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I get that you want an answer that says negative evidence is rarely conclusive and I was stuck between B and C which both involved failure of Newton's Law but was unsure as to what role the initial or ultimate part played. I ended up choosing C which is incorrect. What is the reasoning to get B?
 Emily Haney-Caron
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Hi Amy,

Good question. For this question, the key is to not take the last sentence of Passage A in isolation, but rather to consider the context (the three sentences before it). That can help clarify that we're not just looking for an answer where negative evidence is not conclusive, but where one of the premises is false when a prediction fails. That leads us to B over C. Does that help?
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Why not answer (D)? That seems like an example of negative evidence -- i.e., the fact that Vulcan was never found was a reason to doubt Newton's laws (but not sufficient to immediately disprove them).
 Francis O'Rourke
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This question is asking us to determine which example shows negative evidence leading to multiple possible conclusions.

After scientists saw Uranus's orbit seemed to go against Newtonian predictions, they had two possible conclusions: Newton's laws are incorrect, or there was an error in auxiliary assumptions. This is a clear example of "more than one possible explanation."

The non existence of Vulcan led some scientists to doubt Newton and ultimately led to only one conclusion: Newton was wrong. We are not told that there were multiple possible conclusions drawn from the non-discovery of Vulcan.
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Why is (E) wrong? After mulling it over, I was thinking maybe because Einstein's theory actually does reject old theories and is one of the instances where negative evidence is conclusive, but I don't know. Even if that were the case, that could still be the example of the rare instance where negative evidence is conclusive?

Thank you!

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