QUESTION TEXT: Any popular television series that is groundbreaking…
QUESTION TYPE: Parallel Reasoning
CONCLUSION: Not all popular TV series are groundbreaking.
REASONING: Groundbreaking —> critically acclaimed
Contrapositive: not critically acclaimed —> not groundbreaking
Some popular TV series are not critically acclaimed.
ANALYSIS: This is a good argument. It uses the contrapositive of a conditional statement to draw the conclusion. The contrapositive looks like this: not critically acclaimed —> not groundbreaking
The conclusion is the necessary condition of the contrapositive. So, look for a single statement, its contrapositive, and a conclusion that proves the necessary condition of the contrapositive. You can eliminate two answers for being wrong, and two for being good but not using the contrapositive.
___________
- This is a good argument, but it doesn’t use the contrapositive.
Structure: Academic articles —> Specialized tech —> not widely read
Conclusion is academic articles are not widely read - This is an incorrect reversal.
Structure: Think improved —> high grades
The conclusion is “think improved”, which is the sufficient condition. We can never conclude the sufficient condition. - CORRECT. This works. It uses the contrapositive like the stimulus. Evidence: Unbiased —> embarrassing facts. Contrapositive: no embarrassing facts —> not unbiased
The conclusion says “not unbiased”, using “no embarrassing facts. - This is a good argument, but like A it merely applies the conditional without the contrapositive. Two answers with identical structure can’t both be right!
Structure: Person polite —> Schwartz polite back
Colleagues are polite, therefore Schwartz polite. - This is an incorrect negation. It negates both sufficient and necessary, without reversing. You can’t do that.
Structure: Book worth reading —> worth buying
not worth reading —> not worth buying
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