THEORY: Case systems and Ergativity

Recently, I've been wondering something about the case
system I've been building for Phaleran, which is a split
ergative system.  The question centers around my "diergative"
case, which is the case for the subject of ditransitive verbs,
verbs requiring two objects:  what would motivate the
creation of such a case?

A little context:  in Phaleran, all verbs must inflect according
to transitivity, whether intransitive, transitive, or ditransitive
(stative transitivity receives the null morpheme).  So, there is
already a precedent within the syntax for distinction being
made between (mono)transitive verbs and ditransitive verbs,
but I'm not sure why there would be any reason for that same
distinction to leak into the noun system.  I have a suspicion that
the core cases would see no reason for making a distinction,
because the transitivity of the verbs never intersects -- that is,
there is never an instance where you would need to distinguish
within the same context between an ergative case noun and
a diergative, because the verbs themselves are either transitive
or ditransitive, but not both.

To my credit, I suppose, there are (a very few) languages
out there that distinguish between three core arguments of
subject of an intransitive verb, the subject of a transitive verb,
and the object of a transitive verb, so on that analogy, I might
say that even if there is no strong motivation for the creation of a
wholly new case without precedent, I could go ahead and do
it because of the way Phaleran verbal transitivity works.

So, what do y'all think? Does any of this make any sense?

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Tom Wier <artabanos@...>
ICQ#: 4315704   AIM: Deuterotom
Website: <http://www.angelfire.com/tx/eclectorium/>
"Cogito ergo sum, sed credo ergo ero."
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