Critical Reasoning

The economy around Lake Paqua depends on fishing of the lake's landlocked salmon population. In recent years, scarcity of food for salmon there has caused a decline in both the number and the size of the adult salmon in the lake. As a result, the region's revenues from salmon fishing have declined significantly. To remedy this situation, officials plan to introduce shrimp, which can serve as a food source for adult salmon, into Lake Paqua. Which of the following, if true, most seriously calls into question the plan's chances for success?

Researchers asked volunteers to imagine they were running a five-kilometer race against 50 people and then against 500 people, races in each of which the top 10 percent would receive a $1,000 prize. Asked about the effort they would apply in the respective cases, the volunteers indicated, on average, that they would run slower in the race against the greater number of people. A likely explanation of this result is that those of the volunteers who were most comparatively inclined�those who most tended to compare themselves with others in the social environment�determined (perhaps unconsciously) that extreme effort would not be worthwhile in the 500-competitor race. Which of the following would, if known to be true, most help justify the explanation offered above?

Linguist: In English, the past is described as �behind� and the future �ahead,� whereas in Aymara the past is �ahead� and the future �behind.� Research indicates that English speakers sway backward when discussing the past and forward when discussing the future. Conversely, Aymara speakers gesture forward with their hands when discussing the past and backward when discussing the future. These bodily movements, therefore, suggest that the language one speaks affects how one mentally visualizes time. The linguist's reasoning depends on assuming which of the following?

In the country of Marut, the Foreign Trade agency's records were reviewed in 1994 in light of information then newly available about neighboring Goro. The review revealed that in every year since 1963, the agency's projection of what Goro's gross national product (GNP) would be five years later was a serious underestimate. The review also revealed that in every year since 1963, the agency estimated Goro's GNP for the previous year�a Goro state secret�very accurately. Of the following claims, which is most strongly supported by the statements given ?

A product that represents a clear technological advance over competing products can generally command a high price. Because technological advances tend to be quickly surpassed and companies want to make large profits while they still can, many companies charge the maximum possible price for such a product. But large profits on the new product will give competitors a strong incentive to quickly match the new product's capabilities. Consequently, the strategy to maximize overall profit from a new product is to charge less than the greatest possible price. B The first is a consideration raised to explain the appeal of a certain strategy; the second is a consideration raised to call into question the wisdom of adopting that strategy. C The first is an assumption that has been used to justify a certain strategy; the second is a consideration that is used to cast doubt on that assumption. D The first is a consideration raised in support of a strategy the argument endorses; the second presents grounds in support of that consideration. E The first is a consideration raised to show that adopting a certain strategy is unlikely to achieve the intended effect; the second is presented to explain the appeal of that strategy.

Last year a record number of new manufacturing jobs were created. Will this year bring another record? Well, any new manufacturing job is created either within an existing company or by the start-up of a new company. Within existing firms, new jobs have been created this year at well below last year's record pace. At the same time, there is considerable evidence that the number of new companies starting up will be no higher this year than it was last year and there is no reason to think that the new companies starting up this year will create more jobs per company than did last year's start-ups. So clearly, the number of new jobs created this year will fall short of last year's record. In the argument given, the two portions in boldface play which of the following roles?

Paleontologist: About 2.8 million years ago, many species that lived near the ocean floor suffered substantial population declines. These declines coincided with the onset of an ice age. The notion that cold killed those bottom-dwelling creatures outright is misguided, however; temperatures near the ocean floor would have changed very little. Nevertheless, the cold probably did cause the population declines, though indirectly. Many bottom-dwellers depended for food on plankton, small organisms that lived close to the surface and sank to the bottom when they died. Most probably, the plankton suffered a severe population decline as a result of sharply lower temperatures at the surface, depriving many bottom-dwellers of food. In the paleontologist's reasoning, the two portions in boldface play which of the following roles?

Airline Representative: The percentage of flight delays caused by airline error decreased significantly this year. This indicates that airlines listened to complaints about preventable errors and addressed the problems. Although delays caused by weather and other uncontrollable factors will always be part of travel, preventable delays are clearly decreasing. Which of the following most clearly points to a logical flaw in the representative's reasoning?

Lockeport's commercial fishing boats use gill nets, which kill many of the netted fish, including some fish of endangered species. The fishing commission has proposed requiring the use of tent nets, which do not kill fish; boat crews would then throw back fish of endangered species. Profitable commercial fishing boats in similar areas have already switched over to tent nets. The proposal can therefore be implemented without economic harm to Lockeport's commercial fishing boat operators. Which of the following, if true, casts the most serious doubt on the argument made for the proposal?

Educational Theorist: Recent editorials have called for limits on the amount of homework assigned to schoolchildren younger than 12. They point out that free-time activities play an important role in childhood development and that homework in large quantities can severely restrict children's free time, hindering their development. But the actual average homework time for children under 12�little more than 30 minutes per night�leaves plenty of free time. In reality, therefore, the editorials' rationale cannot justify the restriction they advocate. Which of the following, if true, would most seriously call into question the educational theorist's conclusion?

Political Strategist: The domestic policies of our opponents in Party X are contrary to the priorities of many middle-class voters. Yet some of these same voters are supporters of Party X and its candidates due to the party's appeals about foreign policy. In order to win these voters back, we in Party Y must prove to middle-class voters that Party X does not represent their priorities with respect to domestic policy. Which of the following would, if true, most strongly suggest that the political strategist's plan is unlikely to succeed?

A product that represents a clear technological advance over competing products can generally command a high price. Because technological advances tend to be quickly surpassed and companies want to make large profits while they still can, many companies charge the maximum possible price for such a product. But large profits on the new product will give competitors a strong incentive to quickly match the new product's capabilities. Consequently, the strategy to maximize overall profit from a new product is to charge less than the greatest possible price. B The first is a consideration raised to support the strategy that the argument recommends; the second presents that strategy. C The first is a consideration raised to help explain the popularity of a certain strategy; the second presents that strategy. D The first is an assumption, rejected by the argument, that has been used to justify a course of action; the second presents that course of action. E The first is a consideration that has been used to justify adopting a certain strategy; the second presents the intended outcome of that strategy.

Theater Critic: The play La Finestrina, now at Central Theater, was written in Italy in the eighteenth century. The director claims that this production is as similar to the original production as is possible in a modern theater. Although the actor who plays Harlequin the clown gives a performance very reminiscent of the twentieth-century American comedian Groucho Marx, Marx�s comic style was very much within the comic acting tradition that had begun in sixteenth-century Italy. The considerations given best serve as part of an argument that

In countries where automobile insurance includes compensation for whiplash injuries sustained in automobile accidents, reports of having suffered such injuries are twice as frequent as they are in countries where whiplash is not covered. Presently; no objective test for whiplash exists, so it is true that spurious reports of whiplash injuries cannot be readily identified. Nevertheless, these facts do not warrant the conclusion drawn by some commentators that in the countries with the higher rates of reported whiplash injuries, half of the reported cases are spurious. Clearly, in countries where automobile insurance does not include compensation for whiplash, people often have little incentive to report whiplash injuries that they actually have suffered. In the argument given, the two boldfaced portions play which of the following roles?

Since it has become known that several of a bank's top executives have been buying shares in their own bank, the bank's depositors, who had been worried by rumors that the bank faced impending financial collapse, have been greatly relieved. They reason that, since top executives evidently have faith in the bank's financial soundness, those worrisome rumors must be false. Such reasoning might well be overoptimistic, however, since corporate executives have been known to buy shares in their own company in a calculated attempt to dispel negative rumors about the company's health. In the argument given, the two boldfaced portions play which of the following roles?

Which of the following most logically completes the passage? According to the last pre-election poll in Whippleton, most voters believe that the three problems government needs to address, in order of importance, are pollution, crime, and unemployment. Yet in the election, candidates from parties perceived as strongly against pollution were defeated, while those elected were all from parties with a history of opposing legislation designed to reduce pollution. These results should not be taken to indicate that the poll was inaccurate, however, since __________.

Mansour: We should both plan to change some of our investments from coal companies to less polluting energy companies. And here's why. Consumers are increasingly demanding nonpolluting energy, and energy companies are increasingly supplying it. Therese: I'm not sure we should do what you suggest. As demand for nonpolluting energy increases relative to supply, its price will increase, and then the more polluting energy will cost relatively less. Demand for the cheaper, dirtier energy forms will then increase, as will the stock values of the companies that produce them. Therese responds to Mansour's proposal by doing which of the following?

Sammy: For my arthritis, I am going to try my aunt's diet: large amounts of wheat germ and garlic. She was able to move more easily right after she started that diet. Pat: When my brother began that diet, his arthritis got worse. But he has been doing much better since he stopped eating vegetables in the nightshade family, such as tomatoes and peppers. Which of the following, if true, would provide a basis for explaining the fact that Sammy's aunt and Pat's brother had contrasting experiences with the same diet?

Fast-food restaurants make up 45 percent of all restaurants in Cantaria. Customers at these restaurants tend to be young; in fact, studies have shown that the older people get, the less likely they are to eat in fast-food restaurants. Since the average age of the Canatrian population is gradually rising and will continue to do so, the number of fast-food restaurants is likely to decrease. Which of the following, if true, most seriously weakens the argument?

Voters commonly condemn politicians for being insincere, but politicians often must disguise their true feelings when they make public statements. If they expressed their honest views�about, say, their party's policies�then achieving politically necessary compromises would be much more difficult. Clearly, the very insincerity that people decry shows that our government is functioning well. Which of the following, if true, most seriously undermines this reasoning?