I don't get the CR here. The stimulus clearly non-sequiturs from the non-existence of one thing to the invalidity of a belief in something else. The only answer that fits that structure is (E), however the CR is (A), which doesn't contain belief in its conclusion.
I understand that the stimulus also uses the existence of the thing in the necessary condition to non-sequitur into belief about the sufficient condition, and this pattern of necessary/sufficient is mirrored in the CR. However, A completely changes the nature of the conclusion from the stimulus while E retains it.
I don't see how you'd distinguish between these in some kind of objective fashion? The other 3 choices are clearly bad.
PT 52, section 1, problem 16 Forum
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bee's vision
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Re: PT 52, section 1, problem 16
A-"a belief in extraterrestrials is false as well" is logically equivalent to "there are no extraterrestrials"...so "there are no unicorns either" is the same as a "a belief in unicorns is false" (if there are no unicorns how could a belief in them be true?)
E--the stimulus argument is structured as anyone who believes in ET-->believes in UFO, but there are no UFOs so there are no ETs or believe's in A-->believes in B, ~B so ~A. The answer choice is structured as believes in A-->B, ~A so no ~B which is still flawed but reversed from the stim. If you switch unicorn and centaurs in the second sentence it would be correct.
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E--the stimulus argument is structured as anyone who believes in ET-->believes in UFO, but there are no UFOs so there are no ETs or believe's in A-->believes in B, ~B so ~A. The answer choice is structured as believes in A-->B, ~A so no ~B which is still flawed but reversed from the stim. If you switch unicorn and centaurs in the second sentence it would be correct.
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androstan
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Re: PT 52, section 1, problem 16
I see.bee's vision wrote:A-"a belief in extraterrestrials is false as well" is logically equivalent to "there are no extraterrestrials"...so "there are no unicorns either" is the same as a "a belief in unicorns is false" (if there are no unicorns how could a belief in them be true?)
E--the stimulus argument is structured as anyone who believes in ET-->believes in UFO, but there are no UFOs so there are no ETs or believe's in A-->believes in B, ~B so ~A. The answer choice is structured as believes in A-->B, ~A so no ~B which is still flawed but reversed from the stim. If you switch unicorn and centaurs in the second sentence it would be correct.
