ISAT Argument Evaluation and Flaws 5 — Questions and Answers
Question 1: An argument uses a comparison between a nation's economy and a household budget to conclude that governments must never run deficits. What is the primary flaw?
- False analogy, because national economies and household budgets operate under fundamentally different rules (Correct answer)
- Circular reasoning, because the conclusion is assumed in the premise
- Ad hominem, because it attacks economists who disagree
- Slippery slope, because it assumes deficits will grow indefinitely
Correct answer: False analogy, because national economies and household budgets operate under fundamentally different rules
A false analogy applies reasoning from one domain to another where the comparison does not hold in important ways.
Question 2: Which of the following is the most valid objection to an argument that relies solely on anecdotal evidence?
- Anecdotes are always fabricated and therefore unreliable
- A single personal account may not represent the broader population (Correct answer)
- Anecdotal evidence is only valid in scientific contexts
- Personal stories are too emotional to evaluate logically
Correct answer: A single personal account may not represent the broader population
Anecdotal evidence lacks the representativeness needed to support generalisations about larger groups.
Question 3: A debater argues: 'My opponent cannot prove that my economic policy will fail, so it will succeed.' Which logical error is being made?
- Hasty generalisation
- False dichotomy
- Appeal to ignorance (Correct answer)
- Appeal to authority
Correct answer: Appeal to ignorance
Treating the inability to disprove a claim as proof of its truth is an appeal to ignorance.
Question 4: Which of the following represents a 'division fallacy'?
- Assuming that what is true of a whole must also be true of its individual parts (Correct answer)
- Assuming that what is true of each part must be true of the whole
- Using a term in two different senses within the same argument
- Claiming a correlation proves causation
Correct answer: Assuming that what is true of a whole must also be true of its individual parts
The division fallacy incorrectly transfers properties of a whole to its component parts.
Question 5: An argument states that a university's overall pass rate is high, so every department must have a high pass rate. This is an example of:
- Ecological fallacy / division fallacy (Correct answer)
- Ad hominem
- Slippery slope
- Equivocation
Correct answer: Ecological fallacy / division fallacy
Inferring individual-level outcomes from aggregate statistics is an ecological or division fallacy.
Question 6: Which of the following best strengthens an argument that a new reading programme improves literacy?
- Teachers who use the programme report enjoying it
- Literacy rates rose in the programme schools while remaining flat in comparable control schools (Correct answer)
- The programme was developed by a respected university
- Many countries have adopted similar programmes
Correct answer: Literacy rates rose in the programme schools while remaining flat in comparable control schools
Comparing outcomes in programme schools against matched control schools provides evidence that the programme—not other factors—caused the improvement.
Question 7: A newspaper headline reads: 'Nine out of ten dentists recommend BrightSmile toothpaste.' Which question is most important for evaluating this claim?
- How long has BrightSmile been on the market?
- What were the dentists asked, and was the survey sample representative? (Correct answer)
- Do dentists use BrightSmile themselves?
- Is BrightSmile available in all countries?
Correct answer: What were the dentists asked, and was the survey sample representative?
The phrasing of the question and the representativeness of the surveyed dentists are critical to assessing whether the statistic is meaningful.
ISAT Argument Evaluation and Flaws 5
An argument uses a comparison between a nation's economy and a household budget to conclude that governments must never run deficits.
What is the primary flaw?