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

Intuitively, the two segments differ only with respect to coronal-internal
specifications; but now they appear to differ also with respect to specification for
[coronal] itself. In effect, a single contrastive difference — [–anterior] versus no
specification for anterior — has turned into two differences. Moreover, there is
no actual contrast between the two segments as regards their coronality, so it is
odd that one should be specified for [coronal] while the other is not.
Avery and Rice (1989: 183) propose the Node Activation Condition (NAC)
for such situations. The NAC, given in (5.36), requires that Sanskrit plain
coronals be represented with a coronal node, as in (5.35c).
(5.36) Node Activation Condition (Avery and Rice 1989)
If a secondary content node is the sole distinguishing feature
between two segments, then the primary feature is activated for the
segments distinguished. Active nodes must be present in underlying
representation.
Though the NAC reduces the difference between plain and retroflex
consonants to the minimal feature by which they contrast, it does so at the cost of
introducing noncontrastive features and nodes into otherwise contrastive
representations. In this way feature geometry introduces ‘contrast from below’: a
feature (or node) is introduced not for contrastive purposes (contrast from
above), but to serve dependent nodes that require its presence. Whether the NAC
is required is ultimately an empirical question. The Contrastivist Hypothesis can
accommodate such ‘extra’ specifications if they are warranted. But developments
in feature geometry may make devices like the NAC unnecessary.
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