Ecological and Economic System Health and Social Decision Making

Abstract

All complex systems are, by definition, made up of a number of interacting parts. In general, these components vary in their type, structure, and function within the whole system. Thus a system’s behavior cannot be summarized simply by adding up the behavior of the individual parts. Contrast a simple physical system (say, an ideal gas) with a complex biological system (say, an organism). The temperature of the gas is a simple aggregation of the kinetic energy of all the individual molecules in the gas. The temperature, pressure, and volume of the gas are related by simple relationships with little or no uncertainty. An organism, however, is composed of complex cells and organ systems. The state of an organism cannot be surmised simply by adding up the states of the individual components, since these components are themselves complex and have different, noncommensurable functions within the overall system. Indicators that might be useful for understanding heart function — pumping rate and blood pressure, for instance — are meaningless for skin or teeth.