《货币与信用理论》学习指南第二编第十一章

第二编 货币的价值

第十一章 货币客观交换价值及其变化的度量问题

章节大纲

一、问题的历史

Some of the greatest minds in economics have devoted themselves to the development of indexes that would provide an objective measurement of the change in the purchasing power of money. However, such statistical techniques have never lived up to their promises, as even their own creators often admitted.
经济学领域中一些最伟大的思想家致力于指数的发明，这些指数将为货币购买力的变化提供客观的衡量标准。然而，像指数的发明者们经常承认的那样，这些统计技术从未实现他们的承诺。

二、问题的本质

Just as we can express the price of any commodity by reference to how many units of money it takes to purchase one unit of the commodity, the opposite approach can yield the “price” of a unit of money in terms of the commodity. However, this technique yields as many “prices” of money as there are commodities. What economists desire is a method for combining all of this information into a single measurement of “the” purchasing power of money. Then, a second task is to ask of any particular commodity’s price change, how much can be attributed to forces arising from the side of money (in contrast to a change in the relative scarcity of the good which would also make its price rise).
正如我们可以通过参考购买一单位商品所需的货币数量来表达任何商品的价格一样，相反的方式可以产生单位货币的“商品价格”。然而，这种方式产生的货币“价格”和商品种类一样多。经济学家所希望获得的是一种方法，能够将所有这些信息结合到单一尺度的“唯一”货币购买力中。然后，第二个任务，是为任何特定商品的价格变化有多少可以归因于货币方面的力量来提供证据（相比之下，商品相对稀缺性的变化也会使其价格上涨）。

三、计算指数的方法

Nearly all attempts at measuring the objective exchange value of money have relied on the assumption that if a large enough collection of goods are included in the “basket” to be measured, then changes in the relative scarcities of the goods themselves will largely cancel out. Thus the average or net change in the prices of all the goods (as quoted in money) will demonstrate whether the purchasing power of money has risen or fallen. Unfortunately, in practice it is only possible to carry out such calculations by making ad hoc assumptions about the relative importance of various factors. In the end, the economic theorist does not gain much from studying the various statistics of price movements that he could not obtain from deductive reasoning about the nature of exchange and money.
几乎所有衡量货币客观交换价值的尝试都是基于这样一个假设：如果要测量的“篮子”中包含了足够多的商品集合，那么商品本身相对稀缺性的变化将在很大程度上互相抵消。因此，所有商品价格（以货币报价）的平均或净变化将证实货币购买力是上升还是下降。不幸的是，在实践中，只有通过对各种因素的相对重要性作出特别假设，才能进行这种计算。最后，经济理论家从关于交换和货币性质的演绎推理中无法获得的东西，他从研究价格变动的各种统计数据中同样无法获得。

四、维塞尔关于指数计算方法的改进

Wieser devised the most careful and satisfactory approach to measuring the objective exchange value of money, with a technique involving the contrast between nominal and real income. However, even Wieser’s approach had several fatal flaws. For example, over large stretches of time, the types of income people could earn become incommensurable, robbing Wieser’s technique of its desired precision.
维塞尔设计了一种最为谨慎和令人满意的方法来衡量货币的客观交换价值，这种方法涉及到名义收入和实际收入之间的对比。然而，即使是维塞尔的方法也有几个致命的缺陷。例如，长期来看，人们可以获得的收入类型变得不可通约，剥夺了维塞尔方法所要求的精确性。

五、指数的实际用途

The criticisms leveled against various techniques for calculating index numbers refer to the problems of economic theory. In practical use for government policy, these techniques provide a rough guide to changes in the purchasing power of money.
针对各种指数计算方法的批评同样适用于经济理论问题。在政府政策的实际运用中，这些方法为货币购买力的变化提供了粗略的指导。

技术说明

• On page 189 Mises writes, “Invariability in respect of the property to be measured . . . is a sine qua non of all measurement.” For example, if a person is using a meter stick to measure length, then he must be assuming that the meter stick’s length is itself invariable. Yet when economists try to measure changes in the objective exchange value of money (i.e., in the purchasing power of money), they run into the problem that there are no such invariable benchmarks. If the exchange ratio between money and any other commodity changes, it is not clear whether the change originates from the side of money or the commodity.

• 在英文版第189页，米塞斯写道：“相对于被度量财产的不变性…是所有度量的必要条件。”例如，如果一个人使用米尺来测量长度，那么他必须假设米尺本身的长度是不变的。然而，当经济学家试图衡量货币的客观交换价值（即货币购买力）的变化时，他们遇到了这样一个问题：没有这样不变的基准。如果货币与任何其它商品之间的交换比率发生了变化，这种变化是来源于货币还是商品是不清楚的。

• Some numerical examples may clarify Mises’s observations on index numbers (pp. 188–90). If the price of oil increases from 100, while the price of a television falls from 90, it is possible that these changes have nothing to do with the purchasing power of money, and merely reflect a shift in demand away from televisions and into oil. On the other hand, if all prices (quoted in money) in the community increased exactly by 10 percent in one year, then it would be clear that the purchasing power of money had fallen and was the driver of the price increases. But in the real world, things are never so clear-cut. Typically some prices rise while others fall, and the price movements are not in the same percentages across commodities. There is no nonarbitrary way to determine how much of a given good’s change in price is due to changes in its relative value (with respect to other commodities) versus a change in the purchasing power of money.
  一些数值案例可以阐明米塞斯对指数的观察（英文版第188-190页）。如果石油价格从90美元上涨到100美元，而电视价格从100美元下降到90美元，这些变化可能与货币购买力无关，仅仅反映了需求从电视转向石油。另一方面，如果社区所有价格（以货币报价）在一年内精确上涨10%，那么很明显货币购买力下降，而且这是价格上涨的驱动因素。但在现实世界中，事情从来没有这么明晰过。通常情况下，有些价格上涨，而另一些价格下跌，而且不同商品之间价格变动的百分比不相同。没有一种非任意的方法来确定一种给定商品的价格变化有多少是由于其相对价值（相对于其他商品）的变化，有多少是由于货币购买力的变化。

研究问题

1. Explain: “Only by letting fall morsels of statistics is it possible for the economic theorist to maintain his prestige in the face of questions of this sort.” (p. 188)

2. 解释：“经济理论家在面对这类问题时，只有提出一些统计数据，才能维护其声誉。”（英文版第188页）

3. Explain:“He who cares to go to the trouble of demonstrating the uselessness of index numbers for monetary theory and the concrete tasks of monetary policy will be able to select a good proportion of his weapons from the writings of the very men who invented them.” (p. 188)

4. 解释：“那些不辞辛苦想证明指数对于货币理论和货币政策的具体任务没有任何作用的人们，可以从指数发明者的著作中选择他们可用的大部分武器。”（英文版第188页）

5. Why are index numbers not very important for the “extension of the theory of the nature and value of money”? (pp. 189–90)

6. 为什么指数对于“货币性质和价值的理论的扩展”不是很重要？（英文版189-190页）

7. Even if we grant for the sake of argument that a loaf of bread possesses a constant utility in the objective sense of food value, why is this approach unhelpful when it comes to the use of index numbers in monetary theory? (p. 193)

8. 即使我们为了论证而假设在客观意义上，一条面包总是具有相同的效用，永远具有相同的食物价值，为什么这种方法对于指数在货币理论中的应用没有帮助？（英文版第193页）

9. Does Mises think that index numbers are completely useless? (p. 194)

10. 米塞斯认为指数是完全无用的吗？（英文版第194页）