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

The specifications derived from feature ordering do not omit all logically
redundant features. In the ordering [nasal] > [voiced] (2.5), /p/ is contrastively
specified as [–nasal], even though this specification is logically redundant, as we
have seen. And in the order [voiced] > [nasal], the value [+voiced] for /m/ is not
omitted, though it, too, is logically redundant.
The concept of contrast that emerges from feature ordering, then, is not
based on logical redundancy as defined in (2.11). Nevertheless, in any particular
feature ordering some features are defined as redundant (equivalent to those
features not designated as contrastive). To avoid confusion, let us call this type of
redundancy system redundancy and define it as in (2.12).
(2.12) System redundancy
The feature specification [F] is system redundant iff it is not
contrastive in terms of the method used for determining which
features are contrastive in an inventory.
System redundancy is relative to a particular method for designating
features as contrastive, whereas logical redundancy is fixed for a given inventory
and set of features. Since a specification that is not logically redundant is not
predictable under any procedure, it follows that the specifications designated as
system redundant in any system of contrastive specification will also be logically
redundant. The converse does not necessarily hold: a specification may be
logically redundant but not system redundant, as we have seen. Many
discussions of redundancy in phonology fail to distinguish the two types of
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