> > >P.S. I would also be interested on peoples' ideas on the
> > >Germano-Balto-Slavic "m" in the dat.ins. pl. cases, vs. the "bh" in
> > >the
> > >rest of IE.
> >
> > Well, like you say, the wave model explains this well as a local
> > innovation.
> > Perhaps influenced by the gen.pl.?
>
> Thanks for the suggestion. What I have always found perplexing
> is the change /bh/ to /m/, which is not a regular phonological
> transformation from IE in any of these languages (although we
> see /b/ mutating to /m/ elsewhere in IE under certain situations,
> such as Gk. 'brotos' or the OIr. 'mna^h', genitive of 'ben'.)
> Thus, it doesn't seem to be strictly a phonological change,
> but perhaps analogical, etc. Your suggestion of an influence
> from the genitive plural is exactly the type of idea I was
> looking for. Is there any reason, based upon semantics, that
> the genitive should influence the dative or instrumental?
> The genitive seems more closely aligned with the ablative
> semantically (and was often combined with it in the daughter
> languages). Of course, the /bh/ occurs also in ablative plurals.
I seem to recall having read somewhere in a footnote that someone has suggested that the dative and ablative plural originally were distinct in form, i.e. that one of them had *m, the other *bh. Does anyone know who/where, or have I just dreamt it?
If we take this suggestion seriously, what are the odds of finding out which one had *m and which one *bh? (We may safely assume that instrumental had *bh.) No IE branch has an ablative form in the plural that differs from the dative (apart from Hittite, which, however, has an ending of its own, the same as in the sing.). Italic and Indo-Iranian are useless, since both preserves dative and ablative as distinct cases (though not formally in the plural). Germanic isn't very helpful either, since dative and ablative merged both formally and functionally. In Balto-Slavic, however, there are both formal and syntactical indications that the ablative merged with the genitive instead. This might be considered an argument that dative had *m, which was preserved, whereas the old ablative plural ending was lost in favour of the genitive plural ending (somewhat like in Greek). If it had been the other way around, dative *bh and ablative *m, the dative -mU/-ms/etc. would, of course, be more difficult to explain. The assumption of originally distinct ablative and dative plural forms also makes things easier than if we assume, e.g., levelling between instr. and dat.(/abl.) pl. in both the *m-area and the *bh-area, or in several different languages (cf. Beekes' Introduction, p. 118).
However, how do we explain *m in the instrumental? Back to influence from the genitive ... Or could it be influence from the dual, where all three cases (as far as we know) where identical? And: why did ablative and dative merge in so many languages?
Also, does anyone know of any evidence for (traces of) a distinct instr. pl. form in Germanic besides Old English thae^m with i-umlaut (*toimis instead of *toibhis), or any other explanation for the Old English form?
Urban Lindqvist