Second-class adjectives and their roots

[interprete]

Hello,

My Latin manual introduces second-class adjectives as receiving 3rd declension case endings, but establishes a distinction between fortis-type adjectives, and vetus-type adjectives.
My problem is that the manual (like all French textbooks apparently) bases this distinction on the root. It says that adjectives whose root ends in -i decline like fortis, while adjectives whose root ends in a consonant decline like vetus.

My question: how am I supposed to know how the root of an adjective ends? in fortis, on what basis should I consider that the i belongs to the root or, on the contrary, to the case ending -is?
Same with vetus, I vaguely remember that a root is evidenced by the genetive singular form, which here is veteris. So what tells me that the root is veter- and not -veteri, while for fortis it is forti- and not fort-?

Thanks...

 

[Notascooby]

In learning this stuff your chief and primary guide needs to be experience. For practical purposes you'll rarely if ever need to know this stuff. However If you want to find if it's an -i stem or a consonant stem it is the genitive plural you want to look at not the singular. An -i stem will generally have the genitive plural in -ium whereas consonant stems have -um. That -i is the stem.

The genitive plural of vetus is veterum as it is a consonant stem whereas the genitive plural of fortis is fortium which shows it is an -i stem.

According to Kennedy 48 -i stems originally had different case endings. Acc-im, ablative-i, acc pl-is.

Ibidem he says that unfortunately a lot of nouns have what he calls mixed stems having consonant stems in the singular and i- stems in the plural. As is the nature of these things there are always going to be exceptions that muddy the waters for those desiring clearly defined rules.

Looking to the gen plural will give you the best indication but it is not foolproof. Experience will be your best guide.

 

[interprete]

Thank you! It's funny that your approach is the exact opposite of what my textbook teaches.
According to my textbook, the very point of knowing the stem is to be able to predict how the adjective is to be declined, i.e. whether it's genitive plural is going to be -um or -ium.
But you're saying that in order to know the stem, I first need to know if the genitive is -ium or -um

 

[Notascooby]

Thank you! It's funny that your approach is the exact opposite of what my textbook teaches.
According to my textbook, the very point of knowing the stem is to be able to predict how the adjective is to be declined, i.e. whether it's genitive plural is going to be -um or -ium.
But you're saying that in order to know the stem, I first need to know if the genitive is -ium or -um

The rule of thumb is that nouns with a syllable more in the gen sg than the nom sg have gen pl in um.
Nouns with the same number of syllables in mom sg and gen sg have gen pl in ium.

 

[Pacifica]

According to Kennedy 48 -i stems originally had different case endings. Acc-im, ablative-i, acc pl-is.

The acc. pl. -is ending remained pretty common in both adjectives and i-stem nouns until after the classical period. In addition to being the usual ablative singular ending in i-stem adjectives, -i also survived as an alternative to -e in some i-stem nouns (e.g. civi and cive both occur as abl.; navi and nave, turri and turre are two other common pairs). It even stayed the only one in a very few nouns (e.g. siti, and the names of some rivers like Tiberi). Some of the civis-type nouns also have an alternative -im accusative singular ending. Civis itself doesn't, but navis and turris do (navim, turrim are common enough). Sitis-type nouns only have the -im ending, not the -em one (or if there are exceptions they're so rare I can't think of them).

unfortunately a lot of nouns have what he calls mixed stems

There was a lot of confusion, with i-stems and consonant stems influencing and borrowing from one another. You even find not so rarely the -ium ending in some nouns that, according to the rule usually taught (i.e. the one you mentioned about the number of syllables) should never take it: e.g. civitatium.

So all in all yes, I agree, the best way to go is probably to just see the usage.

As far as adjectives are concerned, those that don't behave like i-stem (that is, those that have their ablative singular in -e and don't have an i before the gen. pl. ending etc.) are very few. The only ones that come to mind right now besides vetus are pauper and dives. And even in those there's some variation in the ablative singular (at least veteri and diviti both occur).

 

[interprete]

The rule of thumb is that nouns with a syllable more in the gen sg than the nom sg have gen pl in um.
Nouns with the same number of syllables in mom sg and gen sg have gen pl in ium.

Thanks again, yes that's the rule my textbook gives for blinds, which it divided between parisyllabic and 'imparisyllabiques' (+urbs as an example of a false imparisyllabique) - I don't know if it's the same terminology in English.

@Pacifica thanks ! My course passes Latin off as an exquisitely regular language with clockwork grammar, but then reality comes back to bite you in the fundament.

PS . I know this doesn't show up on the forum's main page so may I point you to the other thread I posted in this same section? Thanks!