Logical ReasoningDifficulty: Hard

PT125 S4 Q9 Explanation

The Jacksons regularly receive

A free, expert breakdown of this official LSAT Logical Reasoning question.

TopicsPrinciple-Strengthen

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Stimulus

The Jacksons regularly receive wrong-number calls for Sara, whose phone number was misprinted in a directory. Sara contacted the Jacksons, informing them of the misprint and her correct number. The Jacksons did not lead Sara to believe that they would pass along the correct number, but it would be helpful to Sara the wrong number, it would be laudable if the Jacksons passed along Sara's correct number.

What this question is testing

Principle-Strengthen

Your task

Break the argument into its conclusion and evidence, then do exactly what the question stem asks with that structure.

Common trap

Answers that sound relevant to the topic but don't connect to the argument's actual reasoning.

Winning move

Predict what a right answer must do, then test each choice against the conclusion-evidence gap.

Reading along? Open the full official question in LawHub — we show a fragment here and keep the reasoning in our own words.

The question
9.

Which one of the following principles, if valid, most helps to justify the reasoning

Answer choices

  1. Correct53% picked this

    It is always laudable to do something helpful to someone, but not doing so would be wrong only if one has led that person

    Why this is right

    Since passing along Sara’s number would be helpful, this ensures that it would be laudable if the Jackson’s passed along her number. And by contrapositive, since the Jackson’s did not lead Sara to believe that they would pass along her number, it would not be wrong if the Jackson’s did not pass along her number.

    Skill tested: Principle-Strengthen · how this choice captures the argument's function is the move to repeat next time.

  2. Too Weak5% picked this

    Being helpful to someone is laudable whenever it is not wrong

    This fails justify the part of ~PA → ~W the conclusion that says that it would not be wrong if the Jackson’s were not helpful (i.e., did not pass along Sara’s number).

  3. Too Weak36% picked this

    If one can do something that would be helpful to someone else and it would be easy to do, then it is laudable

    This fails justify the part of ~PA → ~W the conclusion that says that it would not be wrong if the Jackson’s were not helpful (i.e., did not pass along Sara’s number).

  4. Reversal1% picked this

    Doing something for someone is laudable only if it is difficult for one to do so and it is wrong for

    This makes laudable a trigger L → D + W of a relationship, whereas the reasoning in the argument makes it an outcome of a relationship.

  5. Reversal4% picked this

    The only actions that are laudable are those that it would not be wrong to refrain from doing, whether or not it

    This makes laudable a trigger L → ~W of a relationship, whereas the reasoning in the argument makes it an outcome of a relationship.

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