LSAT 128 | Section 2 | Logical Reasoning: Q25

LR Question 25 Explanation

QUESTION TEXT: Although Stillwater Pond has been polluted by farm runoff …

QUESTION TYPE: Flawed Reasoning

CONCLUSION: The fishing guide believes that the bullhead catfish has adapted best to polluted water.

REASONING: He states that the most populous fish is the one that has adapted best to pollution. Recent studies suggest the most populous fish is the bullhead catfish.

ANALYSIS: The link goes something like this (premise about guide’s belief) -> (premise from recent study) -> (conclusion about guide’s belief).

The argument assumes the fishing guide agrees with the recent studies (that the bullhead catfish is the most populous species). But he may have a different belief. So the best answer will highlight this unjustified assumption that the guide accepts the study’s findings.

___________

1. The fishing guide’s belief about pollution is not in question. It’s his belief about which species is most populous and therefore best adapted to pollution that’s the focus.
2. The species’ biology is irrelevant to the argument’s flaw, which is about the fishing guide’s belief.
3. This is not the flaw. The studies could be right or wrong and he could still disagree with them. That’s why the flaw is assuming the guide agrees with them.
4. CORRECT. The argument assumes the guide accepts that bullhead catfish are the most populous species, but the guide may actually believe a different fish is most populous.
    
   For example, if he believed goldfish were most populous, the correct conclusion would be that he believes goldfish are best adapted to pollution, not bullhead catfish.
5. The argument does not assume there is only one species of catfish.