PrepTest 128, Section 3, Question 20

Necessary AssumptionDifficulty5 of 5
The questionFull text in your LawHub copy of PrepTest 128

Professor Gandolf says that all political systems that(45 more words not shown)

Which one of the following(7 more words not shown)

Reading the argument

Gandolf's principle is broad: any political system aiming to prevent conflict is legitimate. That makes me wonder about a system that pursues peace by suppressing everyone who disagrees. The goal alone seems like a questionable basis for legitimacy.

The author offers totalitarian systems as the counterexample. They are usually good at preventing conflict, and we're told that all of them are illegitimate. At first, that seems to contradict Gandolf's rule.

But read the two descriptions again. Gandolf talks about what a system aims to do. The evidence describes what a system actually succeeds in doing. Those aren't automatically the same.

Perhaps rulers want only to preserve their own power, and reduced conflict is an incidental consequence of their control. If so, the system could prevent conflict without falling under Gandolf's rule about the aim of preventing it.

What we’re looking for

The question asks for a required assumption. To use totalitarian systems against Gandolf, we need a connection between those systems and the aim his rule mentions. Otherwise, the proposed counterexample never reaches the rule.

Working the answers

  • A

    Gandolf doesn't say that only systems with this aim can be legitimate. A legitimate system without the aim therefore wouldn't contradict his principle. More importantly, it wouldn't connect the totalitarian examples to the group his principle covers.

  • B

    This opens exactly the escape route we identified: preventing conflict is incidental rather than intended. That would undermine the use of these systems as counterexamples. It wouldn't prove Gandolf's rule true, but it would prevent this evidence from refuting it in the proposed way.

  • C
    Correct

    If at least one totalitarian system aims to prevent conflict, Gandolf's principle classifies it as legitimate. But the argument's premise classifies every totalitarian system as illegitimate. That one case is enough to contradict the universal principle.

    If none of the totalitarian systems had the relevant aim, their success at preventing conflict would not by itself challenge Gandolf. C supplies the necessary connection between the examples and the rule.

  • D

    This concerns systems that fail to prevent conflict. Gandolf's rule concerns their aim, which they could have even if they fail. D doesn't establish that any totalitarian system aims to prevent conflict, so it doesn't supply the needed connection.

  • E

    Non-totalitarian systems can be illegitimate without contradicting Gandolf. We'd still need to know that such a system aimed to prevent conflict, and E doesn't say that. It also doesn't connect the totalitarian systems used in this argument to the principle.

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