Correlates of War

The title of this article can be understood in three different ways. First, it is the name of a research project in quantitative history begun in 1964 at the University of Michigan, and still under way. Second, it means the extent to which a wide variety of factors rise and fall with fluctuations in the incidence of war: whether they correlate or covary with war, strongly or weakly, positively or negatively. And, third, it describes a research strategy by which we can make the transition from a stage in which the efforts to account for war were largely speculative and anecdotal to a stage in which well-articulated theoretical models can be subjected to the most rigorous scientific scrutinizing. Let me begin with a brief look at the intellectual history of the human effort to understand the ‘causes’ of war and thus to reduce its frequency or severity, or even perhaps to eliminate it entirely from the face of the earth.