#16 - Global, Must Be True

[Dave Killoran]

Complete Question Explanation
(The complete setup for this game can be found here: lsat/viewtopic.php?t=11359)

The correct answer choice is (E)

From the setup discussion, we know that W is always on the second or third shelf. Hence, answer choice (E) is correct.

[sotor26]

Hello,

I am having a little trouble understanding why E is correct. Although I know that Woolf is not on the first shelf, I don't understand why A can not be true. A linguistic monograph has to be in the first shelf in all situations, correct (P or S).

[Lucas Moreau]

Hello, sotor26,

I'm glad you chose this question - I've taught this question in classes many times and know it pretty well by now!

For Question 16: It is not necessarily true that only a linguistic monograph can be on the first shelf. The first shelf could also contain the Vonnegut novel. Since no two of V, P, and S can be on the same shelf as each other (combination of the second and third rules), one of each of them must be on each shelf - which means the first shelf must be P, S, or V. Does that make sense?



Hope that helps,
Lucas Moreau

[sotor26]

Thank you so much! It makes sense now! I can't believe I overlooked that.

[adlindsey]

Before I got to this question, I was looking at the set-ups for this game and I was wondering why W can't be on the 1st shelf?

[Emily Haney-Caron]

Hi adlindsey,

Great question! This is a tricky one, and requires an inference combining rules 2 and 3. We know that P and S can't be on the same shelf from rule 2, and we know that V can't be with P and V can't be with S from rule 3. The inference here is that V, P, and S all must be on different shelves, meaning that one of those three has to be on the first shelf. Since the first shelf has only one slot, that means no book BUT those three can be on the first shelf.

Hope that helps!

[adlindsey]

Thank you. I had a feeling it had to do with a combination of rules, but I couldn't see it.