In this paper we present a simple and unified model in which a large variety of politico-economic systems may be represented and static comparisons, positive and normative, between these systems may be carried out. In principle, the model encompasses an infinite variety of political economies, but we focus on twelve salient cases, namely, five types of capitalism, two types of communism, two types of slavery, and three types of colonialism.

In § 1 we introduce our approach, specify the basic data (preferences and technology) we will be working with, and assemble the « nutshell » within which we will remain from there on. In § 2 we describe a dozen political economies and determine, for each, both their associated « positive » economic quantities, such as employment and output and the distribution of income between workers, capitalists and colonialists, as well as corresponding magnitudes, such as « communal surplus » and class members' utility levels, which form the basis for our analysis in the subsequent sections. All these are displayed as Table I, and the outcomes of the dozen political economies considered are identified in Figure I, which depicts the « nutshell » assembled in § 1. Then § 3 derives the preferences of workers, capitalists and colonialists (displayed in Diagrams I, II and III, resp.) regarding the politico-economic systems in question, determining a class conflict which arises, identifying the Pareto-efficient systems for all the coalitions of classes. In § 4 we rank our dozen political economies in terms of the respective communal surplus they generate, from which it becomes plain in which « revolutions » (changes in politico-economic systems) the winners may compensate the losers. Finally, § 5 closes our present study by indicating how it might be fruitfully extended.