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Complete Question Explanation

Flaw in the Reasoning—SN. The correct answer choice is (A)

The stimulus contains a series of conditional statements, and the logical flaw results from how these statements relate to each other. To fully describe how this flaw occurs takes a bit of effort, and some patience on your part.

Note that the first sentence in the stimulus is the conclusion. While there is no explicit conclusion indicator identifying the first sentence as the conclusion, it is supported by the second sentence, which begins with “for,” a premise indicator.

The conclusion is that humorous television advertisements are the only effective ones. This is a very restrictive conclusion, and can be restated as “television advertisements must be humorous in order to be effective.” Using “E” for “effective” and “H” for “humorous:”

The connection between humor and effectiveness offered by the argument has to do with the ability of an advertisement to convey its message. This connection is seen most clearly by beginning with the last sentence of the stimulus, which tells you that an advertisement must convey its message (“CM”) to be effective. This also is a conditional relationship:

The second sentence in the stimulus is a premise providing the conditional relationship that if something is humorous (“H”), then it will hold a person’s attention long enough for a message to be conveyed (“HPA-CM”):

H HPA-CM

The conclusion results from a Mistaken Reversal of this conditional relationship in the second sentence. Instead of the relationship actually contained in the second sentence, just described as

H HPA-CM

the argument treats this term as

HPA-CM H

This presents a bit of difficulty, because we now need to consider this new, mistaken relationship from the perspective of its contrapositive to fully understand the implications of the mistake. The contrapositive is:

H HPA-CM

This representation provides that “if something is not humorous, then it cannot hold people’s attention long enough for a message to be conveyed.” Taking this a step further, if something cannot hold people’s attention long enough for a message to be conveyed, then it will not, in fact, convey its message. So, an inherent implication of this Mistaken Reversal is this relationship:

H CM

The contrapositive of this relationship is:

CM H

While rather tedious, this more in depth examination of the Mistaken Reversal was necessary, because it provides us with the term:

(CM H)

used by the stimulus to reach the conclusion. So, all together, this is the invalid argument contained in the stimulus:

Premise: CM H (the result of the Mistaken Reversal)

So, your prephrase in this Method of Reasoning—Flaw question is that the argument is flawed because it assumes the Mistaken Reversal of the relationship in the second sentence: it treats being humorous as if it were necessary to convey a message, when the premise actually provided that being humorous is sufficient to hold people’s attention long enough for a message to be conveyed.

Answer choice (A): This is the correct answer choice, because it describes the Mistaken Reversal detailed above. In this choice, the phrase “nothing but humor” indicates that humor is necessary for something to attract a person’s attention and hold it long enough for a message to be conveyed.

Answer choice (B): This choice is incorrect because it is inconsistent with the stimulus. In the second sentence, the stimulus expressly treated attracting a person’s attention as distinct from holding a person’s attention long enough for a message to be conveyed.

Answer choice (C): In the last sentence of the stimulus, the condition presented as necessary for an advertisement’s being effective was that the advertisement must convey its message. This necessary condition was not then treated by the argument as if it were a sufficient condition. Instead, as described above, the Mistaken Reversal that actually occurred in the stimulus involved being humorous.

Answer choice (D): The word “effective” was not treated ambiguously in the stimulus. The word was used twice, and on each occasion was used in the sense of producing an intended result.

Sherry001

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Hello ,
This question upset me to a point I had to rip my test ! Extremely unfair. I am 100% convinced there are two correct answer and they are both the best answer choice. Ah ! Please set me straight - ! Why is C wrong here .?

1- if Humorous --> attract and hold people's attention.
2- Effective --> it must convey its message

A) this is true, the argument doesn't consider that other advertisements could also attract a persons attention. L

c) it treats a necessary condition of an advertisement being effective ( humours ones) as if it were sufficient .

Sherry
David Boyle
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Sherry001 wrote:Hello ,
This question upset me to a point I had to rip my test ! Extremely unfair. I am 100% convinced there are two correct answer and they are both the best answer choice. Ah ! Please set me straight - ! Why is C wrong here .?

1- if Humorous --> attract and hold people's attention.
2- Effective --> it must convey its message

A) this is true, the argument doesn't consider that other advertisements could also attract a persons attention. L

c) it treats a necessary condition of an advertisement being effective ( humours ones) as if it were sufficient .

Sherry

Hello Sherry,

Be careful about ripping up your test! The police might drop by (heh). More seriously,

humorous attract attention, hold attention long enough to convey message
Therefore:

Answer A is correct, since we can rephrase the above statements as,

B C, enough C to produce D
A D
Therefore:
A B

or, for the sake (or "shake", see below) of illustration:

good milkshake has sugar, and has enough sugar to reach the level of "sweet food"
successful restaurant offers sweet foods
successful restaurant good milkshake

But what if the restaurant could offer other foods besides milkshakes? What if there are other foods that have enough sugar to be sweet, say? Anyone ever hear of chocolate cakes? Etc. So maybe a good restaurant need not offer a good, or any, milkshake, even if it must offer at least one other sweet food.

So, answer A is right, that it falsely assumes humor is needed to attract/hold attention; maybe something else could. Just as another food could be sweet, not just milkshakes. Answer C is not true, in that humor is not a necessary condition in the first place. In fact, the stimulus doesn't treat "humorous" as a sufficient condition, in that "Humorous television advertisements are the only effective ones." is diagrammed as

, since "the only" is a sufficient indicator, not a necessary one.

Hope this helps,
David
elysia
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On this question, I was debating between answer A and E, and ultimately chose the incorrect answer E.
I'm still having a bit of trouble understanding why A is correct and E is incorrect.

I diagrammed

If Humourous Effective

If Humorous Attract people's attention AND message conveyed

Effective message conveyed

I thought E was correct because the last sentence in the premise addresses conveying the message as effective, but overlook attracting people's attention.

Please let me know where I went wrong...

Thank you!
PowerScore Staff

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Thanks for the question, elysia! Part of where you went wrong is with your diagram of the first sentence, which is the main conclusion of the argument - you got it backwards. See David's explanation in this thread - Humor is a Necessary condition for Effectiveness, not the other way around. The conclusion is:

Effective -> Humorous

As you can see from David's diagram, there is no way to prove a connection between humor and effectiveness - they cannot be linked in a conditional chain. That's why answer A is the best answer - it acknowledges that there is no certain link, and other things than humor might sufficient for catching attention and holding it long enough to convey a message.

Answer E focuses on the concept of "purpose", which is not a part of our argument. It's not about what the advertisers are trying to accomplish, but only about what actually works. Answer E is also not the best answer, because A so much more clearly expresses the mistake our author made.

Take another look at what David had to say, especially his delicious analogy, and see if that helps. Good luck!
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sekyiste
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Hello,

I thought the word 'only' introduced the necessary in the first sentence, so I diagrammed it as:

Humorous -> effective

Looking at explanations above I still don't understand why its the other way round?

Stephanie
Emily Haney-Caron
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Hi Stephanie,

Thanks for the question! You want to make sure you're thinking through the logic of it as you're identifying sufficient and necessary conditions. Sometimes it can help to turn a conditional statement that doesn't use if-then language into an if-then statement, while retaining the same meaning. So, based on the first sentence, which of these would be true?

Well, in this case, we know it has to be 2. Why? Because the sentence tells us humorous advertisements are the only ones that are effective. That means if it isn't a humorous advertisement, it can't be effective. Humorous is a necessary condition for an advertisement to be effective. So, when we're diagramming it, we'd need to put effective on the left and humorous on the right.

Take a look again at the sentence and see if you can make better sense of it now.
awilt
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I agree with Sherry, this question is beyond frustrating.

I've gone through all of the conditional rules that you spelled out above and I still do not understand where you are getting a mistaken reversal. Not sure if this is just going completely over my head or what.

I understand why A is correct, but not for the sake of it being a mistaken reversal. However, it came down to A or C and I chose C because I felt like A was a trap of sorts, like it may be a flaw but the author didn't necessarily have to consider it that there could be other effective things than humor.

Can you please explain why C is wrong? I feel like that will give me a better understanding than why A is right.

Thanks!
nicholaspavic
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Hi awilt,

Welcome to the Forum, and thanks for writing in! And I agree with you, this is a surprisingly tricky question given how early it appears in this LR section. But let's examine what answer Option (C) is really saying and see if that can help resolve your question about Answer Choice (A).

In order to get to get there, you have to really focus on what the last sentence of the stimulus is. "And, obviously, for an advertisement to be effective it must convey its message." The "must" here indicates the necessary which is why it is expressed as:

Considering and isolating that sentence alone, realize that it is a perfectly logical statement and that Dave's diagram is correct. There is actually nothing wrong with it at all! Therefore, Answer Option (C)'s language that focuses on the last sentence's necessary condition which was about message conveyance and NOT effectiveness (because effectiveness IS the sufficient per the diagram) is incorrect because effectiveness IS the sufficient in that sentence. Accordingly, the chain does NOT treat it as necessary.

Thanks for the great question and let us know if this helps.
harvoolio

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I have read all of the responses and can still not grasp why (c) is wrong. Maybe baby steps are necessary. Would you agree that the flaw is “Fallacy of the Single Solution”? In other words, the stimulus establishes certain conditions for an advertisement to be effective:

If an advertisement is effective it must convey its message (Necessary Condition).

Humor attracts and holds people’s attention long enough to convey a message (Sufficient Condition)