Section Types Logical Reasoning

LSAT 144 - Section 2 - Question 05

December 17, 2015

LSAT 76 - Section 2 - Question 04

December 17, 2015

LSAT 144 - Section 2 - Question 04

December 17, 2015

Biologist: A careful study of the behavior of six individual chameleons concluded that lizards such as chameleons bask in the sun not only for warmth but also to regulate their production of vitamin D. Critics of the study—although correct in observing that its sample size was very small—are wrong to doubt its results. After all, the study’s author is well regarded professionally and has been doing excellent work for years.

Summarize Argument

The author concludes that critics of a study involving chameleons are wrong to doubt the study’s conclusion. This is based on the fact that the study’s author is well-regarded professionally and has been doing excellent work for years.

Identify and Describe Flaw

The professional reputation and background of the study’s author doesn’t constitute a reason to trust the study’s conclusion. What matters is how the study was conducted and whether the study’s conclusion is reasonable.

A

takes the behavior of chameleons to be generalizable to lizards as a whole

The author’s reasoning isn’t based on generalizing from chamelons to lizards as a whole. The reasoning is based on the study author’s background and whether that shows the results are reliable.

B

fails to explain how chameleons regulate their vitamin D production by basking in the sun

The author didn’t need to explain how chameleons regulate their vitamin D. This issue doesn’t affect whether the study author’s background constitutes a reason to find the conclusion reliable.

C

focuses its attention on the study’s author rather than on the study itself

The author focuses on the study author’s professional reputation and background rather than on the study itself. This is a flaw, because the author’s reputation and background do not reveal anything about the reliability of the study and its conclusion.

D

fails to demonstrate that the study’s critics have relevant expertise

The argument doesn’t rely on the study’s critics for support, so their expertise is irrelevant.

E

holds the study’s author to a higher standard than it holds the study’s critics

The argument doesn’t concern different standards for different people. The author simply believes that the reputation/background of the study’s author constitutes a reason to trust the study’s conclusion.

5 comments

LSAT 76 - Section 2 - Question 03

December 17, 2015

5 comments

LSAT 144 - Section 2 - Question 03

December 17, 2015

Doris: I’ve noticed that everyone involved in student government is outspoken. So if we want students to be more outspoken, we should encourage them to become involved in student government.

Zack: Those who are in student government became involved precisely because they are outspoken in the first place. Encouraging others to become involved will do nothing to make them more outspoken.

Speaker 1 Summary

Doris concludes that if we want students to be more outspoken, we should encourage them to become involved in student government. This is based on her observation that everyone involved in student government is outspoken. Doris’s argument assumes a causal relationship between involvement in student government and being outspoken.

Speaker 2 Summary

Zack concludes that encouraging people to get involved in student government won’t make them more outspoken. This is because being outspoken is the cause of involvement in student government.

Objective

We’ re looking for a point of disagreement. The speakers disagree about the direction of the causal relationship between involvement in student government and being outspoken. Doris thinks involvement causes being outspoken. Zack thinks the relationship is reversed.

A

students should be more outspoken

Neither speaker expresses an opinion. Doris doesn’t say we want students to be outspoken, only what we should do if we want them to be more outspoken. Zack doesn’t say anything should or should not happen.

B

students should be encouraged to become involved in student government

Neither speaker expresses an opinion. Doris only says we should encourage student government involvement if we want students to be more outspoken. That’s not the same as wanting students to be more involved in student government. Zack doesn’t say what should or should not happen.

C

becoming involved in student government makes students more outspoken

This is a point of disagreement. Doris thinks involvement in student government makes students more outspoken. Zack doesn’t think so.

D

all students who are involved in student government are outspoken

This is not a point of disagreement. Although Doris agrees with this, Zack also could agree. He doesn’t say that there are any students involved in student government who are not outspoken.

E

students will not become more outspoken unless they become involved in student government

Neither speaker expresses an opinion. Doris thinks involvement causes becoming more outspoken. But she doesn’t suggest that involvement is required. Zack also does not suggest that involvement is required to be outspoken.

5 comments

LSAT 76 - Section 2 - Question 02

December 17, 2015

1 comment

LSAT 144 - Section 2 - Question 02

December 17, 2015

Government official: Residents who are foreign citizens can serve as public servants at most levels, but not as cabinet secretaries. This is wise, since cabinet secretaries perform some duties that should be performed only by citizens, and no one should be appointed to a position if it involves duties that person should not perform. Moreover, a cabinet undersecretary is expected to serve as cabinet secretary when the actual secretary is unavailable. So, _______.

Summary

The stimulus sets forth several rules.

Foreign citizens cannot serve as cabinet secretaries. This is justified because cabinet secretaries need to do things that only domestic citizens can do (and foreign citizens can’t do).

No one should be appointed to a position that involves duties a person can’t perform.

In addition, a cabinet undersecretary is expected to serve as cabinet secretary when the actual cabinet secretary is unavailable.

Strongly Supported Conclusions

Since cabinet undersecretaries are expected to serve as cabinet secretaries at some times, and foreign citizens can’t serve as cabinet secretaries, this strongly suggests foreign citizens shouldn’t serve as cabinet undersecretaries.

A

foreign citizens who serve as public servants should be granted citizenship in the country they serve

Unsupported. Nothing in the stimulus concerns conditions for granting citizenship. We know that non-citizens shouldn’t serve in certain positions. That doesn’t imply we should ever make them citizens.

B

foreign citizens should not be appointed as cabinet undersecretaries

Strongly supported. Foreign citizens can’t serve as cabinet secretaries, so they shouldn’t serve as undersecretaries, who would be expected to occasionally step in as cabinet secretaries. No one should be appointed to a position whose duties they can’t fulfill.

C

only former cabinet undersecretaries should be appointed as cabinet secretaries

Unsupported. We know foreign citizens shouldn’t be cabinet secretaries. But nothing excludes non-former-undersecretaries from serving as cabinet secretaries.

D

foreign citizens should be eligible to serve as cabinet secretaries

Unsupported. The author doesn’t provide reasons to change the current restrictions on service. The stimulus simply describes the rules, and we are supposed to apply them. Not advocate for a change.

E

cabinet undersecretaries should not be expected to stand in for cabinet secretaries

Unsupported. We’re not given reasons that undersecretaries shouldn’t step in for the secretaries. We’re given reasons a foreign citizen should not serve as an undersecretary or secretary. The stimulus doesn’t give us enough to infer that rules should be changed.

1 comment

LSAT 76 - Section 2 - Question 01

December 17, 2015

7 comments

LSAT 144 - Section 2 - Question 01

December 17, 2015

In the bodies of reptiles, some industrial by-products cause elevated hormonal activity. Hormones govern the development of certain body parts, and in reptiles abnormal development of these parts occurs only with elevated hormonal activity. Recently, several alligators with the telltale developmental abnormalities were discovered in a swamp. So, apparently, industrial by-products have entered the swamp’s ecosystem.

Summarize Argument: Phenomenon-Hypothesis

The author concludes that industrial by-products have entered the swamp’s ecosystem. This is based on the following:

Some industrial by-products cause elevated hormonal activity.

Recently, some reptiles in this swamp had abnormal development that occurs only with elevated hormonal activity.

Identify and Describe Flaw

The author assumes that there’s no other cause of the elevated hormonal activity besides the industrial by-products. This overlooks the possibility that the reptiles’ hormonal activity could be due to something else, in which case, we cannot conclude that industrial by-products have entered the swamp.

A

provides no explanation for developmental abnormalities that do not result from elevated hormonal activity

The argument concerns abnormalities that are caused only be elevated hormonal activity. Other abnormalities don’t have any impact on the reasoning.

B

fails to consider whether elevated hormonal activity can result from factors other than the presence of industrial by-products

If elevated hormonal activity can result from things besides industrial by-products, then the elevated hormonal activity that the reptiles in the swamp have does not prove that there are industrial by-products in the swamp. The elevated hormones might result from other things.

C

fails to address the possibility that industrial by-products were contained in food the alligators ate

The author doesn’t make any assumption about exactly how the by-products got into the reptiles in the swamp. Maybe the reptiles ate food in the swamp, and that food contained the by-products. This doesn’t undermine the author’s reasoning.

D

fails to say whether reptiles other than alligators were examined for the same developmental abnormalities that were discovered in the alligators

We know there are reptiles in the swamp with the abnormalities that are only caused by elevated hormonal activity. Whether there are other reptiles that have those abnormalities or not has no impact on the reasoning.

E

uses evidence drawn from a sample of alligators that is unlikely to be representative of alligators in general

The conclusion doesn’t concern alligators in general. So there’s nothing flawed about relying on evidence drawn from a sample of alligators in the swamp.

7 comments

LSAT 33 - Section 1 - Question 18

October 24, 2015

62 comments