LSAT 120 | Section 4 | Logical Reasoning: Q5

LR Question 5 Explanation

QUESTION TEXT: Sickles found at one archaeological site had scratched blades…

QUESTION TYPE: Weaken

CONCLUSION: Sickles at the first site were used to harvest grain, while those at the second weren’t.

REASONING: The first sickles were scratched, while those at the second site weren’t. Any sickles used to harvest grain will be scratched.

ANALYSIS: This argument makes an incorrect reversal. All sickles used to harvest grain will be scratched, but that doesn’t mean that any scratched sickle must have been used to harvest grain. I could scratch a sickle by banging it against a rock, for example.

The argument is correct that sickles at the second site were not used to harvest grain.

___________

1. The conclusion was that the sickles already found were used to harvest grain. It doesn’t matter if other sickles weren’t used to harvest grain.
2. CORRECT. Yes. By showing that the scratches had another cause, this answer choice weakens the conclusion.
3. The argument doesn’t claim that the sickles were used only to harvest grain, and not for any other uses.
4. This would strengthen the conclusion that the second sickles were not used for the grain harvest.
5. How something is made doesn’t necessarily tell us anything about how it is used.

Recap: The question begins with “Sickles found at one archaeological site had scratched blades”. It is a Weaken question. Learn how to master LSAT Weaken questions on the LSAT Logical Reasoning question types page.