#14 - Marine biologists had hypothesized that lobsters kept

[Administrator]

Complete Question Explanation

Assumption. The correct answer choice is (E)

This is another causal Assumption question, where the author concludes that lobsters kept together in cages for extended periods do not eat one another in response to hunger. This is based on the fact that there are instances of lobsters kept together for extended periods that did not eat one another. Of course, the assumption in this argument is that the lobsters that did not eat one another were, in fact, hungry. If the lobsters were not hungry this argument would be severely weakened because any behavior that the lobsters displayed would not be in response to hunger.

Answer choice (A): This argument is only about lobsters caught in traps, so this answer is unrelated to the stimulus.

Answer choice (B): The longest amount of time that lobsters have been trapped together is not necessary for this argument. The argument is only about whether lobsters eat one another in response to hunger.

Answer choice (C): The fact that it is uncommon for a large number of lobsters to be trapped together is not important. All that matters is whether or not hunger is the cause behind them eating one another.

Answer choice (D): Information about other marine creatures is not relevant to an argument about lobsters.

Answer choice (E): This is the correct answer choice. Essentially answer choice (E) is saying that the lobsters observed not eating one another were hungry while trapped together.

[Johnclem]

Hi,
For this question I had trouble negating answer choices. In class we were taught to drop the "not" or add not when there isn't a conditional relationship ( for which we would negate by denying the necessary condition ).
So when I negate answer choice A I see it as destroying the argument . So how is this not the answer ?


1- marine biologists had hypnotized lobsters kept in traps would eat one another.
2- but lobsters that were in traps revealed lobsters sharing without eating one another.
C: the marine biologists hypothesis is therefore wrong :

A) lobsters not caught in traps have been observed eating one another.
Negated : lobsters caught in traps have been observed eating one another.


Thanks
John

[Adam Tyson]

In my experience, John, the negation technique is at least as much an art as a science. The goal is to take the answer choice that you are testing and make it untrue. Sometimes it's all about adding or deleting a "not", but often it's about re-phrasing the whole answer, and sometimes, like here, deleting a "not" doesn't give you any kind of a negation but rather gives you something completely irrelevant.

Take this sentence: "People not from around here support Senator Jones' proposed legislation." If all we do is remove "not" we get "People from here support Senator Jones' legislation." Does that make the first statement untrue? Nope, because it's talking about the wrong group of people - people from around here instead of the ones who are not from around here. To negate this sentence, which already has a "not" in it, you have to add another not - "People not from around here don't support Senator Jones' legislation."

The same issue comes up in the answer you are testing - we want to negate the idea that those free-roaming lobsters have been seen eating one another. The proper negation, then, is something like "lobsters not caught in traps have not been observed eating one another." That new statement denies the truth of the answer choice, and is therefore the proper negation.

Now, the next step is to ask yourself whether that negation wrecks the argument, and it does not. Neither does your version of the negation, for that matter, because the argument isn't just about whether or not lobsters eat one another, but about whether they do so in response to hunger. In other words, do hungry lobsters turn cannibal? The correct answer, when negated, tells us that the particular trapped lobsters that the author based his conclusion on were not hungry, so they tell us nothing about what hungry lobsters do. That negation destroys his argument, proving that the answer choice must be an assumption of the argument.

When testing negated answer choices, be less mechanical and more holistic and intuitive in your approach. Does the negated answer make the answer choice false? Is it the equivalent of saying "that's not true, that didn't happen!"? If not, then you don't have the right negation. That's a good test to see if you negated correctly. Another way to negate an answer (although a bit clumsy and confusing at times) is to insert at the beginning of the answer choice "It is not true that". For example, "It is not true that lobsters not caught in traps have been observed eating one another."

Try this new approach to negations - I hope it works some magic for you!

[Nikki Siclunov]

John,

Let me add my 2c to Adam's excellent response above. When you negate complex statements, always negate the verb independent (main) clause of the statement. Instead, you negated the verb subordinate/dependent clause. The dependent clause does not bear the weight of the negation, and should be left intact.

Take a look at this blog post for further clarification of this idea:

Negating Compound and Conditional Statements

Let me know if you have any questions.

Thanks!

[jbrown1104]

Hello PS,

I was wondering if you could clarify the reasoning as to why answer choice (E) is correct. I was between (D) and (E) and chose (D) because I thought the answer choice when negated directly attacked the marine biologists assumptions that lobsters "eat one another in response to hunger". I now understand through the explanation that the conclusion only explicitly spoke about lobsters, and because this is an Assumption question, extraneous information (i.e. other marine animals) is unnecessary. However, I am still having trouble understanding how (E) is correct, perhaps it is the wording of the answer choice? Please help me understand how I can check the answer with the Assumption Negation Technique.

Thanks!
~JB

[Dave Killoran]

Hi JB,

Thanks for the question! This has always been one of my favorite Assumption questions, and it's a good one to study at length and make sure you understand.

So, we know that the conclusion of this argument is that lobsters kept in traps do not eat one another in response to hunger. In other words, that hunger isn't the cause. For the author to make this conclusion based on the example of the right lobsters means that the author was thinking the lobsters were hungry, and that even though that cause was present, they still didn't eat each other (the effect). That's what (E) is saying.

Now, when you negate (E), you can see how it works against the argument. The negation is: "Any food that the eight lobsters in the trap might have obtained was not enough to ward off hunger." If that's the case, it means that the lobsters were never hungry, ad thus this example doesn't serve to prove that hunger isn't a cause. Therefore, the author can't claim with certianty that the marine biologist's hypothesis is wrong. Since the negation hurts the argument, this is the correct answer.

Please let me know if that helps. Thanks!

[jbrown1104]

Hi Dave! Thanks so much for responding.

I think I get it! By the author assuming they were hungry he is able to defend his entire argument that lobsters do not eat each other in response to hunger. The ONLY way the author's argument stands is if the 8 lobsters were hungry because if they weren't hungry, then author cannot cannot claim that the marine biologists were in correct because then they would be comparing apples and oranges essentially in a sense, am I correct?

Thank you for explaining! Is there some trick to be used to attack assumption questions of this nature in the future? Perhaps I am so stuck on trying to see the trick that the test makers are trying to pull I neglect to see that the simplest answer choices can be correct (and for assumption questions, you want simplicity).

Thanks,
~JB

[Adam Tyson]

Other than prephrasing what they author left out of his argument, JB, and then trying to match that to your answer choices, is to then test any contender answers (if you have more than one) with the Assumption Negation Technique as we've described here. Since the Assumption is something the author MUST believe to be true, then if it turns out NOT to be true his argument will fall apart, every time.

Give that a try and see how it works. Good luck!

[Nicholas Noyes]

I just want to clarify,

The marine biologist says that hunger is the reason for lobster self-consumption

The argument against the marine biologists' claim is, that HUNGER IS NOT the reason why lobsters consume one another. Using the example that the eight lobsters were hungry for two months (in a trap) and they did not eat one another (even though they were hungry).

So ANSWER E is saying that the lobsters were hungry and they did not consume one another, therefore, saying that the marine biologists' hypothesis is wrong, because the lobsters in the trap were hungry and did not consume one another.

By negating ANSWER E, it destroys the argument used against the marine biologist, that hunger is not the cause of lobster self-consumption. The argument says that the eight lobsters in the trap were hungry, BUT the negation of ANSWER E says the eight lobsters were NOT hungry in the trap because they attained enough food. And since the eight were not hungry you cant use that example as an argument against the marine biologist's hypothesis.

I know that sounds confusing but, I have been trying to think this question through. Please let me know if I am on the right track or if I am mistaken.

-Nick