During the late seventies when Japan was rapidly expanding its share of the

　　American auto¹ market， GM surveyed owners of GM cars and asked them whether t

　　hey would be more willing to buy a large， powerful car or a small， economica

　　l car. Seventy percent of those who responded said that they would prefer a

　　large car. On the basis of this survey， GM decided² to continue building larg

　　e cars. Yet during the'80s， GM lost even more of the market to the Japanese

　　……

　　Which one of the following， if it were determined³ to be true， would best exp

　　lain this discrepancy⁴.

　　（A） Only 10 percent of those who were polled replied.

　　（B） Ford⁵ which conducted a similar survey with similar results continued to

　　build large cars and also lost more of their market to the Japanese.

　　（C） The surveyed owners who preferred big cars also preferred big homes.

　　（D） GM determined that it would be more profitable to make big cars.

　　（E） Eighty percent of the owners who wanted big cars and only 40 percent of

　　the owners who wanted small cars replied to the survey.

　　The argument generalizes from the survey to the general car-buying populatio

　　n， so the reliability⁶ of the projection⁷ depends on how representative the sa

　　mple is. At first glance， choice （A） seems rather good， because 10 percent d

　　oes not seem large enough. However， political opinion polls are typically ba

　　sed on only .001 percent of the population. More importantly， we don't know

　　what percentage of GM car owners received the survey. Choice （B） simply stat

　　es that Ford made the same mistake that GM did. Choice （C） is irrelevant⁸. Ch

　　oice （D）， rather than explaining the discrepancy， gives even more reason for

　　GM to continue making large cars. Finally， choice （E） points out that part

　　of the survey did not represent the entire public， so （E） is the answer.

　　Analogy

　　To argue by analogy is to claim that because two things are similar in some

　　respects， they will be similar in others. Medical experimentation⁹ on animals

　　is predicated on such reasoning. The argument goes like this： the metabolis

　　m of pigs， for example， is similar to that of humans， and high doses of sacc

　　harine cause cancer in pigs. Therefore， high doses of saccharine¹⁰ probably ca

　　use cancer in humans

Clearly， the greater the similarity between the two things being compared th

　　e stronger the argument will be. Also the less ambitious the conclusion the

　　stronger the argument will be. The argument above would be strengthened by c

　　hanging “probably” to “may.” It can be weakened by pointing out the dissimil

　　arities between pigs and people.

　　Example：

　　Just as the fishing line becomes too taut¹¹， so too the trials and tribulation¹²

　　s of life in the city can become so stressful that one's mind can snap.

　　Which one of the following most closely parallels the reasoning used in the

　　argument above？

　　（A） Just as the bow may be drawn¹³ too taut， so too may one's life be wasted p

　　ursuing self-gratification.

　　（B） Just as a gambler's fortunes change unpredictably， so too do one's caree

　　r opportunities come unexpectedly.

　　（C） Just as a plant can be killed by over watering it， so too can drinking t

　　oo much water lead to lethargy.

　　（D） Just as the engine may race too quickly， so too may life in the fast lan

　　e lead to an early death.

　　（E） Just as an actor may become stressed before a performance， so too may dw

　　elling on the negative cause depression.

　　The argument compares the tautness¹⁴ in a fishing line to the stress of city l

　　ife； it then concludes that the mind can snap just as the fishing line can.

　　So we are looking for an answer-choice that compares two things and draws a

　　conclusion based on their similarity. Notice that we are looking for an argu

　　ment that uses similar reasoning， but not necessarily similar concepts. In f

　　act， an answer-choice that mentions either tautness or stress will probably

　　be a same-language trap.

　　Choice （A） uses the same-language trap——notice “too taut.” The analogy betwe

　　en a taut bow and self-gratification is weak， if existent. Choice （B） offers

　　a good analogy but no conclusion. Choice （C） offers both a good analogy and

　　a conclusion； however， the conclusion， “leads to lethargy，” understates the

　　scope of what the analogy implies. Choice （D） offers a strong analogy and a

　　conclusion with the same scope found in the original： “the engine blows， th

　　e person dies“； ”the line snaps， the mind snaps.“ This is probably the best

　　answer， but still we should check every choice. The last choice， （E）， uses l

　　anguage from the original， “stressful，” to make its weak analogy more tempti

　　ng. The best answer， therefore， is （D）。

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