This can be entered as a plea of guilty: I am trying to get the message
across that "ablauting o" is not a single concept.
The "thematic vowel" shows an alternation between /o/ and /e/, not
connected with the accent, and only seen in stem-final position.
The causative has -o- always unaccented; in some specific root structures
the -o- is not present and we have instead the "iterative" type (which
however does have -o- if the root structure allows it).
The perfect has an -o- which appears only under the accent, while the
unaccented variant has zero.
These three are totally different. There is therefore no sense in
combining their o-variants into a common concept of "ablauting o". The
mere fact that they are all unstable certainly be enough to classify them
as "precisely" the same.
Jens
On Thu, 25 Sep 2003, P&G wrote:
[...]
> This needs a longer answer than I have time for, but at least threee of
> these precisely are the ablauting -o-:
> (2) the thematic vowel
> (3) the -o- vowel of causatives-iteratives
> (4) the -o- vowel of perfects