QUESTION TYPE: Flawed Parallel Reasoning
CONCLUSION: Anyone who can distinguish the significant from the insignificant is a historian.
REASONING: Historians can spot trends. Any anyone who can spot trends can distinguish the significant from the insignificant.
Diagram: H ➞ ST ➞ D
(Flawed Conclusion) Therefore anyone who can D is an H.
ANALYSIS: I guess we’re all historians? This argument presents a straightforward example of incorrect reversal. You can’t prove a sufficient condition with a necessary condition.
___________
- CORRECT. FS ➞ EI ➞ P. If a poet says “Hello,” that doesn’t make it a figure of speech. This argument makes an incorrect reversal. It states that the necessary condition (P) proves the sufficient condition (FS.)
- This is almost a good argument, except that there may be a middle ground between “autocracy” and “democracy.” The argument goes left to right, from sufficient to necessary. We’re looking for a bad argument, going from right to left.
- This argument makes the error of generalizing from animals with horns or antlers to “all animals.” It’s wrong, but for a different reason.
- There might be some other reason a short story writer couldn’t become a musician (they’re tone deaf?) This is a bad argument, but it is a different error.
- This is a good argument. We have to wear neckties thanks to some jerk of a tailor who lived centuries ago. We are not fully free.
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