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LSAT Explanations › Preptest 107 › Logical Reasoning › Question 18

LSAT 107 | Section 4 | Logical Reasoning: Q18

LSAT Preptest 107 explanations

LR Question 18 Explanation

QUESTION TEXT: All actions are motivated by self-interest, since…

QUESTION TYPE: Flawed Reasoning

CONCLUSION: All actions are motivated by self-interest.

REASONING: Even actions that are apparently altruistic can be described in terms of self-interest. For example you might help someone because you’re hoping to get a reward.

ANALYSIS: This argument isn’t convincing. It only said helping another person “can” be described as self interested. But it might be wrong to describe an action that way, even if you “can” do it.

___________

  1. Self-interest always means the same thing: looking out for your own benefits.
  2. CORRECT. The argument only said that helping someone “can” be described in terms of self-interested. It hasn’t proven that it ought to be described as self-interest. 
  3. We don’t need to explain those terms. Most people know what they mean.
  4. This answer may sound tempting, because it uses words from the argument. But it describes something the argument didn’t do. Where did the author claim anything was a necessary condition “for a certain interest to be a motivation?”
  5. The argument goes beyond emotion. It tries to show logically that all actions are self-interested. 
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More Resources for Flaw Questions

  • Flaw drills: Use these to practice making examples of abstract flaws.
  • Intro Course lesson: This intro course lesson covers Flaw questions.
  • Mastery Seminar lesson: This LR Mastery seminar lesson covers flaw questions.
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