The scope of logical expressions in child language

This thesis explores the way children choose to resolve certain kinds of semantic scope ambiguities. The aim is to answer two main questions: (i) which reading of scopally ambiguous sentences do children favour, if either? (ii) if children favour one reading, why do they do so? Several hypotheses have been put forward to account for what we currently know about children's scope preferences, suggesting different answers to (i) and (ii) above. The main contribution of this thesis is to reformulate one of these hypotheses to address some of its observed shortcomings, and to test the predictions of the new formulation on three sentence types that have not yet been investigated in the previous literature. These are sentences containing (a) the temporal conjunction before and disjunction (e.g. The dog reached the finish line before the turtle or the bunny), (b) negation and conjunction (e.g. The elephant did not eat both the carrot and the capsicum), and (c) the compound quantifier not every and disjunction (e.g. Not every princess took a star or a shell). Each of these sentence types gives rise to two possible scope interpretations, although languages can vary as to which of these readings is preferred. We present the results of three major studies (and two supporting studies) to determine which of the possible scope interpretations children prefer for each of these sentence types. Chapter 1 provides an introduction to the scope preference hypotheses. Chapter 2 looks at English- and Mandarin-speaking children's interpretative preferences for sentence type (a). Chapter 3 investigates children's interpretation of the pre-subject focus operator 'only'. These findings inform our experimental design in Chapter 4, which examines English- and Mandarin-speaking children's interpretative preferences for sentence type (b). Chapter 5 investigates children's interpretation of the universal quantifier 'every'. These findings inform our experimental design in Chapter 6, which examines English-speaking children's interpretative preferences for sentence type (c). Chapter 6 also explores how logical principles underpin the scope interpretations available in sentences (a)-(c), and whether children are sensitive to these principles. In Chapter 7, we discuss the implications of the findings for current accounts of children's scope preference and we offer answers to the two main questions of this thesis.