A minimalist inquiry into null subjects in child early grammar

Abstract This paper investigates null subjects in child early L1 grammar, grounding its explanation in the principles of computational efficiency and simplicity central to the Strong Minimalist Thesis. We argue that while the Extended Projection Principle – the requirement for clauses to have a subject – is universal, languages differ in how this requirement is met. Cross-linguistic variation between null-subject languages like Arabic and non-null-subject languages like English stems from how a potential null subject’s features and reference are identified and licensed. Drawing on Chomsky’s work on the I-language/externalization distinction, this study explores the different grammatical mechanisms that enable the recoverability of a null subject. In some languages, like Arabic, recoverability is achieved through rich verbal agreement. By contrast, in English and French, externalization pressures (such as phonological syncretism) and impoverished morphology prevent this licensing, rendering null subjects ungrammatical in the adult target. However, in early child English or French, specific information-structure conditions may license root TP structures that allow for null subjects. This investigation aims to provide a deeper understanding of how children, guided by principles like Grammatical Conservatism, acquire and use null subjects across these diverse linguistic contexts (including Agreement-based and Discourse-based interfaces).