「Question No. 31」

　　The brief passage:

　　The following appeared in a memorandum from the planning department of an electric power company.

　　“Several recent surveys indicate that home owners are increasingly eager to conserve energy. At the same time, manufacturers are now marketing many home appliances, such as refrigerators and air conditioners, that are almost twice as energy efficient as those sold a decade ago. Also, new technologies for better home insulation and passive solar heating are readily available to reduce the energy needed for home heating. Therefore, the total demand for electricity in our area will not increase — and may decline slightly. Since our three electric generating plants in operation for the past twenty years have always met our needs, construction of new generating plants will not be necessary.”

　　The instruction:

　　Write a response in which you examine the stated and/or unstatedassumptions of the argument. Be sure to explain how the argument depends on these assumptions and what the implications are for the argument if the assumptions prove unwarranted.

　　Introduction

　　指出brief passage里的conclusion是什么 → According to the argument, construction of new electricity generating plants will not be necessary for the area. 依据指令的套话 → However, during the line of reasoning, there are multipleuntenable assumptions, and, as a result, the conclusion, based on those assumptions, is vulnerable / unsound.

　　Body

　　题目推理过程中出现的逻辑类型(以其中3个逻辑点示范写作)：

　　研究方法 → 首先，提出assumption是什么 → The author assumes that the results of the surveys are admissible. This is a questionable assumption, however. 解释assumption的漏洞 → In fact, the results may be invalid, because the surveys may be poorly designed, and, as a result, information collected is likely tomisrepresent home owners’ ideas, or home owners may give answers that are not what they truly think.

　　时间 →与上一点讨论形成关联 → Even if the surveys and their results are perfectly valid, 讨论逻辑漏洞的具体内容 → the results may indicate the trend or householders’ ideas that are only recent, because the surveys are recently conducted. If the surveys will be conducted again in some time, they may find home owners’ ideas that are different from the recent ideas. 以结论的方式提出assumption是什么 → Therefore, the author cannot assume that the recent surveys indicate a usual situation.

　　偷换概念 → 略

　　多个变量(份数每份数)之1 →首先，提出assumption是什么→ It is arefutable assumption that a more energy-efficient model of an appliance consumes less energy in total than does the old model. 解释assumption的漏洞 → If the time of use of an energy-efficient appliance is increased by its user, the total energy consumption may be greater than that of a less energy-efficient model. In this case, a household’s energy consumption or demand may not decrease, despite the use of appliances that are more energy-efficient.

　　多个变量(份数每份数)之2 → 首先，提出assumption是什么 → The author also assumes that the area’s number of households will not change. 解释assumption的漏洞 → As a matter of fact, the number of households may increase. For example, there may be immigrants moving to the area, or adult children moving out of their parents’ homes and live independently in the same area. As a result of this increase, the area’s total demand for electricity may grow, a situation contradicting the author’s prediction.

　　多个变量(加减法) → 略

　　Conclusion

　　“补偿性的”说明 → If the author could provide additional information, there would not be so many assumptions that are refuted above. As a result, it would be a logically sound conclusion that the area will not need to construct new power plants.