Principles and parameters

Introduction: Principles and ParametersThe Principles-and-Parameters (P&P) approach to cross-linguistic variation was first developed by Chomsky and his associates in the early 1980s (see in particular Chomsky (1981), and, for more general introductions, Roberts (1996), Baker (2001); see also discussions in §7.2, §13.5, §16.4.1, §28.2). The leading idea is that Universal Grammar (UG) contains an invariant set of principles associated with parameters which define the space of possible variation among actual languages. Taking the principles to be innately given, and the parameters to be triggered by salient parts of the primary linguistic data (PLD) for language acquisition, this approach was held to be a major step in the direction of explanatory adequacy (in the sense of Chomsky 1964), since language acquisition could be seen as setting the parameters of the native language on the combined basis of the innate UG and the triggering aspects of the PLD. To give a concrete, if rather simplified, example: we know that languages can be divided into those which have unmarked VO order, e.g. English, and those which have OV order, e.g. Japanese (see also the discussion of Romance and Latin in §27.3 below). On the classical P&P view, the notion of ‘verb’ is given by the universal theory of syntactic categories, the notion of ‘object’ is given by the universal theory of grammatical functions, and the idea that the two combine to form a VP is given by the universal theory of phrase structure. These are all taken to be reflexes of UG principles. But experience tells the child which order of O and V inside VP is the appropriate one, and so a child hearing Japanese sets the parameter to OV, while the child hearing English sets it to VO. Parameters describe what is variant in natural-language syntax, and as such they predict the dimensions of language typology, predict aspects of language acquisition and predict what can change in the diachronic dimension.