> The major objection I would have to it (*i, *u, *&, *a) is, that to
my way
> of thinking, it is asymmetrical: one height level for front and back
but two
> heights for central.
Actually, it has an unusual degree of symmetry. 4 vowel systems are
usually more asymmetric. For yet more examples, we have the
Proto-Austronesian system of /a, e, i, u/, and the Cree system, with
length contrasts, of /a, e, i, o/. Indeed the latter system seems
quite widespread in Canada.
Richard.
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It can be solved if we conclude
that Ablaut-joker *& is /o/
and *a is /e/.
So that we have a nice system
open o (Joker) versus e (a)
closed u versus i
Arnaud
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