LNAT Inference Skills 5 — Questions and Answers
Question 1: A passage states that freedom of speech protects unpopular opinions. A student concludes it therefore protects all speech without exception. This inference is:
- Valid because the passage uses the word 'all'
- Invalid because protecting unpopular opinions does not mean there are no limits (Correct answer)
- Valid by the principle of generalization
- Invalid only if the student is not a lawyer
Correct answer: Invalid because protecting unpopular opinions does not mean there are no limits
Protecting a category of speech does not eliminate all possible limits; the inference over-extends the passage's claim.
Question 2: A judge rules that a defendant's prior conviction is inadmissible. The prosecutor argues the jury should still consider it. The prosecutor's argument is:
- Valid because juries can consider any evidence
- Invalid because an inadmissibility ruling legally bars the evidence from consideration (Correct answer)
- Valid because prior convictions always show propensity
- Invalid only if the conviction was for a different offense
Correct answer: Invalid because an inadmissibility ruling legally bars the evidence from consideration
Once a judge rules evidence inadmissible, it cannot legally be put before or considered by the jury.
Question 3: Passage: 'Countries with stricter gun laws tend to have fewer gun deaths.' A commentator concludes that strict gun laws cause fewer gun deaths. Which response best challenges this?
- The commentator is wrong because gun laws never work
- Stricter laws and fewer deaths may both result from underlying cultural factors (Correct answer)
- Gun deaths are too rare to analyze statistically
- The passage is about countries, not individuals
Correct answer: Stricter laws and fewer deaths may both result from underlying cultural factors
A third variable—such as cultural attitudes toward violence—could explain both strict laws and fewer deaths without one causing the other.
Question 4: A legislator says: 'We should ban X because it has not been proven safe.' The logical problem with this argument is:
- Safety proofs are always possible for any substance
- It shifts the burden of proof: absence of safety proof is not proof of danger (Correct answer)
- Banning substances always reduces harm
- The legislator lacks scientific expertise
Correct answer: It shifts the burden of proof: absence of safety proof is not proof of danger
Requiring proof of safety rather than proof of danger reverses the standard burden of proof.
Question 5: Two witnesses give contradictory accounts of the same event. A juror concludes that both must be lying. This inference is:
- Correct because contradictions prove dishonesty
- Flawed because contradiction is also consistent with honest error or differing perspectives (Correct answer)
- Correct because eyewitness accounts are always reliable
- Flawed only if the witnesses know each other
Correct answer: Flawed because contradiction is also consistent with honest error or differing perspectives
Contradictory accounts can arise from honest mistakes, perception differences, or memory failures, not only from lying.
Question 6: A statute bans 'vehicles in the park' and a court previously ruled it covers motorcycles. An officer now wants to apply it to a child's toy car. Which reasoning method best supports the officer?
- Argument by analogy: toy cars share vehicle features the statute targets (Correct answer)
- Argument from authority: the previous ruling covers all wheeled objects
- Deductive reasoning from the dictionary definition alone
- Inductive reasoning from public opinion surveys
Correct answer: Argument by analogy: toy cars share vehicle features the statute targets
Analogical reasoning applies an established ruling to a new case by identifying shared relevant characteristics.
Question 7: A passage argues that capital punishment deters crime because crime fell after executions were reinstated. A critic replies that crime also fell in states that abolished capital punishment. This response:
- Is irrelevant because it discusses different states
- Undermines the causal claim by showing crime fell regardless of punishment policy (Correct answer)
- Proves that abolition causes crime to fall
- Supports the deterrence argument by comparison
Correct answer: Undermines the causal claim by showing crime fell regardless of punishment policy
If crime fell in states both with and without capital punishment, the punishment policy is unlikely to explain the trend.
LNAT Inference Skills 5
A passage states that freedom of speech protects unpopular opinions.
A student concludes it therefore protects all speech without exception.
This inference is: