What does the Question Stem tell us?
"depends on assuming" = Necessary Assumption
Break down the Stimulus:
What's this argument trying to prove? That rocks chosen for Japanese gardens should vary widely in appearance. How do we know? The word "hence" introduces our conclusion . "Hence" also tells us that the statement which comes before it is evidence supporting the statement that follows it. This clues us in to the fact that the fist line, that Japanese Gardens should display harmony with nature, is the first premise. The second premise can be tricky to spot because it is contained in the same sentence as the conclusion, but if you note the keyword "since," you can see that the last half of the final sentence, which tells us that rocks found in nature also vary widely in appearance, is offered as evidence supporting the first half.
Any prephrase?
Looking for a new concept in the conclusion is a great way to spot the gap in Assumption questions, but here, both concepts are addressed: 1 in each premise. Because this argument is conditional, we could think of splitting the conclusion and building inward with the premises to figure out where the gap is. That would look like this:
Rocks for J.Gardens --> Display Harmony w. Nature (____________) Rocks in Nature --> Vary Widely in Appearance.
Looking at it this way, we can see that there is a big hole in the argument, denoted by the parentheses: this argument assumes that to be in harmony with nature the rocks must mimic nature.
Correct answer:
B
Answer choice analysis:
A) "Every" is a red flag in Necessary Assumption questions. They seldom have such an extreme degree. What's more, the other key values besides harmony with nature are out of scope.
B) Corrrect! A match for our prephrase. Note the difference in degree between this answer choice, which uses "helps" rather than something more extreme, such as "requires," and answer choice A.
C) This is a classic Necessary Assumption trap answer. In order for it to be true that a criteria for choosing rocks for Japanese Gardens is harmony with nature, we don't need to assume that the only criteria for choosing rocks for Japanese Gardens is harmony with nature. Note also that this has an extreme degree, and is a premise booster, just upping the degree of premise #1.
D) This is a very tempting answer choice because it expresses one possible prephrase: that this argument equivocates (LSAT word!) being in harmony with nature and being as it appears in nature. But answer choice (D) displays a subtle difference: it uses "natural" rather than "as it appears in nature," and that's problematic, because "natural" doesn't have a concrete enough meaning. If you've ever seen "All Natural American Cheese" you know this to be true!
E) In order to conclude that the rocks must be varied, we don't need to assume that each element must be varied.
Takeaway/Pattern: 1. If there's no new concept in the conclusion of an Assumption Question, split the conclusion and build inward to spot the gap, and beware extreme degree in Necessary Assumption answer choices!
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