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 Administrator
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#23012
Complete Question Explanation

Assumption. The correct answer choice is (E)

This argument concludes that the plant should be approved because those opposed to it presumably have a stake in its rejection:
  • Premise: All arguments against the plant have been presented by competing electricity producers;

    Premise/Sub conclusion: No good arguments have been offered against it;

    Main conclusion: The proposed plant should be approved.
This line of reasoning is not sound. Even if all the arguments against the plant are presented by competing electricity producers, this does not automatically mean that these arguments are bad. This is a flaw in the reasoning called "source argument" (or ad hominem attack). An argument can still be good even if its proponent has a vested interest in it. Second, even if no good arguments have been offered against the plant, their absence does not amount to an argument in its favor.

Because this is an Assumption question with a rather weak stimulus, you should look for a Defender Assumption that overcomes one of its weaknesses. For instance, it is essential to the author's conclusion that at least some of the arguments made by those who have a vested interest in the failure of the plant be bad. It is also necessary that the absence of a good argument against the plant amounts to a definitive argument in its favor.

Answer choice (A): This answer choice strengthens the argument by implying that the competing electricity producers have a particularly strong interest in seeing the proposal fail. However, the author's conclusion does not rely on the particular nature of such interests: she only needs to establish that they have a negative impact on the strength of the producers' arguments. Try the Assumption Negation technique: what if the producers do not stand to lose large amounts of money? They can still have a vested interest in seeing the project fail, and their arguments can still be defective. This answer choice is incorrect.

Answer choice (B): This answer is the Mistaken Reversal of what we need. Instead of establishing that the competing electricity producers' arguments against the proposal are defective, it presumes that they are. If the sufficient and necessary conditions in this answer choice had been reversed, this would have been a great Defender Assumption.


Answer choice (C): The net positive effect of the plant's approval on the energy industry's overall level of happiness might be an argument in favor of building the plant, but it is not essential to the author's conclusion. Even if disapproval pleased the competitors more than approval pleased he supplies, the argument would still hold.

Answer choice (D): Unfortunately, there is no evidence that any good arguments were presented for the proposal, which is why this is not an element essential to the author's conclusion.

Answer choice (E): This is the correct answer choice. By establishing that arguments made by those who have a vested interest in the proposal's failure are not good arguments, this answer choice provides a necessary premise to the author's conclusion. If these arguments were good, on the other hand, her conclusion would no longer be valid.
 Blueballoon5%
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#44855
Administrator wrote: Answer choice (B): This answer is the Mistaken Reversal of what we need. Instead of establishing that the competing electricity producers' arguments against the proposal are defective, it presumes that they are. If the sufficient and necessary conditions in this answer choice had been reversed, this would have been a great Defender Assumption.
Hello! I have a question about the explanation for answer choice B. I understand why answer choice B is wrong, but I am a little confused with the sentence in bold. The word "presume" means assumption, which is the necessary element in a conditional argument. The explanation above suggests that answer choice B put "the competing electricity producers' arguments against the proposal are defection" as the necessary condition. However, the answer choice B put that sentence in the sufficient condition.

For reference, answer choice B reads, "If a person's arguments against a proposal are defective, then that person has a vested interest in seeing that the proposal is not implemented."
 Adam Tyson
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#47725
Read "it presumes that they are" in this context as meaning "the answer choice treats the claim that the arguments are defective as a sufficient condition", rather than as a necessary one.

I'm not sure I agree with your analysis about the meaning of "presumed" here, Blueballoon5%. "Presumed" (or assumed, as you pointed out) refers to the relationship between the sufficient and necessary conditions, rather than indicating a condition itself. When presented with conditional claim IF X, THEN Y, the author presumes that X is sufficient for Y. Saying something is an assumption is not the same as saying it is a necessary condition, but only that it is some claim that has been accepted by the author without proof being offered to us, the readers.

If that has been tripping you up I hope this helps set you on a steadier path!
 kwcflynn
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#67182
Hi!

Considering that this weak stimulus (flawed reasoning) precedes an Assumption question, shouldn't the answer be Supporter Assumption rather than a Defender? I completely understand that classifying the type of Assumption correctly does not determine whether you will get the question right, but I just wanted to confirm.

THANK YOU

Kevin
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 KelseyWoods
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#67242
Hi Kevin!

Supporter Assumptions are typically present in arguments in which there is a clear missing link between the conclusion and the premises. The Supporter Assumption then fills in that gap and connects the conclusion to the premises. When you have a weak argument that is very vulnerable to attack, you are generally looking for a Defender Assumption that will eliminate those possible sources of attack.

That being said, there are not really hard and fast rules when it comes to defining an assumption as a Supporter or Defender. Think of the Supporter/Defender model as more of a way to conceptualize assumptions and the different roles they can play in arguments. Rather than needing to define each assumption as a Supporter or a Defender, it's more important to just be aware of the different ways to conceptualize them. Oftentimes, assumptions could be viewed as either Supporters or Defenders, depending on how you look at it. The important thing is to recognize that assumptions can play different roles and be prepared to find different types of assumptions in the answer choices.

Hope this helps!

Best,
Kelsey
 Nicholas Noyes
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#74098
Administrator wrote:Complete Question Explanation

Assumption. The correct answer choice is (E)

This argument concludes that the plant should be approved because those opposed to it presumably have a stake in its rejection:
  • Premise: All arguments against the plant have been presented by competing electricity producers;

    Premise/Sub conclusion: No good arguments have been offered against it;

    Main conclusion: The proposed plant should be approved.
This line of reasoning is not sound. Even if all the arguments against the plant are presented by competing electricity producers, this does not automatically mean that these arguments are bad. This is a flaw in the reasoning called "source argument" (or ad hominem attack). An argument can still be good even if its proponent has a vested interest in it. Second, even if no good arguments have been offered against the plant, their absence does not amount to an argument in its favor.

Because this is an Assumption question with a rather weak stimulus, you should look for a Defender Assumption that overcomes one of its weaknesses. For instance, it is essential to the author's conclusion that at least some of the arguments made by those who have a vested interest in the failure of the plant be bad. It is also necessary that the absence of a good argument against the plant amounts to a definitive argument in its favor.

Answer choice (A): This answer choice strengthens the argument by implying that the competing electricity producers have a particularly strong interest in seeing the proposal fail. However, the author's conclusion does not rely on the particular nature of such interests: she only needs to establish that they have a negative impact on the strength of the producers' arguments. Try the Assumption Negation technique: what if the producers do not stand to lose large amounts of money? They can still have a vested interest in seeing the project fail, and their arguments can still be defective. This answer choice is incorrect.

Answer choice (B): This answer is the Mistaken Reversal of what we need. Instead of establishing that the competing electricity producers' arguments against the proposal are defective, it presumes that they are. If the sufficient and necessary conditions in this answer choice had been reversed, this would have been a great Defender Assumption.


Answer choice (C): The net positive effect of the plant's approval on the energy industry's overall level of happiness might be an argument in favor of building the plant, but it is not essential to the author's conclusion. Even if disapproval pleased the competitors more than approval pleased he supplies, the argument would still hold.

Answer choice (D): Unfortunately, there is no evidence that any good arguments were presented for the proposal, which is why this is not an element essential to the author's conclusion.

Answer choice (E): This is the correct answer choice. By establishing that arguments made by those who have a vested interest in the proposal's failure are not good arguments, this answer choice provides a necessary premise to the author's conclusion. If these arguments were good, on the other hand, her conclusion would no longer be valid.
I answered B for this one. Can you please give an example of what " If the sufficient and necessary conditions in this answer choice had been reversed, this would have been a great Defender Assumption" would have looked like. I understand why E is correct now, but still confused as to why B is wrong.
 Robert Carroll
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#74127
Nicholas,

Answer choices (B) and (E) are largely reversals of each other, so to see what the correct order of answer choice (B) would have been, look at answer choice (E). Answer choice (E) is not quite the reverse because it is general about all arguments involving a proposal, whereas answer choice (B) is about only arguments against a proposal, but that's not an essential difference here.

It doesn't make sense for answer choice (B) to be giving us a conditional where the sufficient condition is the conclusion. The only way we could use such a conditional is for the sufficient condition to be true...but then the conclusion would already be proven. So the answer only helps if the conclusion is already true anyway, and thus provides no help to the argument.

Robert Carroll

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