Così fan tutte and Italian 3rd pers plural mark -no

[merijn]

I have two related questions about Italian.
1. In the name of the opera the form "fan" is used, but it is "fanno" in standard Italian, right? So is "fan" poetic Italian or dialectic and is the drop of the -o also allowed in those dialects/registers with other 3rd person plural forms?
2. The Italian -o in the 3rd person plural -no is not a continuation from anything Latin. From what I understand the standard explanation is as follows: 1. people added the -o to 1st person singular copula son to get sono, 2. people extended this -o to the 3rd person plural copula son that it became sono as well. 3. then it was extended to all other 3rd person plurals. It seems to me that a simpler explanation is that Italian came to have a ban on word-final consonants (except for phonologically dependent words such as articles and prepositions) and the -o was added as epenthesis. In the past I have searched to see if there were people who agreed with me, and at the time I did find one article where my scenario was argued for. However, that was not the main point of the article, it might even be in a footnote and the article wasn't about diachronic change anyway IIRC (I think it was about epenthesis in different Italian dialects). Does anybody know if there is any evidence what the correct analysis is?

[Legion]

A ban on final consonant would not by itself be enough to explain the -no ending, for the simple reason that orinally the Latin 3pl ending -nt was lost in *all polysyllabic* verbs. Evidence of this loss is preserved in several paradigms, notably the preterit of a number of irregular verbs:

habere > avere

habui > ebbi
habuisti > avesti
habuit > ebbe
habuimus > avemmo
habuistes > aveste
habuerunt > ebbero

This -ro ending has further been analysed as another 3pl mark and spreaded concurently to -no, and eventually became the default marking in the subjunctive imperfect for all verbs:

cantare > cantare

cantavissem > cantassi
cantavisses > cantassi
cantavisset > cantasse
cantavissemus > cantassimo
cantavissetis > cantaste
cantavissent > cantassero

This also explains why verbs like "fare" and "avere" have a geminate -n- in the 3pl present form (fanno, hanno), because those received the analogical -no ending on top of an already present final -n which they had preserved by virtue of being monosyllabic.

This isn't that surprising, for comparison it's theorised that the 1pl -ons ending of French originally spreaded from a handful of verbs that ended in -umus in Latin (sumus, possumus).

As for the first question, vowel elision in Italian seems to be tied to archaism and/or poetry. If you read Dante, it is *full* of vowel elisions, not only word finally, but word initially as well!

"Gran duol mi prese al cor quando lo 'ntesi
però che gente di molto valore
conobbi che 'n quel limbo eran sospesi."

"Great grief seized on my heart when this I heard,
Because some people of much worthiness
I knew, who in that Limbo were suspended."

gran < grande
duol < dolore
cor < cuore
'ntesi < intesi
'n < in