Hi slj,
Thanks for the question, and welcome to the Forum!
Let's start by examining what is, and what is not, "stated" by Jorge. He makes three statements that are outlined in the explanation for this question in the LRB:
1. Ruth was an infant in the 60s (premise)
2. Rock music of the 60s was created by/for people then in their teens and twenties (premise)
3. Ruth won't be able to write well about the rock music of the 60s (conclusion)
Note that at no point does he ever say the reason Ruth won't be able to write well about it is "because you were not in your teens or early twenties in the 60s, and thus not someone who created rock music or for whom rock music was created." That belief is implied, but not explicit.
Thus that is the "unstated" assumption that Jorge is making: those not a part of the rock music scene at the time (creating it or intended audience) cannot write well about it.
And it's that unstated assumption that the age difference is
why she won't be able to write well about 60s rock, that implied connection between facts (how old Ruth was and who 60s rock was by/for) and main belief (she can't write well about 60s rock), that Ruth's analogy is intended to dispute: there is a clear disconnect between living writers and ancient Romans, yet these writers can still write well about ancient Roman culture.
So be careful here. It may seem quite obvious what Jorge's reasoning is, but that's only because we as readers are inclined to make the same connection between premises and conclusion as Jorge does. That's not the same thing as stating it explicitly though, and for that reason the answer choice is totally acceptable calling it "an unstated assumption."
I hope that helps!
Jon Denning
PowerScore Test Preparation
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