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astronomical system

Expert replies
by gmat009 » Sat Nov 22, 2008 2:14 pm
Copernicus's astronomical system is superior to Ptolemy's and was so at the time it was proposed, even though at that time all observational evidence was equally consistent with both theories. Ptolemy believed that the stars revolved around the earth at great speeds. This struck Copernicus as unlikely, he correctly thought that a simpler theory is that the earth rotates on its axis.

The argument most closely conforms to which one of the following principles?

(A) Simplicity should be the sole deciding factor in choosing among competing scientific theories
(B) If one theory is likely to be true, and another competing theory is likely to be false, then the one likely to be true is the superior of the two.
(C) If all observational evidence is consistent with two competing theories, the one that is more intuitively true is the more practical theory to adopt.
(D) Other things being equal the more complex of two competing theories is the inferior theory
(E) Other things being equal, the simpler of two competing theories is the more scientifically important theory
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Source: — Critical Reasoning |

by mals24 » Sat Nov 22, 2008 2:38 pm
Im not too sure about this but I would go for B.

A: Simplicity should be the sole deciding factor in choosing among competing scientific theories

Now we don't know if simplicity is the 'sole deciding factor'. This option is too extreme. INCORRECT.

C: If all observational evidence is consistent with two competing theories, the one that is more intuitively true is the more practical theory to adopt.

Practicality of the theories is not discussed. Also whether the Copernicus' theory was intuitively true and hence is more practical to adopt is not discussed.

D: Other things being equal the more complex of two competing theories is the inferior theory

Well this option can give B a tough competition. Now we know that Copernicus' theory was superior to that of Ptolemy, and also that Copernicus' theory was simpler, but we don't know if Ptolemy's theory was complex. I mean it could also be a simple theory, but comparatively Copernicus' theory was simpler.

E: Other things being equal, the simpler of two competing theories is the more scientifically important theory

The importance of the theories is not discussed.

Whats the OA of this tricky question?
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by gmat009 » Sat Nov 22, 2008 2:39 pm
Even I picked B but answer is not B.
I am waiting for some more discussions before posting OA
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Re: astronomical system

by iamcste » Sat Nov 22, 2008 3:09 pm
gmat009 wrote:Copernicus's astronomical system is superior to Ptolemy's and was so at the time it was proposed, even though at that time all observational evidence was equally consistent with both theories. Ptolemy believed that the stars revolved around the earth at great speeds. This struck Copernicus as unlikely, he correctly thought that a simpler theory is that the earth rotates on its axis.

The argument most closely conforms to which one of the following principles?

IMO D

(A) Simplicity should be the sole deciding factor in choosing among competing scientific theories
(B) If one theory is likely to be true, and another competing theory is likely to be false, then the one likely to be true is the superior of the two.
(C) If all observational evidence is consistent with two competing theories, the one that is more intuitively true is the more practical theory to adopt.
(D) Other things being equal the more complex of two competing theories is the inferior theory


This struck Copernicus as unlikely, he correctly thought that a simpler theory is that the earth rotates on its axis


(E) Other things being equal, the simpler of two competing theories is the more scientifically important theory
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Re: astronomical system

by parallel_chase » Sat Nov 22, 2008 3:18 pm
gmat009 wrote:Copernicus's astronomical system is superior to Ptolemy's and was so at the time it was proposed, even though at that time all observational evidence was equally consistent with both theories. Ptolemy believed that the stars revolved around the earth at great speeds. This struck Copernicus as unlikely, he correctly thought that a simpler theory is that the earth rotates on its axis.

(D) Other things being equal the more complex of two competing theories is the inferior theory
This is a must be true question [it seems like]

Everything stated in D, perfectly matches with the Argument without any assumptions.

OA?
No rest for the Wicked....
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by mals24 » Sat Nov 22, 2008 3:20 pm
But how do we know that Ptolemy's theory was complex??? It could be simple as well.

A is simpler than B. Means B is either less simpler than A or B is complex.
This struck Copernicus as unlikely, he correctly thought that a simpler theory is that the earth rotates on its axis.
So we can say that the theory that is likely to be true is more superior to the theory that is likely to be false.

I know B is not the right answer, but I still feel its a better option than D.
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by mals24 » Sat Nov 22, 2008 3:27 pm
Other things being equal the more complex of two competing theories is the inferior theory
Gosh I missed this point. Well now even D fits in properly. I feel both B and D are fine.

Today is not a good day, this is the 2nd question I'm solving where I'm getting 2 options right!!! :?
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by niraj_a » Sat Nov 22, 2008 3:43 pm
D for me, between B and D, this is because the stem doesn't talk anywhere about which theory is 'likely' to be true.
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by Jatinder » Sat Nov 22, 2008 8:31 pm
B is not supported.

No claim for the theory being false.
Keep flying
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Re: astronomical system

by muzali » Sat Nov 22, 2008 11:24 pm
gmat009 wrote:Copernicus's astronomical system is superior to Ptolemy's and was so at the time it was proposed, even though at that time all observational evidence was equally consistent with both theories. Ptolemy believed that the stars revolved around the earth at great speeds. This struck Copernicus as unlikely, he correctly thought that a simpler theory is that the earth rotates on its axis.

The argument most closely conforms to which one of the following principles?

(A) Simplicity should be the sole deciding factor in choosing among competing scientific theories
(B) If one theory is likely to be true, and another competing theory is likely to be false, then the one likely to be true is the superior of the two.
(C) If all observational evidence is consistent with two competing theories, the one that is more intuitively true is the more practical theory to adopt.
(D) Other things being equal the more complex of two competing theories is the inferior theory
(E) Other things being equal, the simpler of two competing theories is the more scientifically important theory
It is stated in the argument that
1. All observational evidence is consistent with both theories.
2. Stars revolving around the earth at great speeds struck Copernicus as unlikely
& 3. that he correctly thought that a simpler theory....
Therefore, the key point to note is all things being equal, simplicity is not , but a lack of complexity is the deciding factor

So, the only choice that satisfies these conditions is (D) Other things being equal the more complex of two competing theories is the inferior theory
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by mals24 » Sun Nov 23, 2008 1:14 am
he correctly thought that a simpler theory is that the earth rotates on its axis.
I don't think the fault in B is whether one theory is true and the other false. Its clearly mentioned in the sentence above that Copernicus correctly thought.

I understood why D is the answer. Can someone explain why option B is wrong?

Sorry guys but Im still confused :(
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by gmatnvarun » Sun Nov 23, 2008 1:25 am
my choice is D...other close choice is E but since it has the phrase 'more scientifically important ',I wont choose it
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by Spring2009 » Sun Nov 23, 2008 3:43 am
I agree with D.
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by nervesofsteel » Mon Nov 24, 2008 12:39 am
I don't know why B is correct

Question is talking about two theories equally acceptable .. it never said first theory was wrong......

So B should be incorrect

In D ... it is said that complex of the two theories should be inferior..
It can be treated as the same as the reason given for choosing second theory over first by author...
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by jeevan.Gk » Tue Nov 25, 2008 8:52 am
Its D.. But Keyword strategy says its C !!!! .. HJope its not..
OA pls??
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