曼昆經(jīng)濟(jì)學(xué)原理（第二版） principles of economics, 2nd edition

1、IN THIS CHAPTER YOU WILL . . .Discuss how incentives af fect people’s behaviorLearn the meaning of oppor tunity costLearn that economics is about the allocation of scarce resourcesExamine some of the tradeof fs that peop

2、le faceSee how to use marginal reasoning when making decisionsThe word economy comes from the Greek word for “one who manages a house- hold.” At first, this origin might seem peculiar. But, in fact, households and econom

3、ies have much in common. A household faces many decisions. It must decide which members of the household do which tasks and what each member gets in return: Who cooks din- ner? Who does the laundry? Who gets the extra de

4、ssert at dinner? Who gets to choose what TV show to watch? In short, the household must allocate its scarce re- sources among its various members, taking into account each member’s abilities, efforts, and desires. Like a

5、 household, a society faces many decisions. A society must decide what jobs will be done and who will do them. It needs some people to grow food, other people to make clothing, and still others to design computer softwar

6、e. Once soci- ety has allocated people (as well as land, buildings, and machines) to various jobs,T E N P R I N C I P L E SO F E C O N O M I C S3Consider why trade among people or nations can be good for everyoneDiscuss

7、 why markets are a good, but not per fect, way to allocate resourcesLearn what determines some trends in the overall economyCHAPTER 1 TEN PRINCIPLES OF ECONOMICS 5Or consider parents deciding how to spend their family in

8、come. They can buy food, clothing, or a family vacation. Or they can save some of the family income for retirement or the children’s college education. When they choose to spend an extra dollar on one of these goods, the

9、y have one less dollar to spend on some other good. When people are grouped into societies, they face different kinds of tradeoffs. The classic tradeoff is between “guns and butter.” The more we spend on national defense

10、 to protect our shores from foreign aggressors (guns), the less we can spend on consumer goods to raise our standard of living at home (butter). Also important in modern society is the tradeoff between a clean environmen

11、t and a high level of income. Laws that require firms to reduce pollution raise the cost of producing goods and services. Because of the higher costs, these firms end up earning smaller profits, paying lower wages, charg

12、ing higher prices, or some combination of these three. Thus, while pollution regulations give us the benefit of a cleaner environ- ment and the improved health that comes with it, they have the cost of reducing the incom

13、es of the firms’ owners, workers, and customers. Another tradeoff society faces is between efficiency and equity. Efficiency means that society is getting the most it can from its scarce resources. Equity means that the

14、benefits of those resources are distributed fairly among society’s members. In other words, efficiency refers to the size of the economic pie, and equity refers to how the pie is divided. Often, when government policies

15、are being designed, these two goals conflict. Consider, for instance, policies aimed at achieving a more equal distribution of economic well-being. Some of these policies, such as the welfare system or unem- ployment ins

16、urance, try to help those members of society who are most in need. Others, such as the individual income tax, ask the financially successful to con- tribute more than others to support the government. Although these poli

17、cies have the benefit of achieving greater equity, they have a cost in terms of reduced effi- ciency. When the government redistributes income from the rich to the poor, it re- duces the reward for working hard; as a res

18、ult, people work less and produce fewer goods and services. In other words, when the government tries to cut the economic pie into more equal slices, the pie gets smaller. Recognizing that people face tradeoffs does not

19、by itself tell us what decisions they will or should make. A student should not abandon the study of psychology just because doing so would increase the time available for the study of econom- ics. Society should not sto

20、p protecting the environment just because environmen- tal regulations reduce our material standard of living. The poor should not be ignored just because helping them distorts work incentives. Nonetheless, ac- knowledgin

21、g life’s tradeoffs is important because people are likely to make good decisions only if they understand the options that they have available.PRINCIPLE #2: THE COST OF SOMETHING IS WHAT YOU GIVE UP TO GET ITBecause peopl

22、e face tradeoffs, making decisions requires comparing the costs and benefits of alternative courses of action. In many cases, however, the cost of some action is not as obvious as it might first appear. Consider, for exa

23、mple, the decision whether to go to college. The benefit is in- tellectual enrichment and a lifetime of better job opportunities. But what is the cost? To answer this question, you might be tempted to add up the money yo