Economic Theory is used by the author instead of a title like Micro Theory or Price Theory because of his deep belief that there is only one kind of economic theory, not separate theories for micro problems, macro problems, non-market decisions, and so on. Indeed, the most promising development in recent years in the literature on unemployment and other macro problems has been the increasing reliance on utility maximization. Much of Becker's discussion is related to the market sector in industrialized economies, the principles being developed are frequently applied to other sectors and different kinds of choices. Economic analysis is essential in understanding much of the behavior traditionally studied by sociologists, anthropologists, and other social scientists. This is a true example of economic imperialism. The broad definition of economics in terms of scarce means and competing ends should be taken seriously and should be a source of pride to economists since it provides insights into a wide variety of problems.

Microeconomics, is the subject matter of these lectures. The lectures are emphatically, not confined to microeconomics in the literal sense of micro units like firms or households. Becker's main interest is in market behavior of aggregations of firms and households. Although important inferences are drawn about individual firms and households, the author tries to understand aggregate responses to changes in basic economic parameters like tax rates, tariff schedules, technology, or antitrust provisions.

It is important to choose the appropriate mathematical level of the presentation, especially since social science sophistication has improved in recent years. Beckerhas placed extended mathematical discussions in footnotes and appendixes. Practically all statements proved mathematically are also provided geometrically or verbally in the body of the text.