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Bracketing paradox

MORPHOLOGY: a situation in which the morphological structure of a word which one would like to propose for semantic reasons does not correspond to the structure one would like to propose for phonological reasons. Hence, a situation in which morphophonological structure and semantic structure are not isomorphic. The existence of bracketing paradoxes is closely associated with level-ordering theories such as Pesetsky's (1979) and Kiparsky's (1982) theories of Lexical Morphology/Phonology. These theories propose morphological structures on the basis of level-ordering which are sometimes in conflict with the semantic structure. EXAMPLE: A well-known case of a bracketing paradox independent of level-ordering (see Level Ordering Hypothesis) involves the English comparative suffix -er and the negative prefix un-. In this case the phonological argumentation derives from a well-known restriction on the attachment of -er. This suffix is subject to the following constraint: it may attach to monosyllabic adjectives, and a small class of bisyllabic ones with a light final syllable, while it may not attach to adjectives with two or more heavy syllables. Compare (i):

(i)	blacker,   softer,     poorer,      nicer
	happier,   luckier,    heavier
       *directer, *complexer, *eloquenter, *importanter