Q7 - Library policy: For a book to be removed from circulat

[ohthatpatrick]

Question Type:
Strengthen (application of principle)

Stimulus Breakdown:
RULE: If removed, then badly damaged and not checked out for 2+ years (3+ years, if it's written by local author or locally significant)
APPLICATION: Paper Flowers shouldn't be removed.

Answer Anticipation:
We need to contrapose the rule so that it's written in the form of "If X or Y or Z ... , then should not remove book".

If a book isn't badly damaged, it shouldn't be removed.
If it's been checked out in the last two years, it shouldn't be removed.
Or if it's a locally written/important book and it's been checked out in the last three years, it shouldn't be removed.

So we basically need to hear that Paper Flowers is not badly damaged, has been checked out in the last two, or [is locally written/important + has been checked out in the last three].

Correct Answer:
B

Answer Choice Analysis:
(A) This is the opposite of what we'd want.

(B) YES, this will work.

(C) Unclear whether this works, until we'd know whether PF is locally written/important.

(D) Unclear on its own, until we'd know whether PF has been checked out in the last three years.

(E) Unclear on its own, until we'd know whether PF has been checked out in the last three years.

Takeaway/Pattern: When LSAT presents a rule that says "for X to be justified, Y and Z have to be true", they are usually testing us on the contrapositive: if either Y or Z does not hold, then X does not. The correct answer uses the contrapositive of the first sentence.

The second sentence is a complex rule. It's using the form "only if", but it's making it harder to apply a mechanical shortcut because instead of saying "Removed only if ____ ", it's saying "only removed if _____ ". Overall, we should hear in these rules a presumption in favor of keeping these books. None of these rules say that something SHOULD be removed. Rather, they stipulate conditions under which books CANNOT be removed. Diagramming this might be harder than just conversationally pulling out the criteria that would trigger the CANNOT be removed protection.

#officialexplanation

[LenaC504]

Will you clarify how to negate "-checked out for 2+ years" to "checked out for less than 2 years?" Wouldn't the negation instead be "checked out for 2+ years," meaning that we would need the book to have been checked out 2 years or more ago in order for that book to have been checked out of the library for at least 2 years?

Thank you!

[smiller]

This is a case where we have to be careful when abbreviating or paraphrasing parts of the argument. The condition that we're trying to negate is that the book "must not have been checked out for over two years." In other words, this is requiring that more than two years have passed since the book was last checked out. So Patrick's negation, "it has been checked out in the last two years," or "the book has been checked out within the last two years," is correct.

(To negate this in a really precise way we could say, "the book was not checked out two years ago, or within the last two years," but we can evaluate answers without splitting that hair.)

I think we also need to be careful in how we interpret the word "for" in the phrase, "must not have been checked out for over two years." The context of the stimulus leads me to think this condition is about when the book was checked out, not the length of time that someone kept it. However, I can totally see how someone might interpret "checked out for over two years" to mean that someone checked the book out and didn't bring it back until two years later.