LSAT 91 - Section 2 - Question 08

This is a Flaw/Descriptive Weakening question.

The student claims that his paper was not graded in accordance with the professor’s stated criteria. That sounds like the conclusion. Okay, why not? What did the professor say the criteria would be? She said that she’d give As only to papers whose conclusions were supported by reliable statistical evidence. That’s a conditional. A → rse. His paper’s conclusion was supported by rse yet he got a B.

I don’t see what the problem is here. His paper met a necessary condition for getting an A. But he’s complaining that he only got a B? Oh, he must be confused about sufficient and necessary conditions. He thought rse → A. That’s why he thinks the professor should have given him an A.

This is the oldest mistake in the book. Correct Answer Choice (C) points it out. He takes a condition that is among the requirements (necessary) for a particular grade to be a condition that is enough to guarantee (sufficient) that grade.

Answer Choice (A) says the argument discusses the prof’s criteria as a distraction. But that’s descriptively inaccurate. The argument discusses the prof’s criteria in order to apply it to the case at hand, not to call attention away from anything.

Answer Choice (B) says the argument committed the descriptive premise to prescriptive conclusion flaw. That’s not what the argument does. The argument’s conclusion and premises are all descriptive.

Answer Choice (D) says the argument is based on the report of a biased participant in the controversy. Yes, this is descriptively accurate. The student is reporting the facts to us, facts about what the stated criteria was and facts about his paper. He is presumably biased. But so what? It’s not because of his bias that this argument is weak. His argument is weak because of a logical error.

Answer Choice (E) says the argument conflated the professor’s grading criteria with the objective criteria of a paper’s quality. What does this mean? (E) claims that there are two different criteria. There’s the professor’s criteria for grading (A only if rse). Then there’s the objective criteria for quality. What is it? (E) doesn’t say but presumably it’s different from the prof’s criteria. But there’s just one criteria. It’s not like the student argued that his paper met the prof’s criteria and therefore must be an objectively high-quality paper.