Without information that could only have come from someone present at

Question

Without information that could only have come from someone present at the secret meeting between the finance minister and the leader of the opposition party, the newspaper story that forced the finance minister to resign could not have been written. No one witnessed the meeting, however, except the minister’s aide. It is clear, therefore, that the finance minister was ultimately brought down, not by any of his powerful political enemies, but by his own trusted aide.

The argument commits which one of the following errors of reasoning?

(A) drawing a conclusion on the basis of evidence that provides equally strong support for a competing conclusion

(B) assuming without warrant that if one thing cannot occur without another thing’s already having occurred, then the earlier thing cannot occur without bringing about the later thing

(C) confusing evidence that a given outcome on one occasion was brought about in a certain way with evidence that the same outcome on a different occasion was brought about in that way

(D) basing its conclusion on evidence that is almost entirely irrelevant to the point at issue

(E) treating evidence that a given action contributed to bringing about a certain effect as though that evidence established that the given action by itself was sufficient to bring about that effect

nikhilgaur40 · Answer

Did not understand Why Option A?

itoyj · Answer

There are equal chances that the opposition leader has leaked about the meeting.

VirFortis · Answer

GMATNinja Can you please throw some light on how we arrived at option A and what is the thought process required to get to that option. I kind of eliminated all options based on my understanding of flaw being -> coincidental evidence was equated to causality and it took me 4m 54s and then guessed D. YOur explanation here would be a great help.

Thanks

Thanks

CEdward · Answer

It's weird, yes the possibility exists that the opposition was the culprit, but the way A is phrased doesn't make that clear.

A) basically says the evidence "the aide was the only person who witnessed" supports a competing conclusion (presumably that the opposition leaked the info). Awkward...

Thekingmaker · Answer

experts please explain why not E , yea A for sure after the answer why not E is , was and will be the question

sanya2711 · Answer

I think it is Option A because the argument fails to take into account that the leader of the opposition party could have also been the leak. This is correctly shown in option A.

okHedwig · Answer

Please explain how A is the answer and why not B or E. I got confused amongst the options.

AllisonBell · Answer

Great questions! We can start by mapping out this argument’s premises and conclusions:

Premises:

Newspaper story couldn’t have been written without info from someone present at the secret meeting b/t opposition leader and finance minister  
  No one witnessed the meeting except the minister’s aide

Conclusion:   The finance minister was brought down by his aide

The question asks us to identify the flaw in this reasoning. As some posters have identified, this argument is flawed because it misses the possibility that the finance minister or opposition leader could have shared the information from the secret meeting.

Because the answer choices are very abstract, it helps to make them more concrete by mapping them back onto the argument.

(A) CORRECT.  The evidence we’ve been given indicates that three people were present at the meeting. The argument draws the conclusion that the minister’s aide shared the information, but without any additional context, the evidence provides equally strong support for a competing conclusion, that the opposition leader was the leak.

(B) Let’s map this abstract answer to the text. The argument does suggest that one thing cannot occur without the other’s having already occurred: this is the reasoning that the newspaper couldn’t have been written (one thing cannot occur) without someone present at the meeting sharing information (another thing’s having already occurred). Does the argument then use that logic to assume without warrant that the earlier thing cannot occur without bringing on the later thing? This would mean that the argument assumes that a leak from someone present at the meeting (the earlier thing) necessarily caused (cannot occur without bringing on) the newspaper story to be written (the later thing). However, the argument doesn’t claim or assume that the newspaper had to publish the story because they received the leak. There’s nothing in the argument that assumes that the newspaper couldn’t have sat on the story.

(C) This answer talks about confusing evidence regarding outcomes on two different occasions. We’re not dealing with two different occasions here, though.

(D) The evidence presented is directly relevant to the conclusion. It explains the requirement that someone at the meeting leaked information in order for the story to have been published, and it indicates who was present at the meeting. All of this information directly helps us evaluate whether the aide was the person who brought down the minister via the newspaper story.

(E) This answer is suggesting that the argument confuses something that’s necessary to cause an effect with something that’s sufficient to cause an effect. The premises indicate that it’s necessary for the newspaper to have received info from someone at the meeting in order to publish the damaging story. However, the argument does not claim or imply that receiving the information was the only thing required ( sufficient ) for the newspaper to publish the story. Furthermore, this answer doesn’t get to the heart of the flaw, which is that we’ve ruled out at least one possible suspect with no evidence.

(B) and (E) are both dealing with the logical fallacy of  conflating something that's necessary with something that's sufficient . A simple example: In order to succeed in business school, I will need to take notes in classes. This establishes that it's necessary to take notes in order to succeed. Is that sufficient (enough) to be sure I'll succeed? No. But some flawed arguments might make the case that it is, and that's confusing something necessary with something sufficient.

It's hard to work through abstract answers quickly, so it helps to  pre-phrase the flaw before looking at answers,  and to  study and recognize abstract language  like  cannot occur without bringing on  or  was sufficient  that refers to sufficient v. necessary logic errors (like B and D). That way, if you've pre-phrased the flaw, you'll know the issue wasn't sufficient v. necessary, and you'll be able to rule those out based on language cues without having to spend so much time parsing them.

For more practice problems to test your logic, check out ManhattanPrep’s Free  Free GMAT QBank and Starter Kit !

Best,

KarishmaB · Answer

Premises:  
The report was written using info from someone who was at the meeting of Fin Min and Opp Leader. 
The report forced Fin Min's resignation.
Only Fin Min's aide was present additionally at the meeting.

Conclusion:  
Fin Min's aide brought him down.

Now here is the thing - are we given enough data to say that Fin Min's aide brought him down? No. We know that at the meeting, we had the Fin Min, his aide and the opposition leader. So we could use this same data to say that it is clear that the opposition leader led to his downfall. After all, the Fin Min's aide could be expected to keep his best interests in mind. 
Hence what is the error?

(A) drawing a conclusion on the basis of evidence that provides equally strong support for a competing conclusion
  
Exactly. The evidence could be used to support the competing conclusion - "It is clear, therefore, that the opp leader brought him down."
This is the flaw.

(B) assuming without warrant that if one thing cannot occur without another thing’s already having occurred, then the earlier thing cannot occur without bringing about the later thing
  
There is no necessary and sufficient conditions involved in our argument (if one thing cannot occur without another thing’s already having occurred...) Hence this option makes no sense.

(C) confusing evidence that a given outcome on one occasion was brought about in a certain way with evidence that the same outcome on a different occasion was brought about in that way

We don't have two different occasions here. We are talking about one event only. Hence this is not correct.

(D) basing its conclusion on evidence that is almost entirely irrelevant to the point at issue

The evidence is not irrelevant. The evidence tells us that only these 3 people were there at the meeting etc.

(E) treating evidence that a given action contributed to bringing about a certain effect as though that evidence established that the given action by itself was sufficient to bring about that effect

An action contributes towards a result (instead of single handedly causing the result) if there are other contributors involved too. Here there are no other contributors. The aide (as per the argument) provided the info which led to the resignation. There is no other action involved such as previous allegations against the Fin Min which strengthened the case for his resignation etc.

Answer (A)

Without information that could only have come from someone present at

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Without information that could only have come from someone present at

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