Question Type:
Necessary Assumption
Stimulus Breakdown:
When these two conditions are met, the result is great art. When they aren't, the result is not great art. (The combination of those two statements is a biconditional!) Therefore, great art is rare.
Answer Anticipation:
"Rare" is a huge new term in the conclusion; the frequency/rarity of these conditions being met isn't discussed in the premises (the LSAT is playing off of your assumption that they're rare). The correct answer will mention that at least one of these two conditions (skill and creativity), or their combination, is rare.
Correct Answer:
(B)
Answer Choice Analysis:
(A) Half scope. In fact, all artists could have skill, as long as it was rare to also have creativity. Since we have two conditions here, we can't definitively state which one has to be rare to make this argument work.
(B) Bingo. Creativity and skill are linked inextricably to great art. The author relies on that combination being rare to reach his conclusion. The negation here: Creativity and skill are usually combined when making art. That kills the argument.
(C) Premise booster (more or less). The argument already states this in the first sentence. It's not an exact match - this is about having the conditions, whereas the premise is about using them - but that's what makes it a premise booster.
(D) Half scope. Same issue as in (A). This argument can still work even if all artists have a high level of creativity, as long as skill is rare.
(E) Tricky answer! It suggests that, even when an artist has these two conditions, they will still rarely produce great art. However, if every artist is making great art (however rare it is individually), it could very well be the case that the world ends up with a lot of great art. This answer is about the rarity of a single person creating great art; the argument is about the overall amount of great art. If you picked this answer, you committed a part vs. whole flaw!
Takeaway/Pattern: When two conditions are given for a rule, Necessary Assumption questions will try to trick you with answers that deal with only one of them. This neglects the possibility that the other conditions is always met. Just because, between me and Michael Phelps, we've won 26 gold medals doesn't mean that I've won any!
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