3 - Why the ultimate solution is unlikely to be purely syntactic

Summary

Why should rules which adjoin terms to the right side of a variable be upward bounded, and not those which adjoin to the left of a variable? Why should it be that chopping rules, feature-changing rules, and unidirectional deletion rules share the property of being subject to the constraint, to the exclusion of other rules? Why should there be a difference between unidirectional and bidirectional pronominalization? Why should it be that the constraints are all “downward-oriented” – that is, why should it be that there are phrase-marker configurations that prevent elements indefinitely far below them from undergoing various syntactic operations, whereas there are no configurations which affect elements indefinitely far above them? Why should complex NP's, coordinate nodes, sentential subject clauses, and NP's on the left branches of larger NP's all function the same in defining islands?

(Ross 1967:291)

With these questions Ross concluded his seminal study on constraints on variables in syntax. All these questions are facets of the questions many linguists have pondered since then: Why islands?, and Why these islands?

These are the questions I would like to address in this chapter and the next, the most tentative part of the whole book; the most minimalist oriented as well, given that Ross’s questions just quoted are really about the design properties (‘why-questions’) of the language faculty.