The contrastive hierarchy in phonology 2009 Dresher.pdf - CUNY ...

This is because the procedure in (8.36) crucially refers to marking statements.
There is a universal marking statement that says sonorants should not be voiced,
and the procedure designates them as noncontrastive for [voiced]. But there is no
universal marking statement making fricatives and affricates voiceless. Thus, the
absence of their voiced counterparts is an ‘accidental’ gap, not a systematic one.
Calabrese proposes that the accidental absence of segments from a phonological
inventory does not determine the underlying specifications of the segments of
that inventory. Therefore, the unpaired fricatives and affricates can be treated as
contrastively voiceless.
While it gives the correct result in this case, this procedure seems to
contradict the intuitive notion of what it means to be contrastive in a system. The
SDA is a much simpler way of arriving at the same result while limiting the
evaluation of contrast to contrasts actually observed within the system in
question. In the contrastive hierarchy proposed in (8.14), the feature [sonorant] is
high in the hierarchy and divides the sonorants from the obstruents. Since the
sonorants are not contrastive for [voiced], they do not participate in voicing
assimilation. All non-sonorant consonants receive a contrastive value for
[voiced]. All that is required for the unpaired obstruents to be contrastively
voiceless is for the voicing feature to be high enough in the order.
Calabrese’s distinction between systematic and accidental gaps in an
inventory can be modeled in terms of the contrastive hierarchy. The difference
between gaps that are perceived as systematic as opposed to those that are
perceived as accidental is a function of where in the hierarchy the gap occurs.
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