Автор: Пользователь скрыл имя, 21 Июня 2013 в 11:39, доклад
Economics has been recognized as a special area of study for over a century. Virtually all four-year colleges offer courses in economics and most allow students to major in the subject. Economists maintain high profiles in governments and they have been well-represented among the highest appointees in the federal government of the United States. The press reports on their doings and sayings, sometimes with praise and admiration, sometimes with ridicule and scorn. Economics and economists are words that almost everyone has heard of and uses. But what exactly is economics? Very few people can give a good definition or description of what this field of study is all about.
WELCOME TO ECONOMICS!
Economics has been recognized as a special area of study for over a century. Virtually all four-year colleges offer courses in economics and most allow students to major in the subject. Economists maintain high profiles in governments and they have been well-represented among the highest appointees in the federal government of the United States. The press reports on their doings and sayings, sometimes with praise and admiration, sometimes with ridicule and scorn. Economics and economists are words that almost everyone has heard of and uses. But what exactly is economics? Very few people can give a good definition or description of what this field of study is all about.
If ordinary citizens cannot give a good definition or description of economics, they can be excused because economists long struggled to define their field. In addition, the subject matter that economists study is not well-defined. In recent years, for example, economic journals have published papers on 'topics such as sex, crime, slavery, childbearing, and rats. It is not surprising, then, that one economist, in a lighter moment, suggested that economics can be defined as «what economists do».
Defining economics as «what economists do» does not tell us anything we did not already know. A good definition must explain what it is that makes economics a distinct subject, different from physics or psychology. One should not expect to find a short definition that conveys with absolute clarity all there is to know about economics (or else there would be no reason to spend hours learning about it). Neither should one believe that there is only one correct definition possible. Many good definitions are possible, and each will focus on some important aspect of the subject. To use an analogy, there is not one spot from which one can best view Niagara Falls. Each viewpoint obscures some features and emphasizes others. There are, of course, some spots that are clearly superior to others, but people can disagree about which is the very best spot.
One of the earliest and most famous definitions of economics was that of Thomas Carlyle, who in the early 19th century termed it the "dismal science." According to a much-repeated (but erroneous) story, what Carlyle had noticed was the anti-utopian implications of economics. Many Utopians, people who believe that a society of abundance without conflict is possible, believe that good results come from good motives and good motives lead to good results. Economists have always disputed this, and it was to the forceful statement of this disagreement by early economists such as Thomas Malthus and David Ricardo that Carlyle supposedly reacted.
Another early definition, one which is perhaps more useful, is that of English economist W. Stanley Jevons who, in the late 19th century, wrote that economics was "the mechanics of utility and self interest." One can think of economics as the social science that explores the results of people acting on the basis of self-interest. There is more to man than self-interest, and the other social sciences—such as psychology, sociology, anthropology, and political science-attempt to tell us about those other dimensions of man. As you read further into these pages, you will see that the assumption of self-interest, that a person tries to do the best for himself with what he has, underlies virtually all of economic theory At the turn of the century, Alfred Marshall's Principles of Economics was the most influential textbook in economics. Marshall defined economics as «a study of mankind in the ordinary business of life; it examines that part of individual and social action which is most closely connected with the attainment and with the use of the material requisites of wellbeing. Thus it is on one side a study of wealth; and on the other, and more important side, a part of the study of man».
Many other books of the period included in their definitions something about the "study of exchange and production." Definitions of this sort emphasize that the topics with which economics is most closely identified concern those processes involved in meeting man's material needs. Economists today do not use these definitions because the boundaries of economics have expanded since Marshall. Economists do more than study exchange and production, though exchange remains at the heart of economics.
Most contemporary definitions of economics involve the notions of choice and scarcity. Perhaps the earliest of these is by Lionell Robbins in 1935: "Economics is a science which studies human behavior as a relationship between ends and scarce means which have alternative uses." Virtually all textbooks have definitions that are derived from this definition. Though the exact wording differs from author to author, the standard definition is something like this: «Economics is the social science that examines how people choose to use limited or scarce resources in attempting to satisfy their unlimited wants».
Scarcity means that people want more than is available. Scarcity limits us both as individuals and as a society. As individuals, limited income (and time and ability) keep us from doing and having all that we might like. As a society, limited resources (such as manpower, machinery, and natural resources) fix a maximum on the amount of goods and services that can be produced.
Scarcity requires choice. People must choose which of their desires they will satisfy and which they will leave unsatisfied. When we, either as individuals or as a society, choose more of something, scarcity forces us to take less of something else. Economics is sometimes called the study of scarcity because economic activity would not exist if scarcity did not force people to make choices.
When there is scarcity and choice, there are costs. The cost of any choice is the option or options that a person gives up. For example, if you gave up the option of playing a computer game to read this text, the cost of reading this text is the enjoyment you would have received playing the game. Most of economics is based on the simple idea that people make choices by comparing the benefits of option A with the benefits of option B (and all other options that are available) and choosing the one with the highest benefit. Alternatively, one can view the cost of choosing option A as the sacrifice involved in rejecting option B, and then say that one chooses option A when the benefits of A outweigh the costs of choosing A (which are the benefits one loses when one rejects option B).
The widespread use of definitions emphasizing choice and scarcity shows that economists believe that these definitions focus on a central and basic part of the subject. This emphasis on choice represents a relatively recent insight into what economics is all about; the notion of choice is not stressed in older definitions of economics. Sometimes, this insight yields rather clever definitions, as in James Buchanan's observation that an economist is one who disagrees with the statement that whatever is worth doing is worth doing well. What Buchanan is noting is that time is scarce because it is limited and there are many things one can do with one's time. If one wants to do all things well, one must devote considerable time to each, and thus must sacrifice other things one could do. Sometimes, it is wise to choose to do some things poorly so that one has more time for other things.