Mine, Yours, Ours, His, Hers, Its, and Don't Forget Theirs

Question

What exactly are the Indo-European predicative mine/yours/ours/his/hers/its/theirs forms, in terms of word class and inflection? Would they be considered the genitive (or even the dative) case of personal pronouns, a nominalized (or genitive) form of possessive adjectives, or something distinct?

Looking at German, the forms for the genitive, dative, possessive adjective, and predicative possessive are clearly distinct (e.g. genitive 'meiner', possessive adjective 'mein', dative 'meinem', and predicative 'meins'), though the genitive of personal pronouns is rare in modern German. There is some resemblance between the genitive case of possessive adjectives and the predicative forms; I kind of wonder if there might have been a progression of "It is [one] of my things" to "It is mine", but that's kind of tenuous.

In English they kind of look like the possessive adjective + -'s, but that's also pretty tenuous. Looking over Beowulf I kind of got the impression that in Old English the dative of possession was used for predicative possession.

As I understand it, the genitive of the personal pronoun or dative of possession would have been used predicatively in Latin, and I haven't heard of a dedicated predicative form.

Answer 1

My preferred analysis of the forms mine/yours/his/hers/ours/theirs is that they are possessive pronouns, whereas the forms my/your/his/her/our/their are possessive determiners. A determiner is an immediate dependent of a noun, whereas a pronoun is an immediate dependent of a verb or a preposition. In other words, one looks to cooccurence patterns as the basis for the classification. Note that I am assuming an NP-analysis of noun phrases, not a DP-analysis.

The analysis of N-ellipsis bears on this matter. One prominent approach to N-ellipsis is that ellipsis has indeed occurred. At least the noun has been elided, e.g.

 a. He watches my dog, and I watch his.

In this example, the ellipsis approach assumes that dog has been elided. On my preferred analysis, however, ellipsis has not occurred, but rather what is often a possessive determiner has become a pronoun. In other words, the form his is a direct dependent of the verb watch.

This explains the varying forms in part, e.g. your vs. yours, our vs. ours. The -s appears to accommodate a different position in the syntactic hierarchy. On this account then, there is no motivation to distinguish between a predicative use of these words and other uses, since the predicative use is the possessive pronoun (not the possessive determiner). Any time the form at hand is not the direct dependent of a noun, it is a pronoun.

The explanation works for German, as well, e.g.

 b. Ich mag sein Haus, und er mag meins  vs. *..,  und er mag mein  

    I  like his house, and he likes mine vs. *..., and he likes my. 

There is systematic variation according to whether the form is a direct dependent of a noun or not.

Thus to answer the question as directly as possible, I believe the forms mine/yours/his/hers/ours/theirs do not stem directly from genitive forms, and they do not stem directly from dative forms, but rather they are distinct forms that stem most directly from the possessive determiners (case neutral). They are particular forms that arose to accommodate a distinct cooccurrence pattern.