PrepTest 133

Correct. Argument or Facts:
Argument

Valid or Flawed:
Flawed

Question Type:
Flawed Parallel Reasoning

Stimulus Summary:
Taxes should be proportional to how much society serves one's interests, which is best measured by wealth, so we should tax only income.

Answer Anticipation:
Personal philosophies towards taxation aside, this argument brings up a brand new term in the conclusion—income. The premises are about taxing wealth, not income, and while there is some relationship between the two, they are not the same thing. Just ask any retired lottery winner!

The correct answer should similarly shift between establishing that one thing can serve as a good measure, but then conclude that a related but distinct thing should be used.

Answer Explanation:
This argument establishes that speed is a good measure for danger, but then it reaches a conclusion about acceleration—related to speed, but distinct. This answer commits the same flaw, so this is the correct answer.

Key Takeaway:
Always be on the lookout for new terms or concepts in the conclusion. When one shows up, there's a good chance that the argument is shifting from one idea to another without establishing that connection.

Incorrect. The premises in this argument are about using a test to measure maturity, and the conclusion is also about that test, so this answer doesn't have the same term shift.

Incorrect. This answer has a matching topic, which is always suspicious. The flaw here is that the conclusion jumps to a comparative statement ("greater share") when the premise doesn't allow for that comparison (there's no discussion of benefits received by individual citizens).

Incorrect. This answer features a "should" in each statement, which throws the logic off. It also shifts from discussing individuals who work to benefit society in the premise to taxing those activities, which is a different shift than the stimulus.

Incorrect. This argument doesn't introduce a new term in the conclusion, so it doesn't commit the same flaw as the stimulus.