In this section we present and analyze two Logical Reasoning questions drawn
from real LSATs. We will use the two examples to discuss the various answer
types presented in the previous section and to discuss the language used by the
test makers in the answer choices.
Please take a moment to complete the following problem:
1. Garbage in this neighborhood probably will not be collected until Thursday this week. Garbage is usually collected here on Wednesdays, and the garbage collectors in this city are extremely reliable. However, Monday was a public holiday, and after a public holiday that falls on a Monday, garbage throughout the city is supposed to be collected one
day later than usual.
The argument proceeds by
(A) treating several pieces of irrelevant evidence
as though they provide support for the
conclusion
(B) indirectly establishing that one thing is likely
to occur by directly ruling out all of the
alternative possibilities
(C) providing information that allows application
of a general rule to a specific case
(D) generalizing about all actions of a certain kind
on the basis of a description of one such
action
(E) treating something that is probable as though
it were inevitable
As usual, we begin by analyzing the structure of the problem:
Premise: Garbage is usually collected here on Wednesdays, and the
garbage collectors in this city are extremely reliable.
Premise: Monday was a public holiday.
Premise: After a public holiday that falls on a Monday, garbage
throughout the city is supposed to be collected one day later
than usual.
Conclusion: Garbage in this neighborhood probably will not be collected
until Thursday this week.
The argument is sound and the conclusion seems reasonable. The language in
the conclusion is not absolute (“probably”), and this is justified since the
language used in the argument—“usually” and “supposed to be”—is also
probabilistic. Knowing that the argument is valid, the question you must ask
yourself is, “How would I describe the structure of this argument?”
Answer choice (A): This answer forces you to make an assessment of the
premises (the “evidence”) as they relate to the conclusion. Are the premises
irrelevant to the conclusion? Clearly not. Therefore, this answer is incorrect.
Answer choice (B): This is a half-right, half-wrong answer. The argument does
establish “that one thing is likely to occur.” But, is this established by ruling out
all of the alternative possibilities? No, to do that would mean presenting
arguments against the garbage being collected on Friday, Saturday, Sunday, etc.
Since this section of the answer choice does not occur, this answer is incorrect.
Also, because the argument does not rule out all the alternatives, the conclusion
is not established “indirectly.”
Answer choice (C): This is the correct answer. Consider each piece of the
argument:
“providing information”—a variety of information about the garbage
situation is provided.
“application of a general rule”—the general rule is that “After a public
holiday that falls on a Monday, garbage throughout the city is supposed
to be collected one day later than usual.”
“to a specific case”—the specific case is the pickup of garbage this week in
this neighborhood.
Given that all elements occurred and the answer presents an accurate
description of the way the author made his or her argument, this answer is
correct. Now, take a moment and compare this answer to the prephrase you
made after reading the stimulus. How similar are the two? Given that you may
not be familiar with the language used by the test makers, the two may not be
very similar. As your preparation continues, you will become more comfortable
with the language and your Method of Reasoning prephrasing will improve.
For example, note the use in this answer of “general rule” to describe the last
sentence of the stimulus. The test makers could also have used a phrase like
“basic principle” to achieve the same result. Your job is to match their language
to what occurred in the stimulus.
Answer choice (D): This answer is an overgeneralization—a situation where
one instance is used to make a broad based conclusion. This is a Reverse
Answer since the stimulus actually uses a general principle and applies it to one
instance. In addition, the language in the answer is far too strong in saying “all
actions of a certain kind” when the language in the stimulus was probabilistic.
Answer choice (E): This is an Exaggerated Answer. The conclusion states that
“Garbage in this neighborhood probably will not be collected until Thursday
this week” and the use of “probably” is a clear and obvious indication that the
author does not think the Thursday garbage pickup is inevitable.
Now try another. Please take a moment to complete the following problem:
2. Jane: Professor Harper’s ideas for modifying the design of guitars are of no value
because there is no general agreement among musicians as to what a guitar should sound
like and, consequently, no widely accepted basis for evaluating the merits of a guitar’s sound.
Mark: What’s more, Harper’s ideas have had enough time to be adopted if they really resulted in superior sound. It took only ten years for the Torres design for guitars to be almost universally adopted because of the improvement it makes in tonal quality.
Which one of the following most accurately
describes the relationship between Jane’s argument
and Mark’s argument?
(A) Mark’s argument shows how a weakness in
Jane’s argument can be overcome.
(B) Mark’s argument has a premise in common
with Jane’s argument.
(C) Mark and Jane use similar techniques to argue
for different conclusions.
(D) Mark’s argument restates Jane’s argument in
other terms.
(E) Mark’s argument and Jane’s argument are
based on conflicting suppositions.
This is one of the greatest LSAT Method of Reasoning questions of all time.
First take a close look at the statements made by Jane and Mark.
Jane’s position: Jane concludes that Professor Harper’s ideas are valueless
because there is no way to evaluate a guitar sound and determine what
constitutes a better-sounding guitar.
Mark’s position: Mark also agrees that Professor Harper’s ideas are
valueless, but Mark’s reasoning is that if Harper’s ideas really worked,
then they would have been adopted by now. In making this analysis,
Mark reveals that he believes there is a way to determine that one guitar
sounds better than another.
Like all LSAT questions, you must lock down the exact nature of the premises
and conclusions! Mark’s initial comment of “What’s more” leads most people to
believe he is in complete agreement with Jane. Yes, he agrees with her
conclusion, but his reason for doing so is completely contrary to Jane’s reason.
Mark actually misinterprets Jane’s claim, and this is why he says “What’s
more,” as if he is adding an additional piece of information that supports her
position. He is not; the premise that he uses contradicts Jane’s premises. If you
simply accept “What’s more” to mean that he is in complete agreement with
Jane, you will most certainly miss the question, and have no idea you have done
so.
The problem becomes even more challenging because the answer choices are
brilliantly constructed:
Answer choice (A): Mark does not address a weakness in Jane’s argument or
show how one could be overcome. Do not mistake the use of “What’s more” to
automatically mean that he is adding something helpful to the situation.
Answer choice (B): This is an answer chosen by many people, and it has Shell
game aspects. Mark’s argument does not have a premise in common with Jane’s
argument; rather, Mark’s argument has the conclusion in common with Jane’s
argument.
Before you select this answer, use the Fact Test and ask yourself, “Which
premise do the two arguments have in common?” You won’t be able to find
one, and that would instantly disprove the answer.
Answer choice (C): This is a very clever Reverse Answer choice. The answer
states:
“Mark and Jane use similar techniques to argue for different
conclusions.”
In fact, the following happens in the stimulus:
“Mark and Jane use different techniques to argue for similar
conclusions.”
If you had any doubt that the makers of the LSAT put the same amount of work
into the wrong answers as the correct answers, this answer choice should be
convince you that they do.
Answer choice (D): An argument is the sum of the premises and conclusion.
Although Mark restates Jane’s conclusion, he does not restate her premises.
Therefore, he does not restate her argument and this answer is incorrect.
Answer choice (E): This is the correct answer. As discussed in the argument
analysis, Jane believes that there is no way to evaluate the merit of a guitar’s
sounds. On the opposite side, Mark’s response indicates he believes that there is
a way to evaluate the merit of a guitar’s sound (“because of the
improvement it makes in tonal quality”) and thus the two have conflicting
positions.
This is another great example of a separator question: one that scorers in a
certain range will get and scorers in a lower range will not get. This is also a
dangerous question because many people think they have chosen the correct
answer when in fact they have missed it. The lesson here is that you must be an
active, prepared reader. Do not allow yourself to be lulled by Mark’s comment
of “What’s more” into believing that he automatically is in agreement with Jane.
The test makers use that phrase to see if you will read closely enough to discern
his real argument or if you will simply gloss over his comments on the basis of
how they are introduced. The LSAT always makes you pay if you gloss over
any section of a stimulus.
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