THIS BOOK is a study of military deterrence as it has been used at various times and places throughout twenty-five hundred years of history. We first hope to shed some light on the powers and limits of military deterrence as a strategy in international politics; but, more important, we offer this book as a working model of the cross- historical survey. The cross-historical survey is a method of comparative historical research, a sample survey whose unit of study is a particular historical period of a particular society. Our idea is to study comparatively dozens or even hundreds of such units and to draw statistical correlations from them. The cross-historical method we propose is simply an application of the well-known cross-cultural survey method of anthropological research to the comparative study of history.
We beg every reader, and especially every trained historian, to bear in mind the crucial distinction between our goal and that of the historiographer. A historiographer constructs a theory that will interpret events in a particular historical period at a particular time and place. We here are trying to find patterns common to many different times and places. Our data are not the primary sources of the historiographer but rather the patterns governing each particular historical period. By noting how and under what conditions these patterns vary from one period to another, we, as comparative historians, hope to arrive at a statement of "laws" governing these separate sets of patterns. This principle is known to anthropologists as Goodenoughapos;s Rule (see Goodenough 1956:37).
We hope that this working model may interest those who want to study written historical records in search of general regularities