Logical reasoning PrepTest 127 · Section 3 · Question 4

Correct. Argument or Facts:
Argument

Valid or Flawed:
Flawed

Question Type:
Errors in Reasoning

Stimulus Summary:
NoSmoke: Our product reduces nicotine cravings!
Study - When tested, the main ingredient didn't have this effect.
Fact - NoSmoke has only 2 ingredients.
Conclusion - If the other ingredient, when tested, doesn't have the effect, then NoSmoke doesn't reduce cravings.

Answer Anticipation:
This argument is interesting in that the conclusion essentially adds in an additional study as a condition for it holding true! So for the purposes of analyzing the logic, let's start by saying that a study was done and the other ingredient also didn't have the effect of cutting down on people's nicotine cravings.

So Study 1 shows ingredient A doesn't work by itself, and Study 2 shows ingredient B doesn't work by itself. What possibility is that ignoring? That the ingredients only work when taken together!

It'd be like concluding that baking soda doesn't make a volcano, and vinegar doesn't make a volcano, so thus baking soda + vinegar doesn't make a volcano.

The answer talks about the individual ingredients of a medication, which should have led you to think about a parts vs. whole flaw, so let's find an answer that phrases this issue in those terms.

Answer Explanation:
This answer is the whole vs. part flaw that is committed by the argument. Just because the individual parts (ingredients) of something (NoSmoke) lack a certain quality (reduces cigarette cravings), that doesn't mean the whole also lacks that quality. This answer is therefore correct.

Key Takeaway:
Whenever an argument brings up a word that inherently refers to a part of something larger (ingredient, individual, citizen—a part of society, cell—a part of the body), start to think about part vs. whole flaws.

Incorrect. The conclusion is that something doesn't serve as a cause for a given effect, so there's not a correlation/causation flaw here.

Incorrect. There's no indication that the sample in the study was unrepresentative—they studied smokers, and the conclusion is about that group.

Incorrect. The conclusion is limited to the effect NoSmoke has on cravings. If the answer was broader and had stated that NoSmoke doesn't help people quit smoking, then this answer would be correct.

Incorrect. The argument uses a study to rebut the claims made by NoSmoke, not that those individuals are biased.