On syntactic and phonological representations

This paper argues that phonological representations are not trees, but strings structured through boundary symbols. Because trees are richer in information than strings, our main argument rests on a demonstration that tree-based phonology is too strong, in that it allows rules for which there is no empirical basis. We discuss three contrasts between syntax and phonology that can be understood if phonology lacks trees. The first is that syntax has recursive structures, whereas phonology does not. The second is that syntax allows nonterminal nodes with feature content (as a result of percolation), but that no convincing case can be made for the feature content of putative nonterminal nodes in phonology. Finally, syntactic dependencies are conditioned by c-command, while phonological dependencies are, by and large, conditioned by adjacency. The second and third difference between syntax and phonology can also be used to demonstrate that a tree-based phonology is too weak, in that independently motivated conditions on trees do not allow existing phonological rules.