Detail #357: A Syntactically Split Alignment

Most split alignment systems only have split alignment in the case marking, and not really in the underlying syntax.  The split often also either correlates to the TAM of the verb, or to certain grammatical persons. I don't recall seeing any other actual cause of an alignment split, and I would really be interested in hearing about any other triggers for it.

However, that's not what I am writing this post about. This post is about a split in syntactical alignment based on a semantic distinction among verbs. I further find this particular split rather likely to occur.

The particular thing I'd think would cause an intransitive subject to align with an object syntactically is existentialness. Verbs such as 'exist', 'be' (when used existentially), be found, be seen (maybe), be attested, etc all seem to lend themselves well to prefer an ergative syntax.

The most obvious phenomenon to investigate would be gaps, and we can easily imagine a language where

berries exist and I eat

would parse as

berries exist and I eat [them]

however, we can then expect that coordination over many VPs should also yield ergative patterns:

berries existed and I saw and ate and tasted sweetberries existed, and I saw and ate [them] and [they] tasted sweet

This should not be permitted when all verbs are just 'plain vanilla intransitives'

*the berries were tasty and I saw and ate and tasted sweet
*the berries were tasty and *I saw and *ate and *I tasted sweet

Of course, when multiple VPs are chained like this, the later the existential verb appears, the harder parsing correctly will be. For this reason, the language might either forbid existential verbs to be on the right hand of coordinations, especially after more than two or so,  or have some kind of 'de-existential' form that is semantically, but not syntactically existential. (This could be achieved by reusing some other thing from the language - maybe force quirky case existential subjects? maybe use usually non-finite verb forms? maybe have the usual existential verbs lack congruence, but forcing congruence on them turns them into 'regular' verbs?

Detail #8: A gender-like thing but with verbs instead

A language where there are three or so classes of verbs. These classes differ in

• what affixes they take to mark different things
• what they mark (e.g. class I marks tense-aspect but no mood, class II marks tense, aspect and mood, but has a less fine-grained tense-aspect system, and class III marks tense, and every verb in it has inherent aspect that cannot be changed morphologically)
• details in the congruence system (class I has gender, person, number agreement for the subject; class II has no agreement, class III has person, number and gender agreement for subject, as well as a really minimal object-related agreement detail, as well as volition marking by means of reduced agreement)

They do not differ by 

• meaning - there's no set of meanings that unite all verbs in one of the class or exclude verbs from some class; auxiliaries can be found in all three. With these exceptions: all verbs of movement are class I verbs, all verbs of possession, exchange of possession and agreements and contracts are in class III.
• intensity, whether they are kinetic or not, transitivity, number of arguments in general, etc.

However, the classes also differ in some other ways:

• subject and object case; class II is somewhat ergative in behavior. Coordinations using nominative and/or accusative is permissible, though, for all classes.
• certain derivative affixes assign a derived verb to a specific class
• infinitives are marked for case according to what the auxiliary's class calls for

Several verbs can be finite in a clause, and which subjects and objects belong to which verb can be distinguished by case (as well as proximity to verbs, if ambiguity has to be counteracted by phrasing). The case distinctions are fewer in the plural than the singular, so this works best with singular subjects.