Phase cancellation by external pair-merge of heads

As Chomsky (2004, 2005) notes, a theory with set-Merge allows this operation to apply in two different ways, externally (to two separate objects) and internally (one object contained within the other). Here we extend Chomsky's form of argument to pair-Merge; i.e. in the absence of some stipulation preventing it, it too can apply in two ways: internally and externally. We will argue that external pair-Merge of heads overcomes a paradox concerning bridge verb constructions. In the final section we note that external pair-Merge of heads is, in effect, a "presyntactic" morphological ("word formation") rule entailed by current syntactic theory. The extent to which the standard theory of morphological operations can be subsumed by external pair-Merge of heads, further unifying syntax and (aspects of) morphology is left for further research.