Flawed ReasoningDiff: Easy
Logic Breakdown
Passage Summary: A researcher noticed that areas with many different types of plants were healthier and concluded that the variety of plants is what caused the health boost.
Conclusion: Increasing the number of plant species in a prairie directly improves its ability to support plant life.
Reasoning: A study observed that prairie plots with a higher variety of species also exhibited more vigorous plant growth and better soil nutrient retention.
Analysis: The argument falls into the 'Correlation vs. Causation' trap. Just because high species diversity and healthy soil are found together doesn't mean the diversity caused the health. It is just as plausible that healthy, nutrient-rich soil is what allowed a diverse range of species to thrive in the first place. When analyzing this flaw, look for an answer choice that points out the possibility of the causal relationship being reversed or both factors being caused by a third variable.
Conclusion: Increasing the number of plant species in a prairie directly improves its ability to support plant life.
Reasoning: A study observed that prairie plots with a higher variety of species also exhibited more vigorous plant growth and better soil nutrient retention.
Analysis: The argument falls into the 'Correlation vs. Causation' trap. Just because high species diversity and healthy soil are found together doesn't mean the diversity caused the health. It is just as plausible that healthy, nutrient-rich soil is what allowed a diverse range of species to thrive in the first place. When analyzing this flaw, look for an answer choice that points out the possibility of the causal relationship being reversed or both factors being caused by a third variable.
Passage Stimulus
Passage Redacted
Unlock Full Passage9.The argument is most vulnerable to criticism on the grounds that it
Correct Answer
A
A correctly flags the correlation-to-causation leap in a specific way: it notes the argument infers X causes Y without considering whether Y might cause X. Here, the author assumes biodiversity causes productivity/soil retention, ignoring the possibility that more productive, nutrient-retentive plots are what allow more species to persist.
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