Argument Evaluation and Flaws Flashcards

A political analyst states: 'The incumbent, Governor Smith, is sure to win re-election. A recent poll of 500 likely voters in the state's largest city showed that 65% of respondents support her.' Which of the following is the most significant flaw in the analyst's argument?

Answer: The conclusion is based on a sample that may not be representative of the entire state's electorate.

The primary flaw in the reasoning is that the poll was conducted in only the state's largest city. The views of voters in a large urban area may differ significantly from those in suburban or rural areas. Therefore, the sample is not representative of the entire state's voting population, making the broad conclusion about the election outcome unreliable. This is a classic sampling flaw.

Argument: 'Every time I wear my lucky green shirt to a football game, our team wins. Therefore, my green shirt is the reason our team wins.' This argument is flawed because it confuses...

Answer: correlation with causation.

This is a classic example of the 'post hoc ergo propter hoc' (after this, therefore because of this) fallacy. The argument incorrectly assumes that because one event (winning the game) follows another (wearing the shirt), the first event must be the cause of the second. It mistakes a simple correlation (two things happening together) for a causal relationship.

A study found that employees who take a 30-minute walk during their lunch break report higher levels of job satisfaction than those who eat at their desks. The study concluded that daily walks are an effective way to boost employee morale. Which of the following, if true, would most weaken this conclusion?

Answer: Employees who eat at their desks are often those with heavier workloads and tighter deadlines.

This answer choice introduces an alternative cause for the lower job satisfaction. If employees who eat at their desks have heavier workloads, it is likely the workload, not the lack of a walk, that is causing their lower satisfaction. This weakens the conclusion that the walk itself is the primary factor boosting morale.

A company spokesperson said: 'Our new cereal, 'Vita-Oats,' is incredibly healthy because it contains essential vitamins and minerals.' Which of the following is an unstated assumption in this argument?

Answer: The cereal does not also contain high levels of sugar and processed ingredients.

The argument's conclusion (that the cereal is healthy) rests on the premise that it contains vitamins and minerals. However, a food can contain vitamins and minerals but also be unhealthy due to other components like excessive sugar, sodium, or unhealthy fats. The argument assumes that these negative factors are not present, or are not significant enough to outweigh the benefits of the vitamins and minerals.

A scientist argues: 'We have not found any definitive proof of extraterrestrial life, despite decades of searching the cosmos. Therefore, it is almost certain that extraterrestrial life does not exist.' The reasoning in this argument is flawed because it...

Answer: treats a lack of evidence for a claim as proof that the claim is false.

This argument commits the 'appeal to ignorance' fallacy. The fact that we have not yet found evidence for something (extraterrestrial life) does not logically prove its non-existence. The absence of evidence is not evidence of absence. Our search of the cosmos is far from complete, so no definitive conclusion can be drawn from the current lack of proof.

Statement: 'Either we must increase funding for the public library, or we will condemn our community to a future of ignorance.' Which of the following best describes the flaw in this statement?

Answer: It presents a false dilemma by suggesting there are only two possible options.

This statement is a classic example of a false dilemma (or false dichotomy). It presents only two extreme outcomes (increase funding or face a future of ignorance) as if they are the only possibilities. It ignores a wide range of other potential options, such as maintaining current funding levels, reallocating existing funds more efficiently, or finding alternative sources of knowledge and education within the community.