Quiz 10: Looking for Errors in Reasoning

Copyright 2002 © Laraine Flemming.
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Directions: Read each passage. Then circle the appropriate letter to indicate either an error in reasoning or the absence of any error.


1.The Census of 2000 revealed significant and striking changes in the structure of American families. In 1960, 45 percent of households were traditional; in other words, they included a married couple with children. In 2000, a low 23.5 percent of all United States households contained a nuclear family. In 1940, less than 8 percent of households were occupied by people living alone. In 2000, that number had climbed to 26 percent. The number of unmarried couples living together has also increased dramatically. In just ten years' time, from 1990 to 2000, the number of cohabitating couples rose 72 percent; now, 5.4 million people, or about 5 percent of all households, live together out of wedlock. In the 1960s and 1970s, unmarried couples inhabited just one percent of households. The number of families headed by single female parent has also grown. In 1950, only 6 percent of family households were headed by single mothers, but by 2000, that percentage had increased to 22 percent of all families with children.

Error:   a. attacking the person rather than the reasoning
  b. including irrelevant facts
  c. relying on a slippery slope
  d. no error


2. Suppressing pornography actually does more harm than good. First, censoring or restricting pornography violates the First Amendment to the United States Constitution, which guarantees freedom of speech. Though pornography may be offensive, undermining freedom of expression—a fundamental right in a democratic country—by censoring it is a far greater threat. Second, suppressing pornography actually argues against equality between men and women. Some people claim that pornography should be suppressed because it promotes discrimination against women. However, this argument suggests that women are victims who need more protection than men. Women cannot achieve full equality if laws single them out as a category of people, like children, who require special consideration. Third, the anti-pornography movement also works against women by providing men who commit violent sexual acts with a convenient excuse for their behavior. If a man can argue that pornography drove him to his crime, he can sidestep the issue of his own personal responsibility. Finally, if we censor pornography, there's no telling where the censorship would stop, and our local libraries would be stripped of all books containing any sexual content.

Error:   a. attacking the person rather than the reasoning
  b. including irrelevant facts
  c. relying on a slippery slope
  d. no error


3. Background checks and waiting periods for those who wish to purchase guns should be eliminated because they don't deter criminals and because they inconvenience law-abiding citizens. According to the Department of Justice, about 87 percent of violent crimes occur outside the home. That same agency reports that police respond to calls for help within 5 minutes only about 28 percent of the time. Furthermore, a study that analyzed data from all counties in the United States for the period of 1977-1992 found that those allowing their citizens to carry weapons saw a 7.65 percent reduction in murders, a 5.2 percent drop in rapes, and a 2.2 percent decrease in robberies.

Error:   a. attacking the person rather than the reasoning
  b. including irrelevant facts
  c. relying on a slippery slope
  d. no error


4. Congressman Bob Bly has sponsored a bill to establish America's first "official secrets act." If passed, this law would make it a felony for federal employees to reveal classified information of any kind, even when that information relates to abuse or potential danger. Bob Bly apparently expects this country's citizens to ignore the fact that he kept plenty of secrets of his own about his extramarital affair with an intern who worked in his office. He wants us all to forget about how he evaded the accusations of infidelity. He probably wants his "official secrets act" to pass so his own employees can't leak information about his personal activities.

Error:   a. attacking the person rather than the reasoning
  b. including irrelevant facts
  c. relying on a slippery slope
  d. no error


5. Polls show that at least a third of Americans favor the decriminalization of marijuana. However, legalizing this drug would be very dangerous. Young people who discovered the joys of getting high from marijuana cigarettes would soon seek out harder drugs such as cocaine and heroin. Before long, they would become addicted to these drugs, and they would probably start abusing alcohol, too. In a short time, their lives would be ruined as they focused all of their efforts on purchasing drugs so they could stay high all of the time. And it would all begin with a few puffs of legal marijuana.

Error:   a. attacking the person rather than the reasoning
  b. including irrelevant facts
  c. relying on a slippery slope
  d. no error



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