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#16 - From the observation that each member of a group could

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Complete Question Explanation

Parallel Flaw. The correct answer choice is (C)

The argument proceeds by making a conclusion and then giving an illustrative example. However, you are not asked to describe the argument. The question stem indicates that you should concentrate on the fallacy described. You should focus on finding a similar flaw.

The argument states that even though each member of a group could possess a characteristic, that does not mean all the members could possess the characteristic at the same time.

Even though the wording of the first sentence might be hard to understand, the situational example is not. Clearly, only one person wins the tennis tournament, even though initially any one of the players had the possibility of winning it. If you had a hard time with the abstraction in the first sentence, you should just try to pick a similar example.

In general, the idea is that some events preclude others.

Answer choice (A): It is easiest to eliminate this choice by comparison to the example. In a tennis tournament, there is something in the very nature of winning that prevents everyone from winning at the same time. There is a slight fallacy in Lincoln's quote, if you assume that you cannot fool yourself, but since it might be possible to fool yourself, his statements might be sound. In other words, there is nothing necessary about fooling everyone else that prevents you from fooling yourself as well.

Answer choice (B): This response contains perfectly sound reasoning, and thus cannot illustrate a flaw. Furthermore, this choice does not claim that each candidate possesses a quality, only that each seems to.

Answer choice (C): This is the correct answer choice. Since "many" very probably means more than three, it is fallacious to claim that all of the nominees can be appointed. Furthermore, this is very similar to the example offered in the stimulus, because just like winning a tournament, filling an appointment eliminates possibilities for other candidates. Even if you did not like the use of "many," this response is more justified than other responses. Furthermore, the actual definition of "many" is "consisting of a large indefinite number" when the group has not been specifically numerically limited, and the definition of "several" is "more than two or three, but not many," which implies that three is less than many, and you are expected to be familiar with the definitional implications of words, and make appropriate judgments.

Answer choice (D): This is horrible reasoning (the probability is actually about 3%, not 50%), but is based on a misunderstanding of probability rather than failing to realize that one event precludes another.

Answer choice (E): This reasoning is somewhat flawed, but only because it overlooks other methods of determining whether life exists on other planets. Furthermore, this reasoning is not based on failing to realize that a possibility has been ruled out, but rather on attempting to devise a method of elimination.
alee
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Hi guys,

Keep up the great work!

I have a question about Prep Test 14, Sect IV, Q.16. I understood the stimulus as:
1. It is fallacious to conclude that all of a group's members possess a characteristic based on the observation that *each individual* member *could* possess that characteristic.
2. Example: concluding that all players entering into a tournament could *together* win the whole tournament based on the observation that *each of them individually* could win the tournament

I chose narrowed it down to (c) and (d), but am having trouble seeing why (d) is wrong:
'If a fair coin is tossed 5 times, then on each toss the chance of heads is half. Therefore the chance of heads being the result on all 5 tosses is also a half'.

Would it be accurate to say that (d) is wrong because there isn't a 'group' being referred to per se (unless you count the 5 tosses as a 'group', but since each toss is identical, without having differentiated characteristics this doesn't seem to 'fit' with the initial tennis players example).

Thanks
Steve Stein
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Interesting question--I'd say the coin toss example is different in a few ways, as you've already alluded to. It's not really a group, as you pointed out, and it deals with a statistical error unlike the flaw found in the stimulus. Also, with parallel reasoning questions, it can be very helpful to consider the language of the conclusion. Take a look at the three conclusions under consideration for a very clear distinction:

Stimulus: ..... it is therefore a possibility
Answer C ..... Therefore it is possible
Answer D ..... Therefore the chance of all flips landing heads up is, specifically, 1/2.

Let me know whether this is helpful--thanks!

~Steve
Steve Stein
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Adam Tyson
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Alee,

I don't have that test in front of me (which month and year is that?), but based on what you've told us here, I'd say you're looking at the difference between an error of composition (what's true of the parts is not necessarily true of the whole) and a plain old math error (if the chance of a coin coming up heads is 1/2, then having it do so 5 times in a row is 1/2 x 1/2 x 1/2 x 1/2 x 1/2, or 1/32). It's not so much about the "group" having a characteristic in common with the parts - there really isn't a group, just a single event repeating itself.

Hope that helps!

Adam M. Tyson
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Adam M. Tyson
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alee
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Thanks Steve,

I found that helpful... In particular- referring to the language of the stimulus and 'matching it' to the question for parallel reasoning questions (that's a technique that almost always works for me, but didn't occur to me this time!)
Johnclem
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Hello,
Can someone please explain what's the flaw in answer choice A ? When I read it I didn't think it was flawed . But the above explanation says otherwise. :-? :-?

Thanks
John
Nikki Siclunov
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Hi John,

There is no reason to suspect that there is a flaw in answer choice (A). There is, but that's beside the point. This answer choice simply doesn't parallel the Error of Division we observe in the stimulus. You should be looking for an answer choice where a characteristic of each member of a given class is presumed to apply to the entire class. This is not what's happening in answer choice (A): all we know is that everyone can be fooled sometimes, and that some people can be fooled all the time. Of course, that doesn't necessarily prove that we can't fool everyone all the time... maybe we can? If some apples are red, maybe all apples are red. We just can't prove that they are, but for reasons completely unrelated to the Error of Division we're looking to parallel.

Hope this helps!

Thanks,
Nikki Siclunov
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Blueballoon5%
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Administrator wrote:Answer choice (A): It is easiest to eliminate this choice by comparison to the example. In a tennis tournament, there is something in the very nature of winning that prevents everyone from winning at the same time. There is a slight fallacy in Lincoln's quote, if you assume that you cannot fool yourself, but since it might be possible to fool yourself, his statements might be sound. In other words, there is nothing necessary about fooling everyone else that prevents you from fooling yourself as well.


Hello! I am slightly confused with the discussion here on fooling yourself. The answer choice doesn't seem to imply/assume anything about fooling yourself. The scope seems to be more narrow on "you fooling something/everyone." Could you clarify what you meant by this explanation?

Thanks!
Adam Tyson
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If you can fool all of the people, blueballoon, that means you can also fool yourself, because you yourself are, in fact, one of "all the people." That's the only reason we brought that up, just to illustrate a problem with the argument in A. It's not why the answer is wrong, but just an internal problem with one of the premises.

I am going to diverge slightly from my colleagues on a key issue about answer A here, and that is to say that one of the easiest ways to reject it is because it is NOT, in fact, an argument. The author (Abraham Lincoln may or may not have said it) didn't try to prove anything. There are no premises and no conclusions, just statements of fact (or opinion). That's not an argument, and so it cannot commit a flaw of argumentation.

Don't worry about the "fooling yourself" aspect of the explanation, as that was just an illustration of the problem with one of the claims (it seems unlikely that you can fool all of the people some of the time, because that would mean you can at least sometimes fool yourself). That's got nothing to do with why the answer is not parallel to the stimulus. Sorry if that caused some confusion! We didn't mean to fool you!
Adam M. Tyson
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