Appositive sentences and the structure(s) of coordination

Coordination is not a unitary phenomenon: as far as binding and scope of external elements are concerned, appositive coordinate sentences may differ from their nonappositive integrated counterparts in the same way as appositive relatives differ from restrictive relatives, suggesting that different configurations are involved in appositive vs. non-appositive sentences. The Set-Merge (Kayne 1994) and Pair Merge (Munn 1992) proposals for dealing with coordination, although relevant, are not enough to distinguish appositive from non-appositive sentences. The crucial distinguishing property of appositives is their parenthetical status: they are adjuncts affected by a feature specifying their parenthetical nature. This allows the computational system, which operates bottom up and according to an Earliness Condition (Pesetsky 1989, Chomsky 2001), to interpret them as autonomous CP phases, to be transferred to the Interface components before the phases they are inserted in, thus preventing c-command effects from external elements at SEM.