INTRODUCTION

Officially, heart disease and cancer together accounted for roughly 50 percent of deaths in the United States in 2006. These attributions are physiological explanations of death in that they focus on the most proximate set of causes, such as the failure of a crucial bodily organ. But, physiology alone does not provide much guidance to those seeking to live healthier lives. Doctors and patients would prefer additional information about what behaviors or characteristics led to the disease. Relevant questions about these more remote causes might include: are individuals genetically predisposed to the disease? Do certain activities or environments lead to increased incidence of disease? What can one do to treat the disease? These questions move us beyond physiology and into the realm of epidemiology, and to theory that connects the immediate cause of death with observable aspects of life. That too is our progression as we move from physiology (Chapter 4) to epidemiology (this chapter).

Chapter Four developed a theory of constitutional bargaining, which describes the mechanics by which constitutions enter periods of crisis in which they are under threat of renegotiation and, potentially, replacement. Here, we specify the empirical implications of the theory and identify the observable factors that affect the risk of constitutional death. The motive is the same as that of the epidemiologist who seeks to test assumptions about the physiology of disease by positing and then testing hypotheses about which kinds of individuals are more or less at risk.