LSAT 115 | Section 2 | Logical Reasoning: Q18

LR Question 18 Explanation

QUESTION TEXT: All historians are able to spot trends. But anyone…

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.

___________

1. 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.)
2. 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.
3. This argument makes the error of generalizing from animals with horns or antlers to “all animals.” It’s wrong, but for a different reason.
4. 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.
5. 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.

Recap: The question begins with “All historians are able to spot trends But anyone”. It is a Flawed Parallel Reasoning question. Learn more about LSAT Flawed Parallel questions in our guide to LSAT Logical Reasoning question types.