For anyone interested in the core issues of first language acquisition and for those in search of research ideas for both first and second language acquisition studies, especially the interaction between syntax and semantics, this book is an obligatory read. This work, aimed at a general audience, is as interesting and intriguing for the beginner as it is for the expert. The theoretical issues are made tractable, the ethical issues are not forgotten, and the intricacies of the linguistic system are explained and illustrated by brilliantly simple examples. Although it is common for texts on acquisition to lag behind linguists’ formal understanding of different linguistic properties, Roeper’s book matches current thinking in formal linguistics with do-it-yourself ideas for experiments, which he calls explorations. In first reading this book with a group of faculty and graduate and undergraduate students, we found that each chapter provided enticing ideas to try with a few children and caused us to think about various ways to tweak Roeper’s experiments. This book made us feel like we ought to be thinking harder about language and acquisition. The enthusiasm and respect for the explanatory power of formal linguistics does not make Roeper’s book blind to the issues of language variation and social prejudice. In fact, he makes a strong claim about the need for science to inform policy and how we deal with human being issues. For Roeper, the scientist must always be a citizen as well.

This book is divided in four parts: After setting the stage (Part 1), Roeper discusses the development of the core grammar exploring the idea that a great deal of the developmental path can be explained by examining the internal logic of the linguistic computational system in its interaction with semantics. Roeper discusses the question of why certain relations or structures emerge before others—for example, why should possession emerge before coordination, in spite of the fact that and seems to be the easiest way to put two things together? The chapter on ellipsis (in Part 2) discusses how much information is left out of speech and how proficient listeners are or are not in recovering what was omitted. How do we know that John wanted someone to wash the dishes and so did I is very different from John wanted someone to wash the dishes and so I did? How does a child go about acquiring the ability to recover what is not there? This chapter provides the reader not only with new avenues of inquiry but also with clean evidence against purely input driven explanations. The discussion of ellipsis leads the citizen Roeper to examine the so-called easy books for children, which claim no more than six-word sentences. He shows how silly the idea of these shortened sentences can be if they are the result of massive amounts of ellipsis. Part 3 continues to follow children’s path constructing the grammar, but the focus is on intralinguistic and crosslinguistic variation from an acquisition perspective. The examples and discussion in these chapters are informed by Roeper’s work on the creation of a dialect-sensitive battery of tests for language disorders. Again, the citizen Roeper notes that linguistic prejudice is as irrational and damaging as regular racism. Part 4 comes full circle and explores the consequences of our understanding of grammar for the bigger picture of cognition (i.e., concepts and beliefs) as well as for morality and ethics. Throughout this book, Roeper discusses how blinding and dangerous simplified commonsense explanations may be when dealing with linguistic phenomena, and, here, he echoes the Nobel Prize winner José Saramago, who warns us against being blind to the fundamental issues.

In sum, this book is a great source of ideas for studies and experiments that will eventually lead to a much better understanding of language and language acquisition.