Opacity and cyclicity

Phonological opacity and paradigmatic effects (“synchronic analogy”) have long been of interest in relation to change, naturalness, and the phonology/morphology interface. Their investigation has now acquired a new urgency, because they call into question OT’s postulate that constraints are evaluated in parallel. Conceptually, parallelism is one of the basic and most interesting tenets of OT, and so there are good methodological reasons to try hard to save it in the face of such recalcitrant data. The price to be paid for it is the introduction of otherwise unneeded powerful new types of Faithfulness constraints, such as Output/Output (O/O) constraints, Paradigm Uniformity constraints, and Sympathy constraints, which have turned out to compromise the OT program very severely. The alternative to this approach is to abandon full parallelism in favor of stratified constraint systems. This has the compensating advantage of maintaining a restrictive and well-defined constraint inventory, as originally envisaged in OT. More importantly, it achieves some genuine explanations by relating the stratification motivated by opacity and cyclicity to the intrinsic morphological and