29 The Advantage of International Trade

课时教学实施方案I.Definitions:1. cost: The total money, time and resources associated with a purchase or activity.2. absolute advantage: The name for the ability of one entity to engage in more efficient production than another entity. Assuming equal inputs, the entity with an absolute advantage will have a greater output.3. comparative advantage: The name for the ability of one business entity to engage in production at a lower opportunity cost than another entity. Comparative advantage, rather than absolute advantage, is useful in determining what should be produced and what should be acquired through trade.大卫·李嘉图在其代表作《政治经济学及赋税原理》中提出了比较成本贸易理论（后人称为“比较优势贸易理论”）。

比较优势理论认为，国际贸易的基础是生产技术的相对差别（而非绝对差别），以及由此产生的相对成本的差别。

每个国家都应根据“两利相权取其重，两弊相权取其轻”的原则，集中生产并出口其具有“比较优势”的产品，进口其具有“比较劣势”的产品。

比较优势贸易理论在更普遍的基础上解释了贸易产生的基础和贸易利得，大大发展了绝对优势贸易理论。

一国在两种商品生产上较之另一国均处于绝对劣势，但只要处于劣势的国家在两种商品生产上劣势的程度不同，处于优势的国家在两种商品生产上优势的程度不同，则处于劣势的国家在劣势较轻的商品生产方面具有比较优势，处于优势的国家则在优势较大的商品生产方面具有比较优势。

两个国家分工专业化生产和出口其具有比较优势的商品，则两国都能从贸易中得到利益。

4.opportunity cost: The cost of passing up the next best choice when making a decision. For example, if an asset such as capital is used for one purpose, the opportunity cost is the value of the next best purpose the asset could have been used for. Opportunity cost analysis is an important part of a company's decision-making processes, but is not treated as an actual cost in any financial statement. 机会成本指当人面临抉择时，他必须作出一定的选择，他所失去的就是他所得到的东西的机会成本。

对商业公司来说，用一定的时间或资源生产一种商品时，失去的利用这些资源生产其他最佳替代品的机会就是机会成本。

在生活中，有些机会成本是可以用货币来进行衡量的。

例如，农民在获得更多土地时，如果选择养猪就不能选择养鸡，养猪的机会成本就是放弃养鸡的收益。

但有些机会成本往往无法用货币衡量，例如，在图书馆看书学习还是享受电视剧带来的快乐之间进行选择。

II. Adam Smith and his brief introduction亚当.斯密（Adam Smith，1723～1790），是英国古典政治经济学的主要代表人物之一。

他的代表作《国富论》（全称《国民财富的性质和原因的研究》）早已被翻译成十几种文字，全球发行。

而他本人也因此被奉为现代西方经济学的鼻祖。

1767年，他返回家乡克科第埋首于《国富论》的写作。

1776年，凝聚了亚当.斯密十年心血的《国富论》终于问世。

此书一出，极受英国资产阶级的欢迎与褒誉，因为它为实行自由放任的经济政策提供了理论根据。

亚当.斯密成了最受欢迎的经济学家，《国富论》的观点成了国会议员的常用论据，甚至连当时的英国首相皮特也自称是斯密的学生。

不知不觉间，斯密来到了他一生中最风光得意的时刻。

1778年，他出任爱丁堡的海关专员，1787年一度出任格拉斯哥大学的校长，但在经济理论再也没有什么新成就。

这究竟是因为他已经来到他所出于的时代所能达到的极限，还是因为"生于忧患，死于安乐"--满足于现状而缺乏进取，就有待后人思考。

无论如何，无可否认的是，《国富论》的确是一部划时代的巨著。

它概括了古典政治经济学在形成阶段的理论成就，它最早系统地阐述了政治经济学的各个主要学说，它标志着自由资本主义时代的到来。

Adam Smith was born in Kirkcaldy, Fife, Scotland. The exact date of his birth is unknown, however, he was baptized on June 5, 1723. Smith was the Scottish political economist and philosopher, who became famous for his influential book "The Wealth of Nations" written in 1776.In 1751 Smith was appointed professor of logic at Glasgow University, transferring in 1752 to the chair of moral philosophy. His lectures covered the field of ethics, rhetoric, jurisprudence and political economy, or "police and revenue." In 1759 he published his Theory of Moral Sentiments, embodying some of his Glasgow lectures. This work was about those standards of ethical conduct that hold society together, with emphasis on the general harmony of human motives and activities under a beneficent Providence.Smith moved to London in 1776, where he published An Inquiry into the Nature and Causes of the Wealth of Nations, which examined in detail the consequences of economic freedom. It covered such concepts as the role of self-interest, the division of labor, the function of markets, and the international implications of a laissez-faire economy. "Wealth of Nations" established economics as an autonomous subject and launched the economic doctrine of free enterprise.Smith laid the intellectual framework that explained the free market and still holds true today. He is most often recognized for the expression "the invisible hand," which he used to demonstrate how self-interest guides the most efficient use of resources in a nation's economy, with public welfare coming as a by-product. To underscore his laissez-faire convictions, Smith argued that state and personal efforts, to promote social good are ineffectual compared to unbridled market forces.In 1778 he was appointed to a post of commissioner of customs in Edinburgh, Scotland. He died there on July 17, 1790, after an illness. At the end it was discovered that Smith had devoted a considerable part of his income to numerous secret acts of charity.III. David Ricardo and his introductionWhat did David Ricardo mean when he coined the term comparative advantage? According to the principle of comparative advantage, the gains from trade follow from allowing an economy to specialise. If a country is relatively better at making wine than wool, it makes sense to put more resources into wine, and to export some of the wine to pay for imports of wool. This is even true if that country is the world's best wool producer, since the country will have more of both wool and wine than it would have without trade. A country does not have to be best at anything to gain from trade. The gains follow from specializing in those activities which, at world prices, the country is relatively better at, even though it may not have an absolute advantage in them. Because it is relative advantage that matters, it is meaningless to say a country has a comparative advantage in nothing. The term is one of the most misunderdstood ideas in economics, and is often wrongly assumed to mean an absolute advantage compared with other countries.David Ricardo (1772-1823)David Ricardo was one of those rare people who achieved tremendous success and lasting fame. After his family disinherited him for marrying outside his Jewish faith, Ricardo made a fortune as a stockbroker and a loan broker. When he died, his estate was worth over $100 million in today's dollars. At age twenty-seven, after reading Adam Smith's The Wealth of Nations, Ricardo got excited about economics. He wrote his first economics article at age thirty-seven and then spent only fourteen years—his last ones—as a professional economist.Ricardo first gained notice among economists over the "bullion controversy." In 1809 he wrote that England's inflation was the result of the Bank of England's propensity to issue excess bank notes. In short, Ricardo was an early believer in the quantity theory of money, or what is known today as monetarism.In his Essay on the Influence of a Low Price of Corn on the Profits of Stock (1815), Ricardo articulated what came to be known as the law of diminishing returns. One of the most famous laws of economics, it holds that as more and more resources are combined in production with a fixed resource—for example, as more labor and machinery are used on a fixed amount of land—the additions to output will diminish.Ricardo also opposed the protectionist Corn Laws, which restricted imports of wheat. In arguing for free trade, Ricardo formulated the idea of comparative costs, today called comparative advantage. Comparative advantage—a very subtle idea—is the main basis for most economists' belief in free trade today. The idea is this: a country that trades for products that it can get at lower cost from another country is better off than if it had made the products at home.Say, for example, that Poorland can produce one bottle of wine with five hours of labor and one loaf of bread with ten hours. Richland's workers, on the other hand, are more productive. They produce a bottle of wine with three hours of labor and a loaf of bread with one hour. One might think at first that because Richland requires fewer labor hours to produce either good, it has nothing to gain from trade.Think again. Poorland's cost of producing wine, although higher than Richland's in terms of hours of labor, is lower in terms of bread. For every bottle produced, Poorland gives up half of a loaf, while Richland has to give up three loaves to make a bottle of wine. Therefore, Poorland has a comparative advantage in producing wine. Similarly, for every loaf of bread it produces, Poorland gives up two bottles of wine, but Richland gives up only a third of a bottle. Therefore, Richland has a comparative advantage in producing bread.If they exchange wine and bread one-for-one, Poorland can specialize in producing wine and trading some of it to Richland, and Richland can specialize in producing bread. Both Richland and Poorland will be better off than if they hadn't traded. By shifting, say, ten hours of labor out of producing bread, Poorland gives up the one loaf that this labor could have produced. But thereallocated labor produces two bottles of wine, which will trade for two loaves of bread. Result: trade nets Poorland one additional loaf of bread. Nor does Poorland's gain come at Richland's expense. Richland gains also, or else it would not have traded. By shifting three hours out of producing wine, Richland cuts wine production by one bottle but increases bread production by three loaves. It trades two of these loaves for Poorland's two bottles of wine. Richland has one more bottle of wine than it had before, and an extra loaf of bread.These gains come, Ricardo observed, because each country specializes in producing the good for which its comparative cost is lower.Writing a century before Paul Samuelson and other modern economists popularized the use of equations, Ricardo is still esteemed for his uncanny ability to arrive at complex conclusions without any of the mathematical tools now deemed essential. As economist David Friedman put it in his 1990 textbook, Price Theory, "The modern economist reading Ricardo's Principles feels rather as a member of one of the Mount Everest expeditions would feel if, arriving at the top of the mountain, he encountered a hiker clad in T-shirt and tennis shoes."One of Ricardo's chief contributions, arrived at without mathematical tools, is his theory of rents. Borrowing from Malthus, with whom Ricardo was closely, but often diametrically, associated, Ricardo explained that as more land was cultivated, farmers would have to start using less productive land. But because a bushel of corn from less productive land sells for the same price as a bushel from highly productive land, tenant farmers would be willing to pay more to rent the highly productive land. Result: the landowners, not the tenant farmers, are the ones who gain from productive land. This finding has withstood the test of time. Economists use Ricardian reasoning today to explain why agricultural price supports do not help farmers per se but do make owners of farmland wealthier. Economists use similar reasoning to explain why the beneficiaries of laws that restrict the number of taxicabs are not cab drivers per se but rather those who owned the limited number of taxi medallions (licenses) when the restriction was first imposed.IV. Important words to know: financial, advantage, benefit, specialization, output, Law of Comparative Costs, comparative advantage, classical economists, absolute advantage, absolute disadvantageV. Other words to grasp: make a profit, be capable of doing, proficient, specialize in, reveal, efficient, maximize。