Accessibility to universal grammar in child second language acquisition.

Abstract

The present study examines the evidence for accessibility to Universal Grammar (UG) in the interlanguage of four children (two Spanish speakers, a Japanese speaker, and a French speaker) acquiring English as a second language. Specifically, the study investigates whether these child second language (L2) learners had access to a posited principle of UG, the Morphological Uniformity Principle (MUP) proposed by Jaeggli and Safir (1987). The MUP provides a unified linguistic account of apparently disparate language facts--null subjects and verb inflections. The MUP states that null subjects are licensed only in languages which have uniform verb paradigms that is, either all the forms or none of the forms are inflected. Examples of such languages are Spanish, Italian, Japanese and Chinese. Languages such as English and French, which have non-uniform verb paradigms (i.e. irregular inflections), do not license null subjects. Certain precise and testable claims for language development are implied by the MUP. Specifically, the MUP predicts that null subjects should occur only in those child grammars which have morphologically uniform verb paradigms but not in those which have morphologically non-uniform verb paradigms. Hyams (1986, 1987) and Guilfoyle (1984) among others, have claimed that the null subject phenomenon is a universal property of child language. The present research tested Hyams' and Jaeggli's predictions in the ILs of the four child subjects. The findings do not indicate any strong evidence for child L2 learners' accessibility to the MUP. The claims for a Universal status for the MUP are thus questioned. It is argued that alternative explanations based on a combination of perceptual factors and the nature of the L1 can account for the occurrence and non-occurrence of null subjects in the IL of the three subjects who did not support Hyams and Jaeggli's claims. Individual variation, arising from three major factors, would also partially explain the differences observed in the IL of the four subjects. The findings of the study have several implications for L2 learners' accessibility to UG. A major implication relates to the problems involved in successfully addressing the question of access to UG in the L2. Possible lines of investigation, which are intended to overcome these problems, are proposed for future SLA research. (Abstract shortened with permission of author.)