flaw reasoning

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flaw reasoning

by armaan700+ » Wed Feb 03, 2010 10:10 pm
It is illogical to infer a second and different effect from a cause which is known only by one particular effect. This is incorrect because the inferred effect must necessarily be produced by some different characteristic of the cause than is the observed effect, which already serves entirely to describe the cause.

Which one of the following arguments makes the same logical error as the one described by the author in the passage?

(A) An anonymous donor gave a thousand dollars to our historical society. I would guess that that individual also volunteers at the children's hospital.

(B) The radioactive material caused a genetic mutation, which, in turn, caused the birth defect. Therefore, the radioactive material caused the birth defect.

(C) The tiny, unseen atom is the source of immense power. It must be its highly complex structure that produces this power.

(D) The city orchestra received more funds from the local government this year than ever before. Clearly this administration is more civic-minded than previous ones.

(E) If I heat water, which is a liquid, it evaporates. If I heat hundreds of other liquids like water, they evaporate. Therefore, if I heat any liquid like water, it will evaporate.

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by komal » Wed Feb 03, 2010 10:36 pm
armaan700+ wrote:It is illogical to infer a second and different effect from a cause which is known only by one particular effect. This is incorrect because the inferred effect must necessarily be produced by some different characteristic of the cause than is the observed effect, which already serves entirely to describe the cause.

Which one of the following arguments makes the same logical error as the one described by the author in the passage?

According to the author :

Cause X ======> Effect First
Cause X ======> Effect Second (Illogical)

We have to find the same logical error. Lets see which answer choice does that :

(A) An anonymous donor gave a thousand dollars to our historical society. I would guess that that individual also volunteers at the children's hospital.
Correct : Anonymous Donor =====> Donates to Historical Society
Anonymous Donor =====> Volunteers at Chidren's Hospital (Illogical)


(B) The radioactive material caused a genetic mutation, which, in turn, caused the birth defect. Therefore, the radioactive material caused the birth defect.
Incorrect : Radioactive Material =====> Genetic Mutation
Genetic Mutation =====> Birth Defect
Hence Radioactive Material =====> Birth Defect

(C) The tiny, unseen atom is the source of immense power. It must be its highly complex structure that produces this power.
Incorrect : Atom is stated as the SOURCE. Not the CAUSE.... Clearly out of scope

(D) The city orchestra received more funds from the local government this year than ever before. Clearly this administration is more civic-minded than previous ones.
Incorrect : Civic-Minded Administration =====> More Funds

(E) If I heat water, which is a liquid, it evaporates. If I heat hundreds of other liquids like water, they evaporate. Therefore, if I heat any liquid like water, it will evaporate.
Incorrect : Heat Water (Liquid) =====> Evaporates
Heat Other Liquid Like Water =====> Evaporates
Hence Heat any liquid like water =====> Evaporates


Last edited by komal on Thu Feb 04, 2010 9:43 am, edited 2 times in total.

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by fibbonnaci » Wed Feb 03, 2010 10:43 pm
cause effect relationship.
Conclusion: Cause leads to only one effect. another effect cannot be inferred.

Lets look at the options now to see the compatibility:
(A) An anonymous donor gave a thousand dollars to our historical society. I would guess that that individual also volunteers at the children’s hospital. [ complete out of scope answer. there is no cause effect relationship in this answer choice. Eliminated!]

(B) The radioactive material caused a genetic mutation, which, in turn, caused the birth defect. Therefore, the radioactive material caused the birth defect. [ complete reverse of the concept in the stimulus. radioactive material causes birth effect and radioactive material causes genetic mutation. so we are attributing 2 different effects to a single cause. Eliminated!]

(C) The tiny, unseen atom is the source of immense power. It must be its highly complex structure that produces this power. [complex structure leads to immense power. there are no 2 effects described. single plain cause effect relationship is given. Eliminated!]

(D) The city orchestra received more funds from the local government this year than ever before. Clearly this administration is more civic-minded than previous ones. [ no cause effect relationship. Eliminated!]

(E) If I heat water, which is a liquid, it evaporates. If I heat hundreds of other liquids like water, they evaporate. Therefore, if I heat any liquid like water, it will evaporate. [ my answer. choice states that when you heat wate,r the effect is that it evaporates. similarly when i heat any other liquid, the effect is the same- it will evaporate. no the choice is in sync with the author's statement. no new effect can occur]

Hope this helps!

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by money9111 » Wed Feb 03, 2010 10:45 pm
I did not like this one at all! The use of infer reminds me of inferring and assumptions! not a fan ... btw I got it wrong too! lmao
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by vijay_venky » Thu Feb 04, 2010 5:00 am
I guess A.


The author of the argument is not happy if

Cause1-->effect1
Cause1-->effect2

and there is an explanation that he provides for this,

The effect1 characterizes cause, which can have only one characteristic(property).

Now we are up with a task to find out the option with the same logical error as stated by author, i.e,we are looking at an option in which an effect is inferred of a cause which has already had an effect,Now let us have a look at the options
A- reserve this for later
B- Here though we are inferring two effects from the same cause we are not attributing a second characteristic to it, because it is a transitive property, the characteristic that lead to both of the effects is the same.
C- Here we are inferring that complex structure of the atom is the cause of the immense power. (atom is just mentioned as the source of power, not the cause of it)
D- Same as above (civic-mindedness is the only cause of the funds)
E- Here because water and others evaporated any liquid will evaporate (this is less of a cause and effect scenario)

Now coming to A,
The first effect talks about the thousand dollars to a historical society.
The second effect talks about volunteering at a hospital.

This talks about different kinds of an effects from the same cause, so is my option.

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by joseph32 » Sun May 15, 2016 11:18 pm
In my opinion A is the most logical one.