Lothar von Trotha wrote: ↑22 Aug 2020 00:54
BUt what if they actually survived in daughter branches of PIE and became predominant over prepositions? Could they then supplant the disappearing case forms?
They could survive, sure. One of my own invented languages (Talarian, a descendant of Aryan (i.e. PIE)) is postposing. I'm not sure several postpositions that govern a single case would somehow supplant the case marker itself. Unless you're proposing that any given primitive case becomes divided into perhaps half a dozen new cases of which the postpositions simply become the new case markers?
Now, with Talarian, just about everything is postposed, from pronouns (pronouns per se and also topic/focus indicators) to postpositions per se (and they themselves can be doubled & preposed) to conjunctions and even other substantive roots.
Not all of these things govern a case, of course. -he (and) is probably one of the most commonly found postpositions, but it can be tacked on to anything. Including itself!
I don't think Talarian as it's now spoken would evolve to supplant case forms: those are still terribly useful. If you strike somebody
ffâcâ-ca, with a staff or wand, that's just the bare instrumental
-â. -com (with) has only a locative of accompaniment sense. A staff can stand
maka-com-he, with me (by which is meant, it's in my hand); but I can't strike somebody
ffâcâ-com-ca-he. That's just right out. At best, the post / peripositions amplify and focus the broad sense of the case ending.
So in Latin you would have
Marcus patrum libris dat > Marcos da libru patre a *(instead of "a patre"
Marcus mihi librum patris dat > Marcos mi da libru patre de (not "de patre")
Ovis equusque > ovis equus et
Well, -que doesn't govern a case. It's a conjunction. If you use "et", it would just continue as ovis et equus as it's done into the modern languages.
Otherwise, I count about 16 Latin prepositions that govern the accusative and almost as many govern the ablative. Are you suggesting almost 30 new cases be formed? And I'm supposing that the nominative, genitive, and dative (to my knowledge no prepositions ever govern them) would remain as is.
I don't know that the -m of the accusative would necessarily disappear. Me I think I'd probably argue that the new case marker would end up -mad. A medial -m- has much less cause or excuse to disappear than a final -m in Latin!
So you'd have a number of new cases: -mad, -mante, -mapud, -mecircum, -mecontra, -mextra, -min, -minter, -mob, -mper and so forth. All of which would be variations on the accusative. Interesting things will, no doubt, happen as we move into Vulgar Latin & Old French times. OF eventually loses final -d, so petremad might end up perema. Patremecircum might end up perecirque. perementre, peremper.
Eventually, phonological change would wear away some of these. peremin & perema are in danger of coalescing.
I wonder: might -mente gravitate towards the new nominal declension as a form of ablative; or would it remain among the adverbes?