Logical reasoning PrepTest 147 · Section 1 · Question 18

Correct. Argument or Facts:
Argument

Valid or Flawed:
Flawed

Question Type:
Strengthen with Necessary Premise

Stimulus Summary:
Survey Ð Almost all scientists accept Wang's Law and know the BE Experiment
Science Ð Wang's Law + BE Experiment = Minsk Hypothesis is wrong!
Conclusion Ð Almost all surveyed scientists reject the Minsk Hypothesis

Answer Anticipation:
A survey is done here, so we should start with checking for a sampling flaw and a correlation/causation flaw. However, the conclusion is about the surveyed scientists, and it isn't causal, so neither of them are present.

However, there is another huge flag for a certain flaw—the argument keeps talking about what these scientists accept/know/reject. That's a subjective assessment, and so we should check to see if there are any problematic shifts there.

Here, the argument establishes that the scientists know two things—Wang's Law, which they accept, and the results of the BE Experiment, which we don't know if they accept. It also brings up something that's true—Wang's Law and the BE Experiment together contradict the Minsk Hypothesis—but it doesn't establish if the scientists in the survey are aware of this. Since the argument fails to establish their knowledge of this contradiction, we can't assume they know it—so let's see if the argument relies on them knowing it.

The conclusion is about rejecting that hypothesis, so the argument does, indeed, assume that the scientists are aware of the contradiction. This jump between something that's true and people accepting the implications of it as if they were aware of it is problematic. The correct answer should highlight that the scientists know that Wang's Law and the BE Experiment contradict the Minsk Hypothesis.

Answer Explanation:
This answer wholly matches our anticipation. If the scientists aren't generally aware of this contradiction, then it can't be assumed that they reject the Minsk Hypothesis based on it.

Key Takeaway:
Whenever an argument starts talking about what a group or individual thinks, believes, or knows, check to see if it starts assuming knowledge of other things. A mix of true and believed statements can create issues in an argument. Just because something is true doesn't mean people know or believe it, and just because something is believed doesn't mean it's true.

Incorrect. This answer is related to an overlapping sets flaw. And while the argument does take two "almost all" statements and concludes a "most" statement from it, requiring a large amount of overlap between the two sets, it doesn't need all ("exactly") of the two noted groups to overlap. If almost all of them overlap, then it could still be that most of the scientists fit into the group that accepts Wang's Law and knows of the BE Experiment.

Incorrect. The scientists don't need to be aware of the experimental design of the BE Experiment to know the results or to accept those results. There are plenty of scientific facts that we, as a society, accept without knowing how experiments proving them were designed.

Incorrect. If the conclusion were about scientists in the field, then this answer would be correct. However, the conclusion is about "the scientists surveyed," and so there's no sampling flaw.

Incorrect. Since the conclusion is about scientists's beliefs as to the truth of the Minsk Hypothesis, it doesn't matter if the underlying beliefs leading to it are true as long as scientists accept them as true.