#22- The folktale that claims that a rattlesnake’s age can

[satipod]

Hi! I am tad confused about a question from the December 1999 Test.

#22: Could anyone explain to me why A is not a better answer than E. I can see the reasoning behind E, but it makes total sense to me that the argument relies on the fact that the rattlesnake molts only once a year since we're discussing age here. Although, since that's the incorrect answer, I can also see test makers somewhat intentionally making that answer choice A to catch those who pre phrased that answer. Anyway, I could definitely use some clarification there.

Many thanks in advance!

[Steve Stein]

Thanks for your question.

On that one, the author says that if a rattlesnake's rattle didn't break, it could be used to determine the snakes age, based on the number of moltings.

The question asks for an assumption required by the author's argument. The author concludes that we could tell a snake's age by its rattle (or number of moltings), but that doesn't mean that they need to happen once per year, as provided by answer choice A. For example, what if they molted (and correspondingly increased their rattles) every six months? The rattle could still be used to determine their age. So, this choice is not an assumption that the author requires.

And what about answer choice E? That says basically that food supply doesn't affect the number of moltings. The author must assume this, otherwise there would be no way to use the number of moltings to determine age (since there would be more or less moltings depending on how much food was around).

That answer choice A is a tricky one--that's probabaly why they presented it first!

Let me know whether that clears that one up--thanks!

~Steve

[satipod]

Thank you, it definitely does. Looking into it that way makes a lot of sense and I agree that the "once a year" answer was probably presented first for those in a rush to finish off the section.

[helenliu]

I was unable to identify this question whether as a Justify or Assumption question. If this is a Justify question, why A is wrong?

Thank you very much!

[Steve Stein]

Hi,

That is an assumption question, because it asks for the assumption that is required by the argument.

Had it been a Justify question, (A) would have been a winner.

I hope that's helpful!

~Steve

[helenliu]

Thank you so much!

[powerguy]

After reading this one, my mind went for a toss. Why is C) wrong? After all, as in E), C) also indicates that when they are young, they molt more frequently than when they are old ---establishing the frequency of molting or the connection between molting and age. also, I would like to understand why is E) correct. I guess it's because E) establishes the periodicity of molting? Not sure.


-Tripp

[Nikki Siclunov]

(C) weakens the argument: if the snakes molted more frequently when young than when old, that would throw a wrench in our ability to figure out exactly how old they are (unless we know how the frequency of molting changes as they age). The proper assumption should have been "young rattlesnakes molt as often as old rattlesnakes" (or something along those lines).

(E) is a classic Defender Assumption. Try negating it - you'll see the argument falls apart immediately. The logical opposite of E presents an alternative reason why the folktale claims should be rejected - having nothing to do with the brittleness of the rattle.

[lawschoolforme]

I also was torn with this question - I now understand why E works well as a Defender Assumption, but A still makes sense to me. Why is A wrong? Is it because the author doesn't have to be committed to this statement in order for the conclusion to be properly drawn?

[Lucas Moreau]

Hello, LSFM,

You've got it half right, with your analysis of A. You do in fact need a high level of commitment, as you say, for a correct Assumption answer choice. An Assumption answer choice is always a necessary condition. The reasoning being that the correct answer choice must be assumed in order for the argument not to fall to pieces.

For this specific question, A is not absolutely mandatory for the argument to still proceed. Not specifically A, anyway. The argument would proceed properly if rattlesnakes molted, for instance, every month. Or twice a year. The important thing to the argument is that they molt at regular periods. It doesn't matter so much exactly how long the period is, as long as it's the same every time.

Hope that helps,
Lucas Moreau
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