Development

To encompass fundamental aspects of physical and human nature, economic theorists must commit themselves to a dynamic, evolutionary point of view. In so doing, it is unlikely that a single unifi ed framework will serve the purpose. As in physics, distinct theoretical relationships have to be developed for the distinct levels at which action can be measured. If we take the individual to be the basic atom of economic phenomena, then the micro theory is concerned with what, why, and how people choose. At the macro level is the economics of a nation based on indexes of aggregated micro variables: GDP, total investment and consumption, measures of total capital and productivity, population, working age population, the employed and unemployed, total government spending, and the total money supply. In between lies the theory of organizational structures, households, business fi rms, and government agencies. The explanation of behavior at this level is in between the micro and the macro, thus, sometimes referred to as meso-economics.