Detail #168: Split Quirky Case / Split Differential Object Marking

Quirky case and differential object marking can of course be "split" in the sense that split ergativity or some other similar system can be split.

As for split DOM, Baltic Finnic sort of has that already: only non-negative verbs distinguish telic from atelic objects. However, seeing the negative verb as the 'typical', non-split context seems weird, and this might be why it's not reported as a split DOM all that much. 

As for split quirky case, that would be all that more interesting really - some verb that can take quirky case subjects/object only does so under certain circumstances - and picking the non-quirky subject/object indicates something as well in that circumstance. This makes it slightly more lexically restricted - given that quirky case generally signifies a lexically restricted set of (usually) verbs that require an odd case for their subjects or objects.

This can of course also go on for participles and the like. As an example I'll use a 'fake' Finnish where 'to have to', viz. 'täytyy' has Split Quirky Subjects (in real Finnish, the subject is invariably in the genitive). Let's also imagine that this split only happens in the transitive:

minu	-n		täytyy		syödä
1sg	-gen		must	(-3sg)	eat
I			must		eat

Note that the "3sg" is a sort of 'placeholder' - impersonal and third person verbs are marked the same in Finnish.

Let us now imagine that in past tense, there's a quirky subject thing going on, where the subject can be nominative as well - and this affects verb morphology too:

minä			täyty-i	-n	syödä		ruoka/ruuan*
I			must-past	(-1sg)	eat(telic)		food
I			had to		finish eating		the food

BEWARE: the above sentence is malformed Finnish; Anyone using google to find attestations of nominative subjects with this construction beware!

minun			täyty-i		syödä		ruoka
1sg gen			must-past	(-3sg)	eat(telic)		food
I			had to		finish eating		the food

What kind of a distinction could we have by this very restricted quirky subject split? Maybe something about how the obligation came about - or perhaps even more interesting, "minun täytyi" might imply that this was part of a causal chain with relevance in the presence, i.e. "I had to finish eating the food - and that's why I am late", whereas "minä täytyi" lacks that implication.

* The Finnish object is funny - whenever there's no nominative subject, a singular telic, non-negative object is in the nominative, otherwise in the genitive. (In the plural, it works slightly differently: the nominative and the accusative are identical, and thus "ruoat"/"ruuat" would cover both options.)