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

[+back]. The addition of the feature [back] exiles the [+back] segments /a/ and
/u/ to the outer nodes, away from /i/ that had formerly connected them.
(2.24) Three-vowel inventory, features [high], [round], [back]
° • u
[+high]
i • ° inner nodes: [–back]
[–round]
[+round]
° ° outer nodes: [+back]
[–high]
a • °
It follows, then, that the pairwise approach to contrastive specification
fails in the simplest vowel systems, when all features are taken into account. The
reason that this simple fact has not disqualified it long ago as a theory of contrast
is that many analysts tacitly reduce the feature set to a minimal set. That is, if an
inventory is classifiable using a proper subset of the full set of features, then the
‘extra’ features are quietly discarded until the set is minimal, but still able to
distinguish every member of the inventory.
In such cases, the analyst chooses which logically redundant features to
delete and which to retain. Such a choice implies some notion of a hierarchy, and
is in fact a tacit use of feature ordering. Therefore, even an algorithm formulated
to remove redundancies from fully specified specifications must be
supplemented by some device that orders the redundant specifications so that
some take priority over others. That is, some notion of a feature hierarchy is
required even in a pairwise approach to contrastive specification. But if a feature
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