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editor

Expert replies
by gmatmachoman » Sun Dec 06, 2009 4:11 am
To the editor:

In 1960, an astronomer proposed a mathematical model for determining whether extraterrestrial life exists. It was based on the assumptions that life as we know it could exist only on a planet and that many stars are, like our Sun, orbited by planets, On the basis that there are nine planets in our solar system and one of them has life as we know it, the astronomer predicted that there are as many as one million extraterrestrial civilizations across all solar systems. Yet astronomers to date have not detected even one planet outside our solar system. This indicates that the astronomer's model is wrong, and life as we know it exists only on the plant Earth.

Clay Moltz

Which one of the following, if accepted by Clay Moltz would require him to reconsider his conclusion?

(A) Forms of life other than life as we know it exist on other planets.
(B) There are many stars that are not orbited by planets.
(C) Detecting planets outside our solar system requires more sophisticated instruments than are currently available.
(D) The soundness of the conclusion reached by applying a mathematical model depends on the soundness of the assumptions on which the model is based.
(E) Due to sheer distances and expanses of space involved, any extraterrestrial civilization would have great difficulty communicating with ours.

IMO D
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Source: — Critical Reasoning |

by godspeed » Sun Dec 06, 2009 4:52 am
IMO its C
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by nakul_anand » Sun Dec 06, 2009 5:23 am
IMO C
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by gmatv09 » Sun Dec 06, 2009 8:52 am
Agree with others .... C
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by Testluv » Sun Dec 06, 2009 7:02 pm
Yep, the answer is definitely choice C here.

What is his main reason for concluding that life exists only on Earth? It is the second-to-last sentence:

"Yet astronomers to date have not detected even one planet outside our solar system."

But choice C tells us that the reason we have to date failed to detect other planets might not be because there aren't any other planets; rather it might be because our equipment sucks. Then, Mr. Moltz would have to reconsider arriving at his hasty conclusion so fast!
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by okigbo » Sun Dec 06, 2009 8:54 pm
testluv,

can u pls explain why d is wrong? thanks
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by Testluv » Sun Dec 06, 2009 9:36 pm
I think the reason choice D is tempting is that it sounds sensible and also because it is within the scope of the argument (mathematical model). Yes, choice D sounds very sensible. But Mr. Moltz likely already accepts that the soundness of a mathematical model's conclusion depends on the soundness of the assumptions on which the model is based; nothing in his argument denies this.

The math model itself is not based on any questionable assumptions. Instead, Mr. Moltz' attempted refutation of the math model assumes that the equipment is sensitive enough to detect planets outside of the solar system.
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by joseph32 » Sun May 15, 2016 10:35 pm
In my opinion C is the most logical one.
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