an automatic effect of realizing one's 
purpose?

If the answer is yes, then it should be possible to show strong 
predictive correlation from discourse purpose structure to thematic 
development structure (insofar as the latter is not isomorphic to the 
former).  That is, given the former, one should by simple rules be 
able to predict the latter.  (Their differences might arise from 
syntactic or prosodic considerations, but not intentional ones.)

If the answer is no, then may I ask what is the difference between 
the kind of theme/rheme development introduced as an automatic 
side-effect of following one's purpose, and this other 'real' 
thematic development?  How do the two interact in order to decide 
which clause element becomes the theme in each new sentence?  On what 
basis does the speaker make thematic development decisions?  And so 
on.

(To me this latter case, in which thematic development is a truly 
independent thing, looks very problematic.  I'd love to learn more 
about it.)

Please note, in either case one would be able to annotate two 
separate layers, purpose-oriented and thematic.  In the former case, 
however, the thematic would be 'derivable' from the purpose-oriented, 
and not be a truly independent notation; its structure would be a 
homeomorphism of the purpose-oriented one.

You raise another interesting point:

>The systemic metafunctions discussed by Ed and
>John are probably the most thought-through attempt to provide a uniform
>and well-defined framework for any kind of multi-level idea. It does not
>map perfectly to the annotation practice I described above, though.
>Rather than going into that (this mail is long enough already, sorry!!),
>just two remarks: The interpersonal metafunction (as I understood it from
>Halliday) is not quite intended to capture claim-argument relationships, or
>is it? Similarly, I'm not so sure that the interpersonal/ideational
>distinction corresponds to the presentational/subject-matter distinction in
>RST (which is widely accepted in the community, and rightly so, I think).
>Finally, I'm not sure where a level of thematic structure would belong -
>there is overlap with the idea of "textual" but again it does not seem to
>be the same. Thus, to my mind, metafunctions are in principle on the right
>track but haven't exactly made it.

What precisely DOES the interpersonal metafunction capture?  If I say 
"all trees have roots", is this an ideational statement (a simple 
factual statement) or an interpersonal one (it's my opinion that all 
trees have roots)?  I don't know what Halliday said on this, but it 
seems to me that if one is going to cloak EVERY statement as a 
speaker opinion and hence Interpersonal, it makes the Interpersonal 
an empty concept.  So for me, it has always seemed that the 
Interpersonal only obtains when there is an explicit or implicit (but 
fairly shallow) reference to the speaker's or hearer's goals, 
opinions, capabilities, or mutual social relationship.  In more 
detail:
- goals: I (don't) want (to do) something / I (don't) want you to do
    something
- opinions: I believe this is good/bad / I believe this is true/false
- capabilities: I can/can't do this / I believe you can/can't do this
- relationships: I (dis)like you / you are (un)known to me / you (don't)
    outrank me

In that light, all claim-argument statements that are not purely 
factual, but that fall into one of these categories are 
Interpersonal.  But an argument as a whole can be constructed out of 
a mixture of statements from these categories as well as purely 
factual ones.  It's not always easy to know which of the two a 
statement is -- it's not always easy to determine is a statement of 
fact is truly a statement of fact or if the speaker is just 
pretending to be an expert -- but that's just the nature of the world.

Regarding the presentational vs. subject-matter distinction, this is 
something I frankly have never understood, but I am hungry and it's 
dinner time.

Regards,
E

-- 
Eduard Hovy
email: hovy at isi.edu            USC Information Sciences Institute
tel: 310-448-8731            4676 Admiralty Way
fax: 310-823-6714            Marina del Rey, CA 90292-6695
http://www.isi.edu/natural-language/nlp-at-isi.html