#23 - Naturalist: A species can survive a change in

[alee]

Hi!

This question is about Preptest 53, Section III, Question 23 (the naturalist's argument). I interpreted the argument to have the following logical structure (contrapositive reasoning):
Prem: A->B
Conclusion ~B->~A

i.e. the argument seems to be:
Prem: species survives a change -> change not too rapid
Conclusion: change too rapid -> species does not survive a change

In order to justify option D, we can see that it follows an identical logical structure
Prem: People not fearing changes -> knowing what the change will bring
Conc: Not knowing what the change will bring -> People fearing changes

Is that rationale sufficient and comprehensive to justify the correct option and eliminate the others?

Thanks for all the help!

[Steve Stein]

On that one, the naturalist says that a species can survive change if the change is not too rapid. So, if the change is not too rapid, a species can survive:

Change not too rapid species can survive change

Thus, since a threat to the woodland species does exist, it must come not from the mere existence of change, but rather from how that change is being brought about (too quickly).

Since the stimulus is followed by a Parallel Reasoning question stem, the correct answer choice must follow a similar line of reasoning. Answer choice D does so:

If people are informed, then they do not fear change:

People informed not fear change

Thus, since fear among the people does exist, it must come not from the mere existence of change, but rather from how that change is being brought about (without informing).

Let me know whether that makes sense--thanks!

~Steve

[alee]

Hi Steve,

Thanks for the help. Do you mean to say that in my original specification of the problem, i put the sufficient and necessary conditions the wrong way around? here is what I originally had below.

Prem: species survives a change -> change not too rapid

You suggested:

Change not too rapid -> Species CAN survive a change

Do you think that my original formulation is still a correct way of interpreting the question, since it says that if a species *did in fact* survive then it must be the case that the change was not too rapid.

In contrast, whereas my formulation refers to whether or not the species did or did not survive the change, yours refers to the *capacity* of the species to survive or not.

However are both equally valid intepretations or is yours more correct? Thanks!

[Steve Stein]

Thanks for your response--I'd say that your breakdown works as well--interesting question--thanks again!

~Steve

[taylorballou]

Hi,

I chose answer choice C for this question, and I was hoping someone could explain why. I originally thought it was the best choice because I interpreted the reasoning as "it's not just studying that helps you succeed, but how thoroughly you do it," which I thought was similar to the stimulus argument "it's not just the changes we are making that threaten the animals, but how fast we do it." I'm not sure if this answer choice is wrong because it juxtaposes two different aspects of studying, time versus thoroughness, whereas the stimulus considers how only the speed of change threatens animals.

Thanks,

Taylor

[Kristina Moen]

Hi Taylor,

This is a great opportunity to use the Double the Conclusion test. Pay attention to the language.

In the stimulus, we have a threat to wildlife species and two possible reasons for it: "the fact that we are cutting down tree" and "the rate at which we are doing so." The author's conclusion is that the threat stems from the latter.

In answer choice (C), we have two possible reasons for doing well in school: "how much time a student puts into studying" and "how thoroughly the student studies." The author's conclusion is that the latter is "most" important for doing well in school.

Contrast that with answer choice (D). We have two possible reasons for employees to feel fear: "company’s undergoing change" and "our failing to inform them of what the changes entail." The author's conclusion is that the fear stems from the latter. This is a match!

[MikeRov25]

So I picked A for this, I thought that the speed factor played a role in the correct answer choice...obviously this is wrong. I think I see why D is but input from you guys would be great.

Premises of the stim is: Not to rapid --> Species can survive
Conclusion: Threats --> Not from cutting down, but from the rate at which we do so.

Answer D: the premises match for conditional reasoning purposes,
And the conclusions match because, they are saying it is not factor x but factor y that is causing the threat.

Am I thinking about this right, or am I way off base here?

[Adam Tyson]

One thing to keep in mind, MikeRov25, is that in Parallel Reasoning questions, the details and topic of the stimulus rarely matter. The fact that the argument was taking into account speed doesn't dictate that speed needs to also be in the correct answer. The authors of the test probably put that in answer A just to trap you there!

The problem with A is that it doesn't follow the underlying structure of the stimulus - "X is okay, but be careful about Y; the problem in this case, then, is not X, but rather Y." Look for that structure, and you'll see it's absent from answer A. Where is the X factor that is being set aside as being no problem?

Answer D has that X factor - change - and the Y factor - the unknown - as well. It tells us that X isn't a problem, but Y is, just like our stimulus. That "Test of Abstraction" can help you avoid answers that have attractive elements, like the speed in answer A, and focus instead on the real necessities, like the underlying structure of the argument.

Keep at it, you'll get there!