- Wed Nov 16, 2016 9:12 pm
#30626
The key to the credited response here, 15, is the word "possible".
The stimulus gives us a conditional chain, as you noted:
Share -> Delay -> Suffering
The author concludes that not sharing is wrong, and we want a principle that helps that argument along.
Answer C talks about the possibility of alleviating suffering - if you share you might be able to reduce suffering. You are absolutely correct that we cannot prove that a contrapositive is a true statement based solely on the original claim. However, we don't need to prove it's true (that sharing will reduce suffering), we only need to show that it's possible. Mistaken Negations and Mistaken Reversals, while not provable, are nonetheless possible.
Imagine this conditional claim - it you parachute out of an airplane you will land on the ground. Now, if I say that you are on the ground, I can't prove that you jumped from a plane, right? But is it possible that you did? Sure it is! If I was to say that you did not jump out of a plane - is it possible that you are not on the ground? Of course! I can't prove it, but it's possible that you are in a plane, or a helicopter, or a hang-glider, or you've been plucked up by an alien spacecraft and flown to the nearest asteroid belt for further study.
Since C says that it would be wrong to do withhold information that could be helpful, that's the answer we are looking for. It strengthens the argument by telling us that refusing to share is wrong, since sharing at least makes it possible to alleviate some suffering.
Be on the lookout for similar questions involving conditional reasoning and Could Be True questions. Remember that Mistaken Negations and Mistaken Reversals can be true, even though we can't prove them.
Good luck!
Adam M. Tyson
PowerScore LSAT, GRE, ACT and SAT Instructor
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