Economic Imperialism

Economics is not only a social science, it is a genuine science. Like the physical sciences, economics uses a methodology that produces refutable implications and tests these implications using solid statistical techniques. In particular, economics stresses three factors that distinguish it from other social sciences. Economists use the construct of rational individuals who engage in maximizing behavior. Economic models adhere strictly to the importance of equilibrium as part of any theory. Finally, a focus on efficiency leads economists to ask questions that other social sciences ignore. These ingredients have allowed economics to invade intellectual territory that was previously deemed to be outside the discipline’s realm. Edward P. Lazear Economic Imperialism July, 1999 Kiger (1963). Note that the current Allied Social Science Association (ASSA) is a different organization from the one the spawned the AEA. 1 By almost any market test, economics is the premier social science. The field attracts the most students, enjoys the attention of policy makers and journalists, and gains notice, both positive and negative, from other scientists. In large part, the success of economics derives from its rigor and relevance as well as from its generality. The economic toolbox can be used to address a large variety of problems drawn from a wide range of topics. In earliest times, economics was not distinct from other social sciences or even philosophy. Aristotle and Plato discussed economic issues in the context of social philosophy. Adam Smith, Ricardo, and Malthus analyzed economic factors in broader contexts than most economists do today. The American Economic Association itself was hewn from the societies of other fields. The AEA was created as a joint effort of the American Social Science Association and the American Historical Association for the purpose of encouraging economic research.1 At least during the last four decades, economics has expanded its scope of inquiry as well as its sphere of influence. Neither luck nor the inherent charm of economists is responsible for the change. Rather, the ascension of economics results from the fact that our discipline has a rigorous language that allows complicated concepts to be written in relatively simple, abstract terms. The language permits economists to strip away complexity. Complexity may add to the richness of description, but it also prevents the analyst Edward P. Lazear Economic Imperialism July, 1999 Rigor need not take the form of mathematics, but much of economic rigor relies on its mathematical precision. Although many economists of earlier years were accomplished mathematicians, Samuelson (1947) made mathematical economics available to the profession at large. Becker and Murphy (2000) argue that when social feedback effects are sufficiently strong, the maximizing individual will not be sensitive to the traditional variables of price and income. As a result, it will appear as though individual behavior is dictated by society. They argue that a more fruitful way to think about this is to allow for individual maximization with strong social interaction effects. In this way, equilibria can be understood and the nature of the result and feedbacks can be studied and predicted. 2 from seeing what is essential.2 Our rigorous language can be used in many ways, but over the years, three themes have become fundamental in economics. First, economists assume that individuals engage in maximizing, rational behavior. Second, economics adheres strictly to the importance of equilibrium as part of any theory. Third, economists place a heavy emphasis on a clearly defined concept of efficiency. The starting point in economic theory is that the individual or the firm is maximizing something, usually utility or profit. Economists, almost without exception, make constrained maximization the basic building block of any theory. Many of our empirical analyses seek to test models that are based on maximizing behavior. When we obtain results that seem to deviate from what would appear to be individually rational, we re-examine the evidence or revise the theory. But the theoretical revisions almost never drop the assumption that individuals are maximizing something, even if the something is unorthodox. Few economists are willing to concede that individuals simply do not know what they are doing. We may permit imperfect information, transaction costs, and other intervening variables to muddy the waters, but we do not model behavior as being determined by forces beyond the control of the individual. Most sociologists, by contrast, argue that understanding the constraints is more important than understanding the behavior that results from optimization, given the constraints.3 Edward P. Lazear Economic Imperialism July, 1999 See Jenkin (1931, originally 1871). 3 The emphasis on maximization is important because it allows an analyst to make predictions in new situations. When individuals are assumed to maximize something, a well-defined and predictable behavioral response to any stimulus can be derived. Other social sciences that are unwilling to assume maximization are in the position of being unable to predict in new situations. The maximum of a function is a well understood concept; other rules are not, especially when they vary from situation to situation. A corollary of maximization is that on the margin, there are always tradeoffs. The notion that there is no free lunch is central to economics. The simple, but crucial concept of opportunity cost lies behind much of the ability of economics to extend into other areas. Sometimes the tradeoffs are subtle. Prices and costs are not necessarily parameters that are observed in market data, but they affect behavior nonetheless. Other social sciences do not place the same weight on explicit recognition of the tension between costs and benefits, which reduces the ability of these fields to grapple systematically with social phenomena. Thinking about tradeoffs gives rise to related thoughts on substitutability. Economists place emphasis on choice. Things are not technologically determined. This is true for consumers and producers alike. There is no fixed number of jobs. Firms can trade off between employing labor and capital and workers can choose between labor and leisure. Second, as in the physical sciences, equilibrium is a central concept in economics. Virtually all economic theories have as primary desiderata that the behavior described must be consistent with some notion of equilibrium. Economic theory usually consists of modeling the behavior of agents. Then, behavior of the individual actors are aggregated to examine what happens when they interact. Often, this is in the context of a market. The economist’s most familiar tools are supply and demand, which appeared during the 19th century.4 Marshall (1890) made heavy use of these tools and derived a rich set implications and Edward P. Lazear Economic Imperialism July, 1999 Early examples include Hotelling (1938) and Bergson (1938). Formal analyses are found in Arrow (1951) and Debreu (1951). 4 testable predictions. Although the behavior of individuals who lie behind the supply and demand curves is inherently interesting, it is the interest in equilibrium itself that distinguishes economics from other social sciences. To be sure, other social sciences discuss spillover and feedback effects, but among social scientists, only economists insist on a physical-sciences-style equilibrium as part of the analysis. Third, much of economics is driven by the notion that efficiency is important. Adam Smith’s (1776) concept of the invisible hand is a guiding principle in economics. Individuals acting in their self-interest further the general goals of society. Smith took the moral ideas of the Enlightenment (especially the emphasis on free will) and transformed them into a positive theory of the economy, with limited or no role for the state. More formal statements have been provided during this century. The idea that competitive equilibrium is efficient appears in the literature since the time of Marshall.5 The importance of efficiency is not that it is an apology for the status quo. Efficiency is a concept that, together with equilibrium, pushes economists to do a particular kind of analysis. When economists model a situation and the resulting equilibrium is inefficient, usually there are trades that could have occurred that are implicitly or explicitly ruled out. The analyst or his critics are induced to ask what the reasons are and what market or other institutions could arise to remedy the situation. Thus, the focus on efficiency when combined with equilibrium prevents the economist from being content with partial answers and half-truths. The notion that efficiency is a natural outcome motivates a larger series of questions and initiates deeper analysis. It also permits economists to make clear, unambiguous policy statements, although the assumptions that lie behind welfare economics are somewhat controversial. Still, Pareto optimality is a well-defined concept that allows us to take an axiomatic approach to issues over which other fields can only wring their hands. Edward P. Lazear Economic Imperialism July, 1999 On rare occasion, sociologists develop models that discuss an equilibrium. One such example is Berger and Snell (1957). Interestingly, this paper was heavily influenced by economics, in particular, the work of Prais (1955a,b). An important more recent exception is sociobiology, e.g., Wilson (1975). This field uses the same approaches as those of economists to explain evolutionary developments. A nice summary of the literature on social selection of mates is found in Ridley (1993). This book makes constant reference to tradeoffs and to efficiency of equilibria and reads like an economics article. 5 Other social scientists generally ignore equilibrium considerations.6 In part, this is inten