五、逻辑问题例文分析
Case Study 3
The following appeared in the editorial section of a newspaper.
As public concern over drug abuse has increased, authorities have become more vigilant in their effort to prevent illegal drugs from entering the country. Many drug traffickers have consequently switched from marijuana, which is bulky, or heroin, which has a market too small to justify the risk of severe punishment, to cocaine. Thus enforcement efforts have ironically resulted in an observed increase in the illegal use of cocaine.
Student Essay
The argument that enforcement effort over illegal drag trade, incurred by the increase of public concern over drug abuse, resulted in an observed increase in the illegal use of cocaine sound reasonable at first. But the fact that movement against drag abuse is the venture of all human being and all the responsibility of all governments, and other reasons below will weak the result, or draw to an opposite conclusion.
Drug abuse brings us human being nothing but a disaster, mental aberration, debilitated health, career desolation, family breakage and peoples totally out of control. No doubt, however small the result will be, every government should take some action against drug abuse, make people way from illegal drugs and bring a steady and health society.
All kinds of illegal drugs, not only cocaine, endangers our lives. Considering the enforcement effort over illegal drugs, we should view the efforts over the total amount of marijuana, heroin, cocaine and other illegal drugs. Since many drug traffickers have consequently switched from marijuana and heroin to cocaine because of governments action, We can not tell the change on the total amount of drugs if, with the dramatic decrease of marijuana and heroin, this total amount decreased as the result of enforcement. We can claim that opposite the argument, the enforcement of effort do overawe the drug traffickers.
The argument also tells us that governments efforts to prevent illegal drugs from entering the country had effectively made drug traffickers switched form marijuana and heroin to cocaine, which means with the decrease on marijuana and heroin, the government can focus their effort on cocaine. We can see the bright future that authorities will effectively beat the cocaine traffickers just as they beat the marijuana and heroin traffickers.
So the arguments conclusion would absurd though reasoning. The authorities action did some efforts to the illegal drug abuse they should continue the enforcement against drug abuse, with efficiency.
Revised Essay
In this argument, the arguer concludes that the governments efforts to prevent illegal drugs from entering the country have resulted in an obvious increase in the illegal use of cocaine. To support this conclusion, the arguer points out that the authorities more vigilant efforts to thwart the illegal drug traffic in the country have forced drug traffickers to switch from marijuana and heroin to cocaine. In addition, the arguer reasons that the increase in the supply of cocaine has resulted in its increasing use. This argument commits two critical fallacies.
In the first place, this argument commits a fallacy of causal oversimplification. The arguer assumes that an increase in the supply of cocaine is sufficient to bring about an increase in its use. While the supply of cocaine may be one of the contributing factors to its use, it is insufficient. The presumption required to substantiate this view is that drug users are not particular about which drugs they use, so that if marijuana and heroin are not available, they will switch to whatever drug is available--cocaine in this case. This assumption is not reasonable. Marijuana, heroin, and cocaine are not alike in their effects on users; nor are they alike in the manner in which they are ingested or in their addictive properties. The view that drug users choice of drugs is simply a function of supply overlooks these important differences. Besides, the argument is self-contradictory. If it were true, as stated by the arguer, that cocaine trafficking is both safer than the bulky marijuana and more profitable than heroin that has a small market, this fact alone would have motivated the drug traffickers to switch to cocaine. In this case, the government enforcement effort should not be held accountable for the rise in the use of cocaine.
In the second place, the arguer fails to provide the necessary information based on which we can evaluate the comprehensive effect of the governments action. The background of the incident is that the drug abuse has now become ever more serious a social problem than anytime in the past. And this is what motivated the government actions against drug trafficking in the first place. We, therefore, can reasonably assume that before the government took actions the abuse of all major popular drugs had been on the trend of increase, including the use of cocaine. The newspaper editorial, however, only mentions the observed increase in the use of cocaine while failing to provide any information to specify the current increase and that before the government strengthened its drug contraction efforts. We thus cannot compare the patterns of change in this aspect before and after the government actions in order to reach any valid conclusion about the impact of the government actions on the use of cocaine.
If the trend of increase in cocaine abuse has been slowed down, or if the total amount of illegal drugs in the market has been significantly reduced, even though the absolute use of cocaine is still increasing, we would say that the government efforts in apprehending drug traffickers are somehow effective.
In conclusion, the arguer oversimplifies the cause-and-effect relationship between governments increased efforts and the observed increase in the illegal use of cocaine. To strengthen the argument, the arguer would have to provide evidence that the governments enforcement efforts have directly led to the increased supply and use of cocaine. To better evaluate the argument, we would need more information about the trend of increase in the use of cocaine and other drugs before and after the governments actions.
六、Argument典型逻辑错误
1. 调查类逻辑错误
抽样的程序是否具有随机性
样品是否足够大
Example 1:
The following appeared as part of an article in a trade magazine for breweries.
Magic Hat Brewery recently released the results of a survey of visitors to its tasting room last year. Magic Hat reports that the majority of visitors asked to taste its low-calorie beers. To boost sales, other small breweries should brew low-calorie beers as well.
Example 2:
The following appeared in a memorandum from a member of a financial management and consulting firm.
We have learned from an employee of Witful Ltd. that is accounting department by checking about 10% of the last month purchasing invoices for errors any inconsistencies saved the company some $10,000 in over-payments. In order to help our clients increase the net gains, we should advise each of them to institute a policy of checking all purchasing invoices for errors. Such recommendation could also help us get the Witful account by demonstrating to Witful the regressness of our methods.
A. The source of the news is not dependable.
B. The sample cannot reflect the general condition.
2. 错误类比
Example:
The following appeared in a memorandum from the owner of Carlos Clothing to the staff.
Since Disc Depot, the music store on the next block, began a new radio advertising campaign last year, its business has grown dramatically, as evidenced by the large increase in foot traffic into the store. While the Disc Depots owners have apparently become wealthy enough to retire, profits at Carlos Clothing have remained stagnant for the past three years. In order to boost our sales and profits, we should therefore switch from newspaper advertising to frequent radio advertisements like those for Disc Depot.
A. First, the argument rests on a fallacy of post hoc, ergo proper hoc.
B. Another problem with this argument is that it suffers from a false analogy.
3. 证据遗失类逻辑错误
Example:
The following appeared in the editorial section of a local paper.
Applications for advertising spots on KMTV, our local cable television channel, decreased last year. Meanwhile a neighboring towns local channel, KOOP, changed its focus to farming issues and reported an increase in advertising applications for the year. To increase applications for advertisement its spots, KMTV should focus its programming on farming issues as well.
A. The argument is based on a false analogy.
B. In addition, the arguer ignores other ways to increase the applications for advertising spots on KMTV.
七、逻辑问题例文分析
Case Study 4:
The following appeared in the editorial section of a corporate newsletter:
The common notion that workers are generally apathetic about management issues is false, or at least outdated: a recently published survey indicates that 79 percent of the nearly 1,200 workers who responded to survey questionnaires expressed a high level of interest in the topics of corporate restructuring and redesign of benefits programs.
Student Essay
First, the argument does not address how the nearly 1200 workers were selected, so the representativeness of the sample is doubtful. If the workers were selected by voluntary participation, then there is possibility that these voluntary workers tended to care more about management issues.
Second, the argument does not prove the credibility of the answers of the workers. It leaves open the possibility that workers who actually did not care about management issues may in a survey gave positive answers for various reasons.
Third, the argument only confines to such management issues as corporate restructuring and redesign of benefits programs, which happen to have close and main influence on workers.
Revised Essay
Based upon a survey among workers that indicates a high level of interest in the topics of corporate restructuring and redesigning of benefits programs, the arguer concludes that workers are not apathetic about management issues. Specifically, the arguer assumes that since 79 percent of the 1200 workers who responded to the survey expressed interest in these topics, the notion that workers are generally apathetic about management issues is incorrect. The reasoning in this argument is problematic in several respects.
First, the survey itself is open to question. The argument does not indicate how the nearly 1200 workers were selected. If the workers were selected by voluntary participation instead of random sampling, then there is the possibility that these voluntary workers tended to care more about management issues. In this case, the representiveness of the sample is problematic. In addition, the statistics cited in the editorial may be misleading because the total number of workers employed by the corporation is not specified. For example, if the corporation employs 2000 workers, the fact that 79 percent of the nearly 1200 respondents showed interest in these topics provides strong support for the conclusion. On the other hand, if the corporation employs 200,000 workers, the conclusion would be much weaker. Furthermore, the survey does not involve workers of other companies throughout the country.
Another problem with the argument is that it makes a hasty generalization about the types of issues that workers are interested in. It accords with common sense that workers would be interested in corporate restructuring and redesigning of benefits programs, since these issues affect workers very directly. However, it is unfair to assume that workers would be similarly interested in other management issues, ones that do not affect them or affect them less directly.
In conclusion, this argument is not convincing as it stands. To strengthen it, the arguer would have to show that the respondents account for a significant and representative portion of all workers. Additionally, the arguer must provide evidence to prove that workers do have general interest in other management topics--not just those that affect them directly.
下一篇： GMAT写作指导:如何做出作文的模版