In the preface the author outlines his view of the philosophy of science which, he says, underlies the essays of this book. It's an interesting set of ideas which covers the social sciences and biology and even touches a little bit upon the physical sciences. But these essays have been written independently of each other and this greatly reduces the overall coherence of the book. The guiding philosophical ideas presented in the preface are completely lost for long stretches of the book when the author delves into game theory. But it is nevertheless a pleasure to read an author who exhibits such a wide range of learning across different disciplines and distills the key part of complex arguments into a clear conclusion. I particularly liked the argument that there is no place for functional explanation in the social sciences. The author provides a nice formalization of the criteria that a true functional explanation would have to meet.