Innateness and Parameter Setting

There have been major advances in linguistic theory in the past 50 years, and some of them have led to corresponding advances in understanding how children acquire language. Advances on both fronts resulted from the shift from rule-based theories of grammar in the 1960s and early 1970s, to the principles and parameters theory of the 1980s and 1990s, and its descendant, the minimalist program. According to the principles and parameters theory, children are not expected to accrue individual rules governing the local language, as had been supposed using earlier theories of syntax.

The principles and parameters theory supposes that children are biologically fitted, as part of the human genome, with a universal grammar. Universal grammar contains the core principles of language, [Page 414]that is, principles that are manifested in all human languages. These principles established the boundary conditions for grammar formation. Children were not expected to deviate from these principles in the course of language development. In addition, universal grammar spells out particular ways in which human languages can vary. These points of variation are called parameters.

Once parameters were entered into the theory of universal grammar, many cross-linguistic differences that had previously been assumed to be learned were reconceived as innately specified properties of human languages. So parameter setting is largely a matter of genetic specification, along with a minimal, but crucial, contribution from the environment. Because both the principles and parameters of universal grammar are innately specified, the principles and parameters theory is a “nativist” approach to language acquisition, to be contrasted with “nurture” approaches, which view language acquisition as largely the product of children's experience. The principles and parameters theory enabled researchers in child language to formulate and evaluate far-reaching predictions about the course of language acquisition, including predictions that were not consistent with experience-based accounts. This entry ends with a sample of the kinds of insights into child language acquisition that have been achieved within the principles and parameters theory.

The introduction of parameters was designed to make language learning easier. This advanced the theory of universal grammar along its stated goal of explaining children's rapid mastery of human language. Parameters were seen to reduce the role of experience in children's acquisition of human languages. Parameter setting was seen to initiate radical changes in child language. Instead of piecemeal acquisition of specific constructions, as advocated by experience-based accounts of language development, acquisition was seen to involve the mastery of clusters of linguistic phenomena, all in one fell swoop. The metaphor that was often coupled with descriptions of parameter setting was that of a switch, as in a circuit box. The learner set the switch one way or the other in response to “triggering” experience. If the switch was set one way, then the child's grammar assumed one format; if the switch was set the other way, the child's grammar assumed a different format.

Although experience was a prerequisite to setting parameters, it is important to appreciate that parameter setting did not have the character of learning. Instead, parameters were assumed to be set reflexively. Reflexive responses by a species to particular inputs are characteristic of genetically determined acquisition in any domain. Similarly, the expectation was that parameter values were triggered or fixed by experience, as in one-trial learning. This accounted, in part, for the rapidity of children's acquisition of language, as compared with other cognitive skills such as the ability to learn to count, or to draw, or to play a musical instrument.

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