WeakenDiff: Medium
Logic Breakdown
Passage Summary: People who try to change their habits fall asleep faster than those who just take pills, so the habit-changing must be the better way to go.
Conclusion: Behavior modification is a more effective way to help people fall asleep than using sleeping pills.
Reasoning: A study showed that chronic insomniacs who used behavior modification fell asleep faster than those who only used pills.
Analysis: This argument suffers from a classic correlation-versus-causation flaw. It assumes that the method itself is the reason for the faster sleep times, ignoring the possibility that the two groups were different to begin with. To weaken this, look for an answer that suggests 'selection bias'—perhaps the people with the most severe, difficult-to-treat insomnia are the ones who gravitate toward pills, while those with milder cases try behavior modification. It's much easier to 'win' a race if you're running against a more tired opponent!
Conclusion: Behavior modification is a more effective way to help people fall asleep than using sleeping pills.
Reasoning: A study showed that chronic insomniacs who used behavior modification fell asleep faster than those who only used pills.
Analysis: This argument suffers from a classic correlation-versus-causation flaw. It assumes that the method itself is the reason for the faster sleep times, ignoring the possibility that the two groups were different to begin with. To weaken this, look for an answer that suggests 'selection bias'—perhaps the people with the most severe, difficult-to-treat insomnia are the ones who gravitate toward pills, while those with milder cases try behavior modification. It's much easier to 'win' a race if you're running against a more tired opponent!
Passage Stimulus
Passage Redacted
Unlock Full Passage9.Which one of the following, if true, most weakens the argument?
Correct Answer
D
If the people most likely to take sleeping pills are those who had the greatest prior difficulty falling asleep, then the groups differ in baseline severity. The slower sleep onset among the pills-only group could be due to their worse insomnia, not because pills are less effective. This selection bias undermines the author’s causal comparison.
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