The quality of this book confirms that Ariel Rubinstein is one of the most important game theorists, and, more generally, theoretical economists today. His importance lies in his originality. He urges researchers to break out of established thought patterns. He opens up new lines of thought. He is willing to disagree with predominant views. All these qualities are reflected in the current book.

As their author readily acknowledges, some chapters of this book are loosely, but not tightly connected. Chapters 1, 2 and 3, however, have much in common. They are all based on the claim that the ideas of game theory can be fruitfully applied to the study of language. Reading and reflecting on this book has convinced me that this is indeed the case. The best evidence which I can offer is the fact that while reading the book I could think of many additional ideas in this area which appeared to me as promising research subjects. Some of these ideas will be indicated below. Given the limitations of space for this comment, and because of the coherence of chapters 1–3 I shall focus in my discussion on these three chapters.

The simplest game-theoretic model of language is described in chapter 2. A parable can capture the essence of this model: Exactly one of several boxes contains a prize which individuals A and B can share if they find it. Individual A, but not individual B, observes the box into which the prize is placed.