Logical reasoning PrepTest 109 · Section 3 · Question 15

Correct. Argument or Facts:
Argument

Valid or Flawed:
Flawed

Question Type:
Errors in Reasoning

Stimulus Summary:
Situation — Scientists launched a spacecraft to study ozone damage and reverse it

Environmentalist: The spacecraft polluted as much as a factory in a year. The factory's pollution is unjustifiable, so the spacecraft is, too.

Answer Anticipation:
The argument by the Environmentalists relies on a comparison between the spacecraft and another situation—the average factory in a year. The two are established as polluting the same amount, which is also established as being unacceptable in the case of the factory. From this, the Environmentalists conclude the same thing about the spacecraft—it's unjustifiable.

When an argument uses similarities between two situations to reach a similar conclusion about the two, then it needs to establish that the similarities in the premises are the only relevant points of comparison. Here, they don't—and, in fact, there's a reason to believe that the spacecraft was relevantly different from the factory. It's noted that the purpose of the spacecraft was to study the ozone layer to eventually reverse damage done to it—factories wouldn't have the same environmental goal.

Let's find an answer that establishes the two situations are relevantly different—it may or may not bring up the specific difference that the stimulus notes.

Answer Explanation:
This answer doesn't specifically mention the difference noted in the stimulus, but it does bring up the error in reasoning. The Environmentalists treat the case of the spacecraft and the average factory as similar with respect to the justifiability of their pollution when they are different in a key respect—their environmental goals.

Key Takeaway:
Whenever an argument relies on two things being similar, check to see if it's possible there are relevant differences between the situations.

Incorrect. The conclusion is about the single spacecraft launch, so it's not a generalization.

Incorrect. If anything, the Environmentalists focus on preventing the effects (by condemning the spacecraft launch and the factories) while ignoring the potential to reverse the harmful effects. As such, they don't fail to distinguish between them.

Incorrect. The amount of harm done to the ozone layer is a quantifiable amount that can be compared, so they're comparable in at least some way.

Incorrect. The Environmentalists limit their discussion of experiments to the single one mentioned in the stimulus, so this answer doesn't reflect their argument.