Logical reasoning PrepTest 158 · Section 4 · Question 4

Circular reasoning is a flaw in which the conclusion merely restates a premise. They typically have this pattern on the LSAT: "X is true. We know this because, even when X doesn't appear to be true, X still must be true because X is always true." This argument doesn't rely on circular reasoning. The club president's premise is a survey, and the conclusion rules out one explanation for the club's low attendance. The conclusion is not a mere restatement of the premise.

Valid or Flawed:
Flawed

Question Type:
Errors in Reasoning

Passage Summary:
A club meets on Tuesday. Its president considers whether meeting on a different day would increase attendance. At a Tuesday meeting, 95% of the members say meeting on Tuesday is fine. So, the club president decided the low attendance was not due to scheduling conflicts.

Strategy Overview:

1. Argument or facts? Always argument, so identify premises and conclusions of argument
2. Anticipate why the premises are not enough to prove that the conclusion is true 
1. Checking to see if a common logical fallacy is committed is very helpful
3. Use anticipations to select the answer choice that:
1. Accurately describes the reason why the premises are not enough to prove that the conclusion is true

Answer Anticipation:
On an Errors in Reasoning question, we should take the time to articulate why the premise or premises aren't enough to prove that the conclusion is true. To help organize our thought process, we can think about the common fallacies that arguments commit over and over again.

When premises bring up a survey, poll, or study, an experienced LSAT-taker will immediately ask whether the argument commits a sampling fallacy. Many surveys, polls, and studies use unrepresentative samples. That just means the group survey might not represent the wider population survey/poll/study draws a conclusion about.

And that certainly is the case in this argument. The club president wants to know whether the club's low attendance is due to scheduling conflicts. So, the club surveys everyone who attended a meeting at its normal time on Tuesday. 95% of them said meeting on Tuesdays isn't a problem. From this, the club president determines the club's low attendance is not due to scheduling conflicts.

The club president's error is surveying the people who can attend the meetings (as evidenced by the fact that they showed up) to make a conclusion about people who can't attend meetings. Of course, a survey of everyone who actually showed up to the Tuesday meeting will overwhelmingly show they don’t have a scheduling conflict with Tuesday meetings. Really, the club president should survey the members who don't show up to Tuesday meetings. The club president wants to know why they can't attend meetings.

So, the correct answer will almost certainly describe this sampling flaw. It will likely say that the club president makes a generalization based on an unrepresentative sample or something to that effect.

Answer Choice Explanation: 

This describes the flaw perfectly! The author makes a generalization about the entire club's membership based on a sample of club members who attended a Tuesday meeting. This sample is likely to be unrepresentative because that sample doesn't include the members who can't attend Tuesday meetings. That's a particular issue in this argument, as the club president draws a conclusion about whether the club's low attendance at Tuesday meetings is due to scheduling issues. Note to the club president: you might want to ask the people who can't attend Tuesday meetings about that!

Key Takeaway:
Experienced test takers look for clues in the arguments of Errors in Reasoning questions to help them find the flaw committed. Premises about surveys, polls, or studies will lead an experienced LSAT-taker to ask whether the argument commits a sampling flaw.

This is tempting because the club president definitely makes a generalization. The club president assumes that the club's members generally do not have scheduling conflicts with the club's Tuesday meetings. However, the club president does not say this generalization applies "without exception." The club president's conclusion is just that the club's "attendance problem was not due primarily to schedule conflicts." This conclusion doesn’t apply to all club members; it allows for some club members to have scheduling conflicts with the Tuesday meetings.

These premises do not contradict each other. The premises assert that the club normally meets on Tuesday, and the president's survey at a Tuesday meeting reveals that 95% of the members say meeting on Tuesday is fine. Both of these premises can be simultaneously true.

The club president doesn't claim that any change is "not sufficient to solve the problem." The club president doesn't say that changing the meeting to a different date won't cause meeting attendance to increase. The president never considers what would happen if they met on a different day. Because this answer choice misdescribes the argument, it does not describe an error in the club president's reasoning.