LSAT 128 | Section 2 | Logical Reasoning: Q23

LR Question 23 Explanation

QUESTION TEXT: Some people believe there is intelligent life somewhere …

QUESTION TYPE: Parallel Reasoning

CONCLUSION: Some people do not believe that all planets other than Earth are devoid of life.

REASONING:

1. Some people believe there is intelligent life somewhere outside of Earth.
2. No one who believes that could also believe that all other planets are devoid of life.

ANALYSIS: This follows a basic structure. Some people believe X. No one who believes X could also believe Y. Therefore, some people do not believe Y.

The correct answer will mirror this logical structure, so keep this in mind when you’re reading through the answer choices.

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1. This reasoning is actually flawed because it jumps from people’s beliefs to a factual conclusion. The original argument only makes an inference about what people believe, not about what the reality actually is.
2. This is very close, but it doesn’t match exactly. The stimulus requires a belief that necessitates rejecting another belief, whereas this answer involves a belief that requires a prerequisite belief (thinking an animal feels guilt -> thinking it has morality).
3. CORRECT.
   • Some dog owners believe X
   • No one who believes X could also believe Y
   • Therefore, some dog owners do not believe Y

   This perfectly mirrors the reasoning in the stimulus.

4. This is actually a flawed argument, and not the same structure as the stimulus. This says:

   • Some people believe X
   • Anyone who believes X must also believe Y
   • Therefore, some people do not believe Y

   This doesn’t logically follow. Just because some people believe X and those people must also believe Y, this is not enough to conclude that some people must reject Y.

5. Like A, this makes a false jump to a factual conclusion.