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#27037
Complete Question Explanation

Assumption. The correct answer choice is (B)

The structure of the argument is as follows:
  • Premise: ..... There is only so much metal ore available.

    Subconclusion/ Premise: ..... Ultimately we must either do without or turn to renewable resources to take its place.

    Conclusion: ..... The current pattern of human consumption of resources, in which we rely on nonrenewable ..... ..... ..... ..... resources, for example metal ore, must eventually change.
At first glance the argument does not seem to have any holes. This would suggest a Defender answer is coming, and indeed that is the case.

Answer choice (A): The author does not need to assume this statement because the stimulus specifically indicates that “we must either do without or turn to renewable resources.” Since doing without is an option, the author is not assuming there are renewable replacements for all nonrenewable resources currently being consumed.

Answer choice (B): This is the correct answer choice. This answer defends the conclusion that the consumption pattern must change by indicating that it would not be possible to simply replace one nonrenewable resource with another nonrenewable resource. If this answer did not make sense at first glance, you should have noted the negative language and then negated the answer. Using the Assumption Negation Technique, the following would clearly attack the conclusion: “We can indefinitely replace exhausted nonrenewable resources with other nonrenewable resources.” If the nonrenewable resources can be indefinitely replaced, why do we need to change our consumption habits?

Answer choice (C): The author’s argument concerns changing current consumption habits. Although the author does suggest turning to renewable resources, this alone would represent a change. The author does not make a long-term assumption that renewable resources can never be depleted. When faced with the negation of the answer choice, the author would likely reply: “If that eventuality does occur, then perhaps we will have to do without. In the meantime, we still need to change our consumption habits.” As you can see, the negation has not undermined the author’s position, and so this answer is incorrect.

Answer choice (D): The author does not make statements or assumptions about actual consumption patterns in the near future, only statements regarding what must eventually occur.

Answer choice (E): This answer, when rephrased to eliminate the double negative, reads as “Ultimately we must have nonrenewable resources.” Because this answer hurts the argument, the answer is incorrect.
 tracy77
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#4369
"The current pattern of human consumption of resources,..."

For this question, is "do without renewable resources"(A) consistent with "the current pattern of human consumption of resources must eventually change"(B)? For me, I think if we can do without renewable resource, then it means we don't have to change the current resource consumption pattern which relies on nonrenewable resources. But if this is the case (since A and B are both stated in the question stem), then answer choice B seems not necessarily need to be the assumption?
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 Dave Killoran
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#4371
Hi Tracy,

I'm not sure I'm fully following the first sentence of your question, and it seems that you've rather broadly characterized what A and B mean, but even so, A and B aren't the same idea.

Regardless, I'd strongly disagree that "A and B are both stated in the question stem." Take a close look at what A says--it means that there's a renewable replacement for every nonrenewable resource. I don't see that stated in the stimulus.

On the other hand, B is definitely assumed in the argument because the author is saying that a change must occur, and that assumes that the nonrenewables will run out at some point.

Please let me know if that helps. Thanks!
 Lourdiana
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#59462
Good Evening - I'm having trouble understanding why A is not the correct answer. If we negated option A - it would say " There are not renewable resource replacements for all of the nonrenewable resources currently being consumed." Wouldn't that weaken the latter statement of the suggested change option ("....or turn to renewable resources to take its place.")
 Ben DiFabbio
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#59480
Lourdiana wrote:Good Evening - I'm having trouble understanding why A is not the correct answer. If we negated option A - it would say " There are not renewable resource replacements for all of the nonrenewable resources currently being consumed." Wouldn't that weaken the latter statement of the suggested change option ("....or turn to renewable resources to take its place.")
Hey Lourdiana,

I like that you're using the assumption negation technique to test these answer choices, but you have to be careful how you apply it. Your task in negating an answer choice is not to find something that would weaken the conclusion if it were not the case. Your task with the negation technique is to find something that would make the conclusion impossible to draw from the given premises if it were not the case.

When you negate answer choice A, as you outlined above, you get: "There are not renewable resource replacements for all of the nonrenewable resources currently being consumed."
The core of the argument is as follows: There is only such metal ore available. Conclusion: Ultimately we must either do without metal ore or turn to renewable resources to take its place.

If there were not renewable resource replacements, as in the negation of answer choice A, the conclusion of the argument could still follow because we could still do without.

The negation of answer choice A does not make it impossible for the argument to follow, so it is not a necessary assumption.

I hope this helps, and happy studying!

- Ben
 Lourdiana
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#59532
oh wow! ok this whole time I thought negating assumption questions was solely to weaken and not make the argument impossible. Thank you so much.
 Lily123
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#64734
Administrator wrote:
Answer choice (E): This answer, when rephrased to eliminate the double negative, reads as “Ultimately we must have nonrenewable resources.” Because this answer hurts the argument, the answer is incorrect.
Could you please explain why (E) hurts the argument?

My thought process was: If we can either do without OR turn to renewable resources to replace our consumption of nonrenewables, then what would be the reason we MUST change our consumption habits of nonrenewables?
[As opposed to letting them run out (and doing without them) OR replacing them with a renewable resource].

I thought E provided that reason by saying we MUST have nonrenewable resources. If E is negated, then it’s NOT necessary for us to have nonrenewable resources, in which case why would we need to change our consumption habits when we can do without them or turn to renewables?

Can you please help me understand where I’m going wrong with this? I’m really having a hard time seeing how the argument is hurt by this.
 Rachael Wilkenfeld
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#64769
Hi Lily,

For this one, try to think about what is required for the argument.

1. There is only so much metal ore available.
2. Therefore, ultimately we must do without or turn to non-renewable resources
3. Therefore the current pattern of consumption must change.

What's required for that? What do we NEED?

According to the argument, we don't need to do without. We don't need to turn to non-renewable resources. We need to do one OR the other.

Let's think of a parallel argument.

1. My salary is only so high.
2. Therefore, either we must cut back on spending, or get another job
3. Therefore, the current pattern of spending must change.

"I cannot do without a higher salary" would hurt the argument. It would mean that cutting back on spending or getting another job wouldn't be sufficient. And we wouldn't need to change our spending pattern at all, because we'd have more income.

Similarly, if "we cannot do without non-renewable resources" was a required assumption, the conclusion that we need to change our wouldn't follow. If we can't do without them, how would changing our pattern of use matter? Answer choice (E) basically challenges the truth of a premise (we either must do without or find renewable resources) because it says renewable resources aren't an option. That's adding something to the argument that isn't at all required.

What would be required? We need something that says our only choices are doing without or finding renewable resources. The way the argument is set up, the stimulus offers an either/or scenario. These are hard to support logically, unless they are logical opposites. "Either it will rain, or it won't rain" is easy to support. "Either it will rain or it will be sunny" is much harder to support. There's so much in between rain and sunny, and the statement assumes that NONE of the intermediate options can occur.

Similarly, here, the statement "either we must do without or we must find renewable resources" leaves a lot in the middle. There are tons of options between doing without and finding renewable resources. We assume ALL of them can't be the case. Answer choice (B) is just one of those assumptions, that we can't be considering switching infinitely between non-renewables.

Hope that helps!
Rachael
 Lily123
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#64797
Hi Rachael - Thank you for the quick & detailed response! Would you mind looking over my thought process? I just want to make sure I'm understanding this properly.

I was looking at the argument as a Supporter Necessary Assumption:
[p1] A is limited
[p2] Therefore, we must EITHER do without A OR turn to B
[c] Must change how A is consumed

Since P1 established that A is limited (i.e., it WILL eventually run out), the possibilities for A are binary: you either have it, or you don't. Based on that, the author tells us there are only 2 possible courses of action when A ultimately runs out:
- Option 1: Do without A
- Option 2: Turn to B
Then concludes that we must do something that is NEITHER of those options. Since the possibilities for A are binary, he's essentially saying, we need to make A last as long as possible. I saw this as a gap between P2 & the conclusion & was looking for a Supporter Assumption to close that gap.

Specifically, I was looking for something along the lines of:
- We cannot do without A (we can't let it run out, we need it, so we must change how A is consumed); OR
- When it runs out, we cannot turn to B (so we want to make it last as long as possible).
Rachael Wilkenfeld wrote: According to the argument, we don't need to do without. We don't need to turn to non-renewable resources. We need to do one OR the other.
...
Similarly, if "we cannot do without non-renewable resources" was a required assumption, the conclusion that we need to change our wouldn't follow. If we can't do without them, how would changing our pattern of use matter? Answer choice (E) basically challenges the truth of a premise (we either must do without or find renewable resources) because it says renewable resources aren't an option. That's adding something to the argument that isn't at all required.
So, what you're saying is, both of those answers would've been wrong because if one of our options is not possible, the argument necessitates we turn to the other (remaining) option:
- If we cannot do without A, then we must turn to B
- If we cannot turn to B, then we must do without A
In either case the conclusion (that we must do something that is neither A nor B) falls apart, which is why (E) hurts the argument. Is that correct?
Rachael Wilkenfeld wrote: What would be required? We need something that says our only choices are doing without or finding renewable resources. The way the argument is set up, the stimulus offers an either/or scenario. These are hard to support logically, unless they are logical opposites. "Either it will rain, or it won't rain" is easy to support. "Either it will rain or it will be sunny" is much harder to support. There's so much in between rain and sunny, and the statement assumes that NONE of the intermediate options can occur.
The way I'm understanding your explanation is:
There is no gap in the argument, instead the author has presented us with a potential false dilemma that we need to defend against.

If my understanding is correct, would you say it's more accurate to look at P2 as the conclusion? Because I still can't see how there ISN'T a gap between P2 & the conclusion & I'm trying to figure out how I can distinguish when there's an actual gap in the argument (Supporter assumption) vs. when the argument is sound (Defender assumption). How I typically approach Necessary Assumption questions is, if I see a gap, I try to close it; if I don't see a gap, then I move into defender mode.

Also, when I apply the assumption negation technique to (B) & (E) I get:

(B) We CAN indefinitely replace nonrenewables with other nonrenewables
(E) Ultimately we CAN do without nonrenewable resources

In EITHER case the conclusion (that we must change how nonrenewables are consumed) is not true.

Whereas, if the conclusion were: our ONLY options are to do without nonrenewables OR turn to renewables, then only (B) is required because negating (E) does nothing to the conclusion.

Thanks again!
 Zach Foreman
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#64816
Lily,
I would break the stimulus down a bit differently:

P1. The supply of any given non-renewable resources is finite.
A1 (P2). When a non-renewable resource is exhausted, the only alternatives are to do without non-renewable resources or turn to a renewable resource.
IC: Eventually, we will stop consuming non-renewables or consume renewable resources.
MC: Current pattern of consumption (using non-renewable resources) must change

You could actually stick in a couple other assumptions, but this is sufficient. You can see that in my opinion your premise 2 is simply an intermediate conclusion, because the main conclusion is just a restatement. Saying that "We are now doing A and we will eventually have to do B or C" is just a more detailed version of "We must eventually change what we are doing."

I think what makes this question difficult is that it has a hidden premise AKA assumption. And in fact, it is this assumption that is flawed. And it is very difficult to see the flaw if you don't make the assumption explicit. You can see that it is a false dichotomy. When you run out of a given resource, it is not true that the only alternatives are doing without or turning to renewable. We can substitute a different non-renewable.
In some ways, this question is a whole to part fallacy because it is trying to conflate running out of a particular non-renewable with running out of all the non-renewables.

So, I agree with you that there is a gap in the argument but it is not between the Intermediate Conclusion and the Main conclusion, but rather between the first premise and the Intermediate conclusion (since we need a minimum of two premises).

If we turn to the Assumption Negation Technique to E (we can do without nonrenewable resources), we see that the argument is not directly attacked because the author doesn't require nonrenewable as a feasible option. Perhaps we just do without, which would still be a change in the current consumption pattern.
In contrast, if we can jump from non-renewable to non-renewable (from iron ore to aluminum ore to magnesium, etc) forever, then the argument utterly fails and we can continue the same pattern of consuming non-renewables forever.

Basically, when using the ANT here you want to say "Which answer choice, when logically negated, makes it possible to continue the current pattern of consuming non-renewable resources. Saying we can do without nonrenewables in fact makes it more possible that we can change our current consumption patterns (because we can do without, right?) But, saying we can jump from one non-renewable to another forever, strengthens the idea that we can continue our current pattern of consumption which directly attacks the main conclusion.

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