Self-study
Although tales of wonder and the fantastic are integral to all world literatures, only recently has the fantasy genre had a commercial resurgence in North America. ██████ ███ ████ ██ ██████ █████ ██ ███████████████ █████ ███████ ███ ██████ ████ ████ ████ █ ██ ██ ███████ ██ █████ █████████████ ██████ ██ ███ ████ █████ ███ ██████ ██ █████████ ███████ ██ ███████ █████ ███ █████████ █████████ ████ ███████████ ███ ████ ███ █████████ █████ ██ ███████ █████ ███████ ███ ██████ ███ ██ ██████ ██ ███ █████████ █████████ █████████ █████ ███ █████ ██ ████ ██████████
Argument Breakdown: Correlation to Causation
The stimulus tells us about some booksellers, who conclude that a recent increase in fantasy book sales was caused by increased positive reviews. Why do they think so? Because the increase in sales occurred over the same time period as the increase in positive reviews.
The booksellers' argument shows a classic mix-up between correlation and causation. The factual premises only establish a correlation between book sales and positive reviews, but the booksellers' conclusion assumes that one caused the other. This gives us some space to attack—or defend—the argument.
Strategy: Weaken/Strengthen
The booksellers' argument falls within phenomenon-hypothesis reasoning: they observe a phenomenon (the correlation between book sales and reviews) and form a hypothesis to explain it (reviews caused book sales to rise).
To weaken this kind of logic, we can propose an alternative hypothesis: for example, maybe the increase in sales actually caused the increase in reviews, or a third factor caused both. We can also find evidence that's incompatible with the hypothesis, to suggest something else is going on.
To strengthen, we would do the exact opposite. Eliminating a competing hypothesis would strengthen, as would finding compatible evidence that aligns with the booksellers' conclusion. We could also find a causal mechanism that explains how exactly reviews increased book sales.
18.
Which one of the following, ██ █████ ████ ████████ ████████ ███ ██████████████ ███████████ ██ ███ ██████ ██ █████ ██ ███████████████ █████ ███ ███████
a
Many experts report ████ ██ ███████ ███ ███████ █████ ██ ████ ██████ ███ ████████ ████ ███ ████ ██ ██████
(A) tries to suggest an alternative explanation for the rise in fantasy book sales: maybe their popularity is growing because they're at a lower reading level. But this doesn't work: we don't know the reading level of fantasy books, and even if we did, an alternative explanation would only weaken, not strengthen.
b
Because life during ███ ████ ██ █████ ███ ██████ ███████ ███ ██████████ ████ ███████ ████ ████ ██ ██████ ███ █████ ███████ ████ ███████ ███████ █████ █████████
(B) offers an alternative explanation for the increased popularity of fantasy books: it's not because of reviews, but rather due to the difficulty of life. But this is a weakening answer, not the strengthener we're looking for.
c
Some fantasy publishers ████ █████████ ██ ███ ██████████ ██ ███████ █████ ██ █████████████ ███████ ██████
In other words, popularity begets popularity. But (C) has nothing to do with reviews, so it doesn't strengthen the case for positive reviews having caused the recent fantasy resurgence.
d
Because few readers ██ ███████ ██████ ████ ██████ ███████ ████████ ██ █████ ███ ███ █████ ██████████ ██ ███████ ███████ ███████ ██ ███████████ ████████ ████████ ████████████ ██ █████ ████████
Like (B), (D) proposes an alternative explanation for why fantasy books became more popular. But any alternative explanation is a weakener, whereas we need a strengthener.
e
After fantasy fiction █████ ██ ██ █████████ ████████ ██ █████████ ███████ ██ █████ ████ ████ ██████ █████ ██ ██████ ███████ █████ ██ ████████ ███████ ███ ███████
(E) gives us a causal mechanism for how positive reviews could have increased fantasy book sales. Book buyers thought fantasy was just for kids, but these reviews opened up a whole new market of adult readers. By further explaining the causal link, (E) strengthens the argument.