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#22640
Question #12: Flaw—SN. The correct answer choice is (D).

The author of this stimulus presents a number of conditional statements, and draws a flawed conditional conclusion.

The stimulus begins with the Duke’s argument that only virtuous Acredian rulers concerned with the well-being of the people will be able to rule successfully. Since “only” is a necessary condition indicator, this statement can be diagrammed as follows:

Rule successfully :arrow: Concern for welfare

The author concludes that this argument is valid, because whenever Acredian governments have fallen (i.e. whenever the rulers were not successful), their falls have always coincided with a ruler who disregards the people’s needs (i.e. a ruler who was not concerned with the well-being of the people). Note the importance of seeing the logical equivalence between a “fallen government” and an “unsuccessful ruler,” and also between “disregarding people’s needs” and the “lack of concern with the well-being of the people.” These are clearly synonymous expressions, but the difference in language makes the underlying logical fallacy harder to spot:
Premise: NOT Rule successfully :arrow: NO Concern for welfare

Conclusion: Rule successfully :arrow: Concern for welfare
This is a classic error in conditional reasoning, known as a Mistaken Negation. The question stem asks us to describe it in abstract terms, which would be difficult to do without using the requisite terms of conditional reasoning (e.g. “sufficient,” “necessary,” or a synonym). Note, however, that the use of such terms alone does not automatically make a given answer choice correct, nor does their absence guarantee that the answer choice is incorrect.

Answer choice (A): The author argues that concern for the welfare of the people is necessary for successful governance, but never discusses what this concern actually entails. This answer choice outlines a possibility that falls outside the scope of the argument.

Answer choice (B): This is an attractive answer choice, as it comes very close to describing the Mistaken Negation we are looking for. However, note that the author infers the necessity of a certain condition for success from the fact that its absence has always associated with, not led to, failure. The difference is minor but crucial, as no overt causal relationship between the two is ever asserted: disregarding people’s needs may correlate with failure, but it does not necessarily lead to failure. This answer choice fails the Prove Test and is therefore incorrect.

If you failed to notice this slight shift in language upon initial inspection, it would have been wise to leave this answer choice as a Contender and move on. You would have quickly realized that answer choice (D) makes a similar claim, forcing you to examine how the two choices differ in their description of the logical flaw.

Answer choice (C): The author makes no appeal to evidence from biased sources. Even if the Duke’s argument has the potential for bias, the author does not appeal to it in reaching her conclusion. She only claims that he was right, an observation she reaches by appealing to the historical evidence that (presumably) bears it out. Of course, had you noticed the Mistaken Negation early on, eliminating this answer choice would have been a no-brainer.

Answer choice (D): This is the correct answer choice, as it describes the Mistaken Negation reflected in the stimulus. The author infers that a certain condition (concern for the welfare of the people) is required for successful governance from the fact that the lack of that condition (rulers disregarding people’s needs) is associated with failure. The two occurrences are correlated, which is precisely why their relationship is properly described as an association, not a causation, as answer choice (B) erroneously contends.

Answer choice (E): Hopefully you were able to eliminate this answer choice relatively quickly, as author makes no assumptions about whether the character of past rulers can be objectively assessed.
 15veries
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#30192
For B, isn't it also true that the answer choice confuses "infer from X...that Y"? It should be infer from Y that X...
Infer from Premise that Conclusion but this answer is saying infer from Conclusion that Premise.?
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 Jonathan Evans
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#30460
Hi, 15Veries,

If I'm following your question correctly, I think perhaps are misinterpreting the syntax of this answer choice.

The explanation above is excellent, but let me try to parse out this answer choice B for you:

(B) infers the necessity of a certain condition :longline: this is what the conclusion claims, that concern for welfare is necessary for government success :longline: from the fact that's its absense has always led to failure :longline: this is a misstatement of the premise, as explained above the premise includes no statement about lack of concern for welfare leading to or being sufficient for failure; instead, the premise only suggests a correlation between lack of concern for welfare and failure.

I hope this helps!
 nutcracker
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#39786
Hi,

I have a question about the "Premise: NOT Rule successfully :arrow: NO Concern for welfare" part in the first explanation. From the stimulus we only know that a failed government is always associated with the ruler disregarding the people's needs, but can we safely draw a conditional relationship from a correlation like this? If not then the flaw wouldn't really be a mistaken negation, since we need to have two conditional relationship statements to have a mistaken negation... I'm a bit confused. Thanks in advance for helping!
 nicholaspavic
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#39816
Hi nutcracker,

This is a great question and one that is really getting into a deeper level that the answer choices bring up. The correlation described and diagrammed above is properly diagrammed as sufficient and necessary and oftentimes on the LSAT, we will have to convert correlations to conditionals because causality has not been established. In fact, this is quite frequent on the LSAT where we are called upon to examine the language in order to make a determination about its underlying logic. Aside from Flaw questions, oftentimes, Assumption type questions express correlations like "among multiparty democracies, those with the fewest parties will have the most productive legislatures." It's important to recognize always that correlation does not equal causation, but that correlation can still be validly expressed in conditional logic. That's also why Answer (D) works here because it recognizes that the only way to express the logic of this stimulus is in the conditional.

Thanks for the great question and I hope this helped.
 Leela
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#65002
Is the Prove Test, mentioned in the Administrator explanation, the same as the Fact Test?
 Rachael Wilkenfeld
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#66859
Hi Leela,

Yes. They both refer to the process of trying to prove the answer choice using the stimulus in a must be true situation. In a must be true question, you have to find the answer choice that is provable based on the stimulus.

Hope that helps,
Rachael
 StudyEveryday
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#78850
Hi,

I am curious why it would not be Concern --> Successfully? I thought the "only" would make "concerned" a necessary?

Thank you
 Rachael Wilkenfeld
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#79057
Hi Study,

The term "only" here modifies the necessary condition, which is typically directly following the term only. Here, the concern follows the necessary indicator "only" and the other term (successful rule) becomes our sufficient condition. As you said, the concern in the necessary condition. I think you may just be diagramming backwards---you seem to recognize that concern is necessary, but your conditional drawing is flipped from how it should be for that relationship. Remember in the diagram, the sufficient always comes before the arrow, and the necessary comes after.

Hope that helps!
Rachael
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 goingslow
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#94479
Hi! So is it fair to say that conditional logic can indicate association/correlation, but not causation?

Thank you so much!

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