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by gmatmachoman » Mon Jan 18, 2010 3:23 am
Even though the argument seems to be wierd, but its not really.

In simple terms(Conclusion) : According to the researcher, Kinesthesia is sufficient for maze- learning.
Now how can we weaken his thought process.

Step to be taken :Introduce a possibilty of some other reason that added to this Kinesthesia will serve the purpose for rats to do maze- learning.

In short A leads to Z.Now to weaken this say , Not only A , the presence of A+B leads to Z.

A:Kinesthesia
Z:maze- learning.
A+B:-Kinesthesia+Interaction with other sensory organs.

Now coming to E....It gives "some " information but not directly attacking the conclusion.

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by fibbonnaci » Mon Jan 18, 2010 10:33 am
This is a simple one but worded trickily.
"Of the senses other than sight, hearing and smell, only kinesthesia had not previously been shown to be irrelevant to maze learning"
This is actually a double negated sentence.
The sentence plainly worded means- sight, hearing, smell and kinesthesia have been shown to be relevant to maze learning.
From this the author concludes that only kinesthesia is sufficient. ie. he ignores the participation of other senses. So this is the flaw in his reasoning.

In E- the first part of the sentence- maze learning in rats depends on atleast 2 sources is correct
But the second part- one of which is kinesthesia but which of the remaining sources must be involved cannot be determined is wrong. The stimulus clearly mentions that sigh, hearing, smell are all relevant for maze learning.
This is a typical Half correct/Half wrong answer choice.

In B, it does not make the mistake of saying the sources cannot be determined.
Cannot be ruled out is different from cannot be determined.
In this context, cannot be ruled out implies cannot be ignored. ie. based on the data, the involvment of other senses cannot be ignored.
This clearly restates the premise. and hence is the correct answer.

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by vijay_venky » Thu Jan 28, 2010 3:58 am
I was a little confused when I saw the double-negated sentence. I reasoned it out this way,

let us say there are 6 senses in total

s1-sight,s2-hearing,s3-smell,s4-kinesthesia,s5,s6.


Of the senses other than sight, hearing and smell, only kinesthesia had not previously been shown to be irrelevant to maze learning

Now according to the statement, apart from s1,s2,s3 only s4 is not shown to be irrelevant.

so in effect s1,s2,s3,s4 are not shown to be irrelevant.

and in the experiment, there are groups of the rats which lack exactly one of (s1,s2,s3).

because all of the groups behaved in the same way, the researcher concluded that s4 is the sufficient thing.

apparently B and E are closer.

Now if we go for E, there should be at least two sources of non-irrelevant sensory stimulations common to all the groups of the rats. But they contain only one common non-irrelevant sensory stimulation and that is s4. So it is not possible.

But B says there should be there is a probability that there should be atleast one sense along with the s4, which if true attacks the conclusion.

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by komal » Fri Jan 29, 2010 8:07 am
A: INCORRECT : The argument is not about differences in maze-learning proficiency. It is about relevance of senses in maze-learning.

B. CORRECT : Attacks the conclusion by providing other possible cause (kinesthesia + atleast one other sense) for the stated effect (maze-learning)

C. INCORRECT : Strengthens the argument by showing that kinethesia plays more imp. part in maze learning in the absence of other senses.

D. INCORRECT : Out of scope. The issue is not about nonkinesthetic stimulation.

E. INCORRECT : This answer choice is very tempting unless when looked at closely. It is a typical Shell-Game answer choice in which an issue is raised in the argument and a very SIMILAR idea appears in the answer choice, but the idea is changed just enough to be incorrect.
Argument : atleast two sensory stimulation (kinesthesia + one other sense)
Answer choice : atleast two sensory stimulation (kinesthesia + other source cannot be determined)

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by bhumika.k.shah » Fri Jan 29, 2010 11:03 am
simply brilliant! :-)
fibbonnaci wrote:This is a simple one but worded trickily.
"Of the senses other than sight, hearing and smell, only kinesthesia had not previously been shown to be irrelevant to maze learning"
This is actually a double negated sentence.
The sentence plainly worded means- sight, hearing, smell and kinesthesia have been shown to be relevant to maze learning.
From this the author concludes that only kinesthesia is sufficient. ie. he ignores the participation of other senses. So this is the flaw in his reasoning.