Logical ReasoningDifficulty: Easy

PT137 S4 Q7 Explanation

Even though MacArthur's diet book

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

TopicsPrinciple-Strengthen

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Stimulus

Even though MacArthur's diet book helped many people lose weight, MacArthur should not have published it. It recommended such small portions of fruits and vegetables that it undoubtedly damaged the health of many who followed the diet. MacArthur is a physician, so that diets low in fruits and vegetables are unhealthful.

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
7.

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

Answer choices

  1. Trap2% picked this

    One should not undertake an action if one knows that doing so would seriously damage the

  2. Trap0% picked this

    One should not follow a particular method for achieving some end if doing so has the potential

  3. Trap1% picked this

    One should publish a book recommending certain health-related measures if doing so is likely to improve many people's

  4. Trap1% picked this

    One should not publish a book recommending a particular means of attaining a goal unless one knows that the particular means

  5. Correct95% picked this

    One should not publish a book recommending a particular course of action if one either knows or ought to know that taking that

    Why this is right

    Answer E is correct.

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

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