absolutive

The idea would be that neuters can't be agents and are therefore always absolutive.

In Classical Nahuatl, non-possessed nouns would take the absolutive case with -tl for nouns ending in vowels, and -tli for nouns ending in consonants.

Ergativity is specifically when the transitive subject (‘ergative’ argument) is treated differently to the transitive object/intransitive subject, which are treated the same way (‘absolutive’ argument).

For the purpose of inflicting severe bouts of pain in the rear orifice, give Basque (an absolutive-ergative language) or Georgian (a Kartveli language with the split ergative) a go.

What about languages with ergative-absolutive alignment?

I was under the impression that the unification of nominative and accusative case for neuters in Indo-European languages was indeed felt to derive from an ergative-absolutive distinction in proto-Indo-European.

I personally quite like Deal’s ‘ergative’ and ‘absolutive properties’ [0] as a first attempt; but I haven’t yet seen Lazard and Haspelmath, so I should look into that more.

We call the grouping of intransitive argument+transitive object the ‘absolutive’, and the transitive subject by itself the ‘ergative’; thus, a system like this, where the intransitive argument behaves the same as the transitive object, is called ‘ergative–absolutive alignment’.

Some of those options people may realize without exposure to the particular languages, but others -- such as, say, ergative-absolutive alignment (not that I'm suggesting that's a good option to use) -- they won't.

It has an ergative–absolutive alignment, compared to the nominative–accusative alignment of its surrounding languages; it has >10 cases with case-stacking, whereas European languages have ~6 cases without stacking; it has polypersonal agreement, whereas verbs agree with the subject only in most European languages.

In Basque, as with most European languages, this is indicated through special ‘case-markers’, usually suffixes: ‘-a(k)’ for absolutive argument, ‘-ak/-ek’ for ergative argument, ‘-(e)(t)an’ for location, ‘-(a)(r)en’ for possessor, and so forth.

Edit: yes, it's a suffix (for Classical Nahuatl): "Non-possessed nouns take a suffix called the absolutive.

Can you give examples of what a "ergative–absolutive alignment" looks like, or case-stacking?

> Can you give examples of what a "ergative–absolutive alignment" looks like, or case-stacking?

For example, proto-Indo European had Nominative Accusative alignment, and was highly inflected, but modern English is almost completely uninflected, and Hindi has Ergative-Absolutive alignment for some tenses.