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 est15
  • Posts: 94
  • Joined: Aug 28, 2013
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#16554
My diagramming for this one was:

violates rule of society (rule promotes general welfare) :arrow: wrong
required by a rule of society (rule promotes general welfare) :arrow: right

Is it true that the answer choices with "not wrong" or "not right" would definitely be incorrect because the contrapositives of the two diagrams above would leave "not wrong" and "not right" on the left hand side? If that's true, could you explain why that's the case?

Thank you.
 Robert Carroll
PowerScore Staff
  • PowerScore Staff
  • Posts: 1787
  • Joined: Dec 06, 2013
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#16566
est,

Excellent diagram!

In these sorts of Must Be True questions with Principles, the only thing you can conclude is a necessary condition of one of those conditionals, OR the negation of a sufficient condition. This is so because you can only USE a sufficient condition to get to a necessary condition, and the contrapositive just uses the negation of a necessary condition to get to the negation of a sufficient condition. In short, you're right that an answer choice that concludes an action is "not wrong" cannot follow from the ethicist's principle, because that principle only tells us that an action under certain conditions is right, and an action under certain other conditions is wrong. Attempting to move from the negation of a sufficient condition to the negation of an necessary condition involves a Mistaken Negation.

As we can't say for sure that "wrong" and "not-right" (or "not-wrong" and "right") are equivalent here, we can't ever conclude anything but "right" or "wrong" from these conditionals. This can be a helpful way to eliminate wrong answer choices.

For instance, in answer choice (A), Amelia has violated a rule and it is concluded that she did not do something wrong. Nothing in the principle allows me to conclude that something is not wrong, so this can't follow from the principle.

Robert Carroll

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