QUESTION TYPE: Flawed Parallel Reasoning
CONCLUSION: Small farms ➞ Returning waste good
REASONING: returning waste good ➞ nontoxic AND not much energy
Small farms ➞ nontoxic AND not much energy.
ANALYSIS: This argument make an incorrect reversal. The argument gives us necessary conditions for saying that returning waste is good. And we know small farms meet those necessary conditions.
But you can never prove something with necessary conditions. To prove that returning waste is good, we would need a sufficient condition. And the argument hasn’t given us a sufficient condition.
The conclusion reverses the evidence and assumes that anything that meets the two conditions is good. So we’re looking for an argument:
- A conditional statement
- A situation that meets the necessary conditions
- An incorrect reversal of the statement
- This is a good argument. The conditional statement gives a sufficient condition for thriving, and greenhouses meet that condition.
- This is a good argument. It provides a sufficient condition.
- CORRECT. This matches. We have necessary conditions for viability. The argument reverses this and assumes they are sufficient conditions.
- This is a good argument. It gives a set of sufficient (and necessary) conditions, so meeting the conditions proves the conclusion.
- This is a bad argument. It would be good if it showed the meal had no carbohydrates and protein. But this argument didn’t do that – the 20% remainder of the meal might have had both carbs and protein.
This is failure to meet a condition. It’s not an incorrect reversal, which was the error in the argument.
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