Constraint Symmetry in Optimality-Theoretic Syntax

As Sells (2001) has noted, few of the directional constraints thus far motivated in Optimality Theoretic Lexical Functional Grammar seem truly symmetrical in their application. It is clear that there are languages that attempt to align interrogatives, foci, and topics with the left edge of a clause (Wh-L, Foc-L, Top-L) and languages that attempt to align the head of a phrase with the left edge of that phrase (Head-L). It is less clear that Wh-R, Foc-R, or Top-R is well motivated. The question naturally arises --- are all syntactic constraints fundamentally asymmetric or are there constraints that operate symmetrically, with both left and right variants?

This paper explores one constraint, Consistency, that appear to have just such a symmetrical quality. As is well-known, languages fall primarily into two groups: canonically left-branching and canonically right-branching. In many languages, we see the effects of a Consistency constraint that limits the size and/or composition of material which appears on the non-canonical side of a head. This paper explores such Consistency effects associated with 1.) pied-piping with inversion in San Dionicio Ocotepec Zapotec (Otomanguean, Mexico) 2.) preposition deletion in (Semitic, Ethiopia), 3.) English prenominal adjectives, and 4.) English preposition inversion in sluicing context (swiping), and proposes a typology of Consistency restrictions.