ABSTRACT
In human languages, a phrasal unit that is interpreted thematically at Logical Form (LF) as occupying one syntactic position may occur overtly in Phonetic Form (PF) in a different position, a phenomenon referred to as the displacement property As Chomsky has noted (1995c:221-22), this property appears to be unique to human languages, especially in contrast to artificially constructed formal systems such as logic (in its variety of formulations) and so-called computer languages. It has been a constant focus in the study of modern generative grammar from the outset. Within the Principles and Parameters framework of the past two decades and more particularly within recent refinements of the Minimalist Program, attempts to discover what motivates this property have identified three potential factors: Case, agreement, and the requirement that certain functional categories must have syntactically realized specifier phrases. For example, the displacement that occurs in the English passive construction in (1) below could be motivated in terms of: (i) Case: the nominative (NOM) pronoun must move to the specifier position of the clause (headed by the functional category T(ense) and hence Spec-TP) to be licensed; (ii) Agreement: the pronoun must move to Spec-TP to establish agreement with the passive auxiliary was; and (iii) the property of the functional category T, which requires that the pronoun move to create Spec-TP.
