This book is perhaps the most stunning available demonstration of the explanatory power of the parametric approach to linguistic theory. It is akin, not to a deductive proof, but to the discovery of a footprint in a far-off place which leaves an archeologist elated. The book is full of intricate reasoning, but the stunning aspect is that the reasoning moves between not only complex syntax and diverse languages, but it makes predictions about what two-year-old children will assume about the jumble of linguistic input that confronts them. Those predictions, Hyams shows, are supported by a discriminating analysis of acquisition data in English and Italian. Let us examine the linguistic context for a moment before we discuss her theory. The ultimate issue in linguistic theory is the explanation of how a child can acquire any human language. To capture this fact we must posit an innate mechanism which meets two opposite constraints: it must be broad enough to account for the diversity of human language, and narrow enough so that the child does not make irrelevant hypotheses about his own language, particularly ones from which there is no recovery.
That is, a child must not posit a grammar which permits all of the sentences of a language as well as other sentences which are not in the language. In a word, the child must not create a language in which one cannot make adult discriminations between grammatical and ungrammatical.
1. Linguistic Theory and Syntactic Development.- 1. Introduction.- 2. A Parameterized Theory of UG.- 3. An Overview.- 3.1 A Note on Methodology.- 4. The Theory of Grammar.- Notes.- 2. The Null Subject Phenomenon.- 1. Introduction.- 2. The Structure of INFL.- 2.1 Rule R.- 3. Null Subjects and the Identity of AG.- 3.1 The Properties of PRO.- 3.1.1 Control of AG/PRO.- 3.1.2 Arbitrary Reference of AG/PRO.- 3.1.3 The Auxiliary Systems of Italian and English.- 4. Summary.- Notes.- 3. The AG/PRO Parameter in Early Grammars.- 1. Introduction.- 2. Null Subjects in Early Language.- 2.1 The Avoid Pronoun Principle.- 3. The Early Grammar of English (G1).- 3.1 The Auxiliaries in Early English.- 3.2 The Filtering Effect of Child Grammars.- 3.2.1 The Semi-Auxiliaries.- 3.2.2 Can't and Don't.- 3.3 G1 and the Syntax of Be.- 4. The Restructuring of G1.- 4.1 The Triggering Data.- 4.2 The Avoid Pronoun Principle in Child Language.- 5. Summary.- Notes.- 4. Some Comparative Data.- 1. Introduction.- 2. The Early Grammars of English and Italian: A Comparison.- 2.1 Postverbal Subjects.- 2.2 Modals in Early Italian.- 2.3 Italian Be.- 3. Early German.- Notes.- 5. Discontinuous Models of Linguistic Development.- 1. Introduction.- 2. Semantically-Based Child Grammars.- 3. Semantically-Based Grammars: Some Empirical Inadequacies.- 3.1 Evidence from Polish and Hebrew.- Notes.- 6. Further Issues in Acquisition Theory.- 1. Summary.- 2. The Initial State.- 2.1 The Subset Principle.- 2.2 The Theory of Markedness.- 2.3 The Isomorphism Principle.- 3. Instantaneous vs. Non-Instantaneous Acquisition 168 Notes.- Index of Names.- Index of Subjects.