#14 - Unlike stars, planets do not generate light, but only

[Administrator]

Complete Question Explanation

Flaw in the Reasoning. The correct answer choice is (E).

Answer choice (A):

Answer choice (B):

Answer choice (C):

Answer choice (D):

Answer choice (E): This is the correct answer choice.

This explanation is still in progress. Please post any questions below!

[merkvslsat]

Hey, powerscore or someone else,
On my review, I remember this one looked weird. Is E correct because it points out the sort of false dichotomy in that it assumes, a non planet generates light, and a planet reflects light? just trying to understand every Q of the new material before October. Thanks in advance!

[Robot1212]

Hey, powerscore or someone else,
On my review, I remember this one looked weird. Is E correct because it points out the sort of false dichotomy in that it assumes, a non planet generates light, and a planet reflects light? just trying to understand every Q of the new material before October. Thanks in advance!

Alright - got this one right so ill try to help out.

Premise: Planet -> /generate light, reflect
Premise: Star -> Generate light
Premise: There are other celestial object
Conclusion: other celestial object generate light

Flaw: Maybe no celestial objects in the galaxy generate light. Like, maybe stars are the only things to generate light. It's like saying.

John doesnt have cake.
Parker has cake.
There are other people at this party.
Therefore, other people at this party have cake.

Nah. Maybe Parker is a dweeb and only brought cake for himself.

A) conclusion is about things that generate light not reflect it
B) maybe of that minute percentage, none of them produce light
C) ok. we are only talking about celestial objects in the galaxy - so this doesnt point out a vulnerability
D) this is fine. but we are talking about the ability of celestial objects to generate light
E) this is what we predicted
It is worded a little funny but its basically saying that other celestial objects, other than planets, might not also produce light. In the cake example, it would be like saying, maybe John is not the only one at the party who doesnt have cake... this leaves open the possibility that everyone else at the party doesnt have cake too.

Hope this helps!

[Adam Tyson]

That's a great analysis, Robot1212, and I love the use of the analogy!

Another way to look at this argument is to see the conditional reasoning flaw. As Robot explained, one of the premises is that planets do not generate light, or:

Planet Generate Light

The conclusion is based on a Mistaken Negation of that relationship. The author is saying that anything that is NOT a planet DOES generate light, or:

Planet Generate Light

But this fails to consider that stars might be the only things that generate light. Not being a planet isn't sufficient to prove anything! Maybe all those other things out there just reflect light, or are dark, rather than generating light. That's what answer E is saying, albeit in a confusing way.

One way to think about that answer is to ask what would happen to the argument if it was true. If there were objects out there other than planets that do not generate light, then there is no reason to believe that there are any such objects that DO generate light! Our author would have to hang their head and say "oops, my bad, I should have thought of that." None of the other answers has that effect on the argument, and so none of them are flaws in the reasoning.

[Katherinthesky]

Is the question stem a Flaw or Weaken?

I understand that stems with "most vulnerable to criticism" usually refer to Flaw, but the addition of "fails to consider the possibility that..." makes me think this is Weaken.

Thanks in advance!

[Robert Carroll]

Katherinthesky,

This is a Flaw. Each of those phrases is associated with Flaw questions, and their combination doesn't do anything to change that judgment.

Robert Carroll

[g_lawyered]

Hi P.S.,
In this question, I ID the rogue terms between the premise (planets) and conclusion (generate light) to form assumption. I was able to eliminate answers A & B. But kept C and E as contenders. Even though C doesn't mention planets, I thought it was a contender because that's what the argument was assuming- that there could be other celestial object that generate light (that's not a planet in this galaxy). Can someone please explain why answer choice C is incorrect?
And what about answer choice E makes it the correct answer?
I read Adam's explanation above, however; I didn't draw out conditional reasoning for the arguments so I didn't see how answer E follows that.
Thanks in advance!

[Robert Carroll]

GGIBA003,

First, "generate light" is not a rogue term at all - it's mentioned both in the premises and conclusion.

Because the conclusion is about "celestial objects in this galaxy", I don't see how the argument is making any assumption about other objects outside this galaxy at all. Thus, answer choice (C) is wrong.

Even if you didn't draw out conditionals originally, because Adam's explanation is an excellent one that makes sense of this otherwise confusing stimulus, reading it should clear up any problems. Can you tell me what about Adam's post is not clear to you?

Robert Carroll

[g_lawyered]

Hi Robert,
I see where I went wrong thinking the assumption was about rogue terms when instead it was about something the author overlooked. I don't understand why makes answer choice E the correct answer because I interpreted it, as in a way, rephrasing what the last sentence states. The conclusion mentions "celestial objects" and the answer choice mentions "planets". Are we suppose to treat these as different objects?
How can the flaw of the argument be something the author actually stated instead of something the author incorrectly inferred? I hope my question makes sense...

Thanks in advance!

[Adam Tyson]

Answer E does not restate anything the author said, GGIBA003, and it is something the author failed to consider. The author assumed that planets are the only celestial objects that do not generate light, and E says the opposite of that - they are NOT the only ones that do not generate light.

Also, "planet" and "celestial object" are not the same thing, in the same way that "milk" and "dairy product" are not the same thing. Milk is just one of many dairy products, and planets are just one kind of celestial object.