Logical Reasoning

PT119 · S2 · Q20 Professor Donnelly’s exams are always

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Professor Donnelly’s exams are always more difficult than Professor Curtis’s exams.

Conclusion

The question about dinosaurs must be difficult.

Evidence

Professor Donnelly’s exams are always more difficult than Professor Curtis’s. + The question about dinosaurs was on Professor Donnelly’s

Evaluation

This question stem crazily asks for both the flaws? So I guess we need to find more than one.

One flaw here is Part vs. Whole. Just because Professor Donnelly’s exam is difficult wouldn't mean that each question on it has to be difficult. LSAT is a difficult exam, but there are still some easy questions on it.

The harder to spot flaw is the Relative vs. Absolute move. Knowing that one exam is more difficult than another exam does not show that either exam is difficult.

A 3rd grade math test is more difficult than a 1st grad math test, but neither one is difficult in an absolute sense.

Goal

We need an answer that has both a Whole to Part flaw and a Relative to Absolute flaw.

20.

Which one of the following exhibits both of the logical flaws exhibited in the argument above?

Lewis is a better baker
Weak Evidence Match
The relationship of cake to baker isn't a great Part vs. Whole match. And the conclusion is strangely comparing this cake to most of Stockman's cakes.
11% picked this
Correct
Porter’s new book of poetry
Why this is right
This has the Whole to Part move, because it reasons that since the whole book is good, the poem must be good. And it has the Relative to Absolute move, because it goes from saying that something is better to saying that something is good.
Skill tested: Parallel Flaw · how this choice captures the argument's function is the move to repeat next time.
74% picked this
Professor Whitburn is teaching English
Trap
No Part vs. Whole Absolute to Relative Topic Trap The evidence and the conclusion are both about a "whole", the overall amount of reading assigned in Professor W's class. There is a move from Absolute to Relative, which is a reverse of the original. We go from "a lot of reading" (absolute) to "more reading" (relative). Beware answer choices that seem to recycle the topic of the original argument.
2% picked this
Shield’s first novel has a
No Part vs. Whole
This does have a Relative to Absolute move, from "more complicated" to "complex". But it lacks the Part vs. Whole move, since both the premise and the conclusion are about the plot.
5% picked this
Mathematics is more difficult than
No Relative vs. Absolute
This does have a Part to Whole move, from "math / history" to "math test / history test". But it lacks a a Relative vs. Absolute move, since both the premise and the conclusion deal with "more difficult".
8% picked this

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