Positional Neutralization - Linguistics - University of California ...

durations would mandate strong raising toward [i], while longer durations would
necessitate less, possibly no reduction.
At no point in this discussion so far has the concept of contrast neutralization
played any role. It is nonetheless commonplace in the literature to see discussion of
vowels nearly neutralizing, or sometimes neutralizing, or gradiently neutralizing. For the
purposes of this study such characterizations are held to be meaningless. Neutralization
here refers solely to a phonological process whereby two abstract categories are merged
into one under certain conditions, resulting in a loss of contrast between the two. In a
situation such as that described above, in which we find duration-dependent reduction of
/e/ toward [i] in unstressed syllables, it is quite possible, and indeed often the case in
systems of positional neutralization (such as the Bulgarian UVR of /o/ toward [u]
described in chapter 2) that due to frequent contextual pressures the statistical
distributions of the realizations of two independent phonological entities such as /i/ and
/e/ will overlap significantly along some, perhaps all dimensions. This would mean in
effect that some percentage of the realizations of both phonological entities would be
phonetically ambiguous, the relevant tokens having a certain probability of belonging to
the distribution of either the one or the other phonological category. Two categories may
overlap in this way in a given set of positions (as Bulgarian /o/ and /u/ in unstressed
syllables), however, without implying that the contrast between the two has been
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