Sections 2

Sign up to star your favorites LSAT 122 - Section 2 - Question 11

April 21, 2012

Cookie Cutter Review
Causation
(A) direct cause
(B) alternate cause
(D) direct cause
(E) corroborating data

Cholesterol, which is a known factor in coronary heart disease and stroke, needs a carrier, known as a lipoprotein, to transport it through the bloodstream. Low-density lipoproteins (LDLs) increase the risk of coronary heart disease and stroke, but we can tentatively conclude that high-density lipoproteins (HDLs) help prevent coronary heart disease and stroke. First, aerobic exercise increases one’s level of HDLs. Second, HDL levels are higher in women than in men. And both aerobic exercise and being female are positively correlated with lower risk of coronary heart disease and stroke.

Summarize Argument: Phenomenon-Hypothesis

The author hypothesizes that HDLs prevent heart disease and stroke. This is based on a few phenomena: cardio increases HDL levels, women have higher HDL levels, and both cardio and being female are correlated with a lower risk of heart disease and stroke.

Notable Assumptions

The author assumes causation from correlation. There could be a number of other factors that explain the phenomena described. For example, maybe exercise just improves overall health, and maybe women tend to exercise more than men, which is why exercise and being female are correlated with fewer heart issues.

A

HDLs, unlike LDLs, help the body excrete cholesterol.

This strengthens the argument. (A) says HDLs, unlike LDLs, help the body get rid of something that is known to contribute to heart disease and stroke: cholesterol.

B

Persons who are overweight tend to have a higher risk of early death due to coronary heart disease and stroke, and tend to have low levels of HDLs.

This strengthens the argument by offering a correlation between low HDL levels and higher risk of fatal heart disease and stroke. This reinforces the correlation described in the stimulus (that higher HDL levels are correlated with lower risk of these conditions).

C

HDLs are less easily removed from the bloodstream than are LDLs.

This does not affect the argument. While we know that LDLs increase the risk of heart disease and stroke, we don’t know anything about how them being more easily removed from the bloodstream affects one’s likeliness to have these conditions.

D

A high level of HDLs mitigates the increased health risks associated with LDLs.

This strengthens the argument. We know that LDLs increase the risk of heart disease and stroke—the idea that HDLs mitigate this risk suggests that they have the opposite impact on one’s risk of heart disease and stroke.

E

Men whose level of HDLs is equal to the average level for women have been found to have a lower risk of coronary heart disease and stroke than that of most men.

This strengthens the argument. (E) says men with above-average HDL levels (relative to other men) have a lower risk of heart disease and stroke than men with average HDL levels. (E) offers another correlation between high HDL levels and low risk of the conditions.

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Sign up to star your favorites LSAT 122 - Section 2 - Question 12

April 21, 2012

It is primarily by raising interest rates that central bankers curb inflation, but an increase in interest rates takes up to two years to affect inflation. Accordingly, central bankers usually try to raise interest rates before inflation becomes excessive, at which time inflation is not yet readily apparent either. But unless inflation is readily apparent, interest rate hikes generally will be perceived as needlessly restraining a growing economy. Thus, central bankers’ success in temporarily restraining inflation may make it harder for them to ward off future inflation without incurring the public’s wrath.

Summarize Argument

Central bankers’ success in curbing inflation may make it harder for them to prevent future inflation without making the public angry. Why?
Inflation is restrained by raising interest rates.
These increases take two years to affect inflation.
Therefore, bankers try to increase rates before inflation gets bad. (sub-conclusion)
When inflation is not yet bad, it is not readily apparent.
If inflation is not yet bad, rate increases are seen as hurting the economy.

Identify Argument Part

This is one premise that sets up the explanation for why successful inflation control makes it harder to continue to control it without incurring public anger. Knowing that inflation is restrained by raising interest rates is essential to the argument.

A

It is presented as a complete explanation of the fact that central bankers’ success in temporarily restraining inflation may make it harder for them to ward off future inflation without incurring the public’s wrath.

This is not the complete explanation. It is one premise within the argument that explains why in combination with other premises.

B

It is a description of a phenomenon for which the claim that an increase in interest rates takes up to two years to affect inflation is offered as an explanation.

This is just a premise about inflation control. It is not explained or supported by other parts of the argument.

C

It is a premise offered in support of the conclusion that central bankers’ success in temporarily restraining inflation may make it harder for them to ward off future inflation without incurring the public’s wrath.

This is accurate - it is a premise that supports this main conclusion.

D

It is a conclusion for which the statement that an increase in interest rates takes up to two years to affect inflation is offered as support.

It is not the conclusion, it is a premise. The claim receives no support.

E

It is a premise offered in support of the conclusion that unless inflation is readily apparent, interest rate hikes generally will be perceived as needlessly restraining a growing economy.

This is not the conclusion that the answer choice supports. The conclusion cited here is just another premise.

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Sign up to star your favorites LSAT 122 - Section 2 - Question 13

April 21, 2012

A survey of clerical workers’ attitudes toward their work identified a group of secretaries with very positive attitudes. They responded “Strongly agree” to such statements as “I enjoy word processing” and “I like learning new secretarial skills.” These secretaries had been rated by their supervisors as excellent workers—far better than secretaries whose attitudes were identified as less positive. Clearly these secretaries’ positive attitudes toward their work produced excellent job performance.

A

It attempts to prove a generalization about job performance by using the single example of clerical workers.

This is the cookie-cutter flaw of hasty generalization. But the author doesn't attempt to prove an overly broad generalization about all job performance. Instead, she uses an example of clerical workers to draw a conclusion about those same clerical workers.

B

It restates the claim that the secretaries’ positive attitudes produced their excellent job performance instead of offering evidence for it.

This is the cookie-cutter flaw of circular reasoning, where the conclusion simply restates a premise. The author’s premises and conclusion are distinct. One premise points out a correlation between positive attitudes and job performance, while her conclusion is about causation.

C

It does not consider the possibility that secretaries with very positive attitudes toward their work might also have had very positive attitudes toward other activities.

It doesn't matter whether the secretaries have positive attitudes toward other activities outside of work. The argument just addresses their positive attitudes toward work, claiming that this causes their excellent job performance.

D

It uses the term “positive attitudes” to mean two different things.

This is the flaw of equivocation, where an argument uses one term in different ways. The author doesn’t make this mistake; she uses “positive attitudes” clearly and consistently throughout her argument, always referring to the secretaries’ positive attitudes toward their work.

E

It identifies the secretaries’ positive attitudes as the cause of their excellent job performance although their attitudes might be an effect of their performance.

The author argues that the positive attitudes caused excellent performance, without considering that excellent performance might actually have caused the positive attitudes. She sees a correlation between X and Y, then jumps to the conclusion that X caused Y.

Cookie Cutter Review
Flaw - (E) is cause-effect confusion
(A) sample size too small / over-generalization
(B) circular reasoning
(D) equivocation

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Sign up to star your favorites LSAT 122 - Section 2 - Question 14

April 21, 2012

Scientist: A controversy in paleontology centers on the question of whether prehistoric human ancestors began to develop sophisticated tools before or after they came to stand upright. I argue that they stood upright first, simply because advanced toolmaking requires free use of the hands, and standing upright makes this possible.

Summarize Argument: Phenomenon-Hypothesis

The scientist hypothesizes that prehistoric human ancestors stood upright before they developed sophisticated tools. This is based on the idea that making these tools required the free use of their hands, which standing would have provided.

Notable Assumptions

The scientist assumes that standing up, a sufficient condition for the free use of hands, is also a necessary condition for the free use of hands. In other words, the scientist assumes there is no other way prehistoric human ancestors could have freed their hands without standing. This overlooks alternative explanations, such as sitting, which also allows for hands to be freed.

A

Many animals that do not stand upright have learned to make basic tools.

This does not affect the argument, which is concerned with sophisticated tools, not basic ones.

B

Advanced hunting weapons have been discovered among the artifacts belonging to prehistoric human ancestors who did not stand upright.

This weakens the argument. It attacks the assumption that standing up is a necessary condition for the free use of hands, which (B) says is not true. If prehistoric human ancestors made advanced weapons without standing up, they must have freed their hands without standing.

C

Many prehistoric human ancestors who stood upright had no sophisticated tools.

This does not affect the argument, as the scientist does not argue that prehistoric human ancestors stood because they required sophisticated tools.

D

Those prehistoric human ancestors who first came to stand upright had no more dexterity with their hands than did those who did not stand upright.

This does not affect the argument. The scientist argues that prehistoric human ancestors stood before they made tools because they required the free use of their hands, not because standing made their hands more dexterous.

E

Many of the earliest sophisticated tools did not require their users to be able to stand upright.

This does not affect the argument. The scientist is concerned with whether the people who made the tools needed to stand, not with whether the people who used the tools needed to stand.

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Sign up to star your favorites LSAT 122 - Section 2 - Question 15

April 21, 2012

Cookie Cutter Review
PSA - (C) says P -> C

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Sign up to star your favorites LSAT 122 - Section 2 - Question 16

April 21, 2012

Most successful entrepreneurs work at least 18 hours a day, and no one who works at least 18 hours a day has time for leisure activities. But all happy entrepreneurs have time for leisure activities.

Summary

The stimulus can be diagrammed as follows:

Notable Valid Inferences

Most successful entrepreneurs are not happy.

Most successful entrepreneurs don’t have leisure time.

A

Anyone who has no time for leisure activities works at least 18 hours a day.

This could be true. From the diagram, we see “18+ hrs/day→ /leisure time.” (A) says /leisure time→ 18+ hrs/day. (A) confuses the sufficient and necessary conditions. It’s not a MBT, but it could be true.

B

Some entrepreneurs who work at least 18 hours a day are successful.

This must be true. We already know that most successful entrepreneurs work 18+ hrs/day, so it is the case that some entrepreneurs who work 18+ hrs/day are successful.

C

Some happy entrepreneurs are successful.

This could be true. We know that most successful entrepreneurs are not happy, but this does not mean that there is no overlap between entrepreneurs that are successful and those who are happy. “Most” doesn’t mean “all.”

D

Some entrepreneurs who work at least 18 hours a day are happy.

This must be false. We know that all people who work 18+ hrs/day are unhappy. This means that all entrepreneurs who work that much are unhappy. It must be false that someone in this group is happy.

E

Some successful entrepreneurs work less than 18 hours a day.

This could be true. We know that most successful entrepreneurs work 18+ hrs/day, but most doesn’t mean all. It could definitely be the case that some successful entrepreneurs work less than 18 hrs/day.

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Lawgic, formulaic

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Sign up to star your favorites LSAT 122 - Section 2 - Question 17

April 21, 2012

Cookie Cutter Review
NA - premise-conclusion bridge

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Sign up to star your favorites LSAT 122 - Section 2 - Question 18

April 21, 2012

New Age philosopher: Nature evolves organically and nonlinearly. Furthermore, it can best be understood as a whole; its parts are so interconnected that none could exist without support from many others. Therefore, attaining the best possible understanding of nature requires an organic, holistic, nonlinear way of reasoning rather than the traditional linear reasoning of science, which proceeds through experiments on deliberately isolated parts of nature.

A

takes for granted that if a statement must be true for the argument’s conclusion to be true, then that statement’s truth is sufficient for the truth of the conclusion

This is the cookie-cutter flaw of confusing sufficient and necessary conditions. The philosopher doesn’t make this mistake; his premises don’t contain any conditional claims.

B

overlooks the possibility that the overall structure of a phenomenon is not always identical to the overall structure of the reasoning that people do about that phenomenon

The philosopher suggests that the overall structure of nature is identical to the overall structure of the reasoning that must be used to best understand nature, not the reasoning that people actually do about nature.

C

fails to distinguish adequately between the characteristics of a phenomenon as a whole and those of the deliberately isolated parts of that phenomenon

The philosopher doesn’t fail to distinguish between the characteristics of nature as a whole and the characteristics of its parts. Instead, he fails to explain why the characteristics of nature must be the same as the characteristics of the reasoning used to understand nature.

D

takes for granted that what is interconnected cannot, through abstraction, be thought of as separate

The philosopher doesn’t assume that the interconnected parts of nature cannot be thought of as separate; in fact, he says that scientific reasoning deliberately isolates parts of nature. He just claims that the interconnected parts of nature should not be thought of as separate.

E

takes for granted that a phenomenon that can best be understood as having certain properties can best be understood only through reasoning that shares those properties

The philosopher assumes that because nature is nonlinear, organic, and holistic, it can best be understood only through reasoning that’s also nonlinear, organic, and holistic. But what if nature is better understood through another kind of reasoning, like scientific reasoning?

Cookie Cutter Review
(E) conflation of distinct ideas. Understanding that a phenomenon has property X doesn't mean that we should use reasoning with property X to understand that phenomenon.

Supplementary explanation
This is a very silly argument that reads like it's actually reasonable.

We're presented with a thing called nature. We're told that nature has certain properties, XYZ. Therefore, we're told, that the thinking used to understand nature should also have those properties, XYZ.

This argument is insane. It escapes our insanity detector only because the LSAT writers are clever and picked out the "XYZ" so as not to raise alarm. They wrote "organic, holistic, etc", which to us are familiar properties of thinking/reasoning.

But by that logic, I can say, "Hey look at that stupid bear over there, scratching his ass on that tree cause his stupid paws can't reach. The best way to understand the bear is as a hairy beast. Therefore, use we should use our hairy beastly thinking when trying to study and analyze the bear."

Can we all say in unison: "No, dumbass. Use Biology."

See how that didn't escape our insanity detector? That's because "hairy beastly thinking" is obviously not a thing whereas "organic holistic thinking" is.

(E) calls the argument out on its absurdity. Properties of the object to be studied shouldn't be projected onto the reasoning used to study that object.

(B) is having his own conversation over in the corner of the room by himself. It's saying that the structure of nature isn't identical to the structure of how people reason about nature. Okay, sure. Let's not even argue what the overall "structure" of nature is and just concede that it's "organic". So (B) is saying that that's not always identical to the structure of how people reason about nature. In other words, people don't always reason organically about it. Again, okay sure. So what? Is that a bad thing? Should people reason organically about it?

The argument isn't terrible because sometimes the structure of a phenomenon is not identical with the structure of reasoning people use to understand that phenomenon.

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Sign up to star your favorites LSAT 122 - Section 2 - Question 19

April 21, 2012

Cookie Cutter Review
SA - formulaic

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Sign up to star your favorites LSAT 122 - Section 2 - Question 20

April 21, 2012

Environmentalist: Discarding old appliances can be dangerous: refrigerators contain chlorofluorocarbons; electronic circuit boards and cathode-ray tubes often contain heavy metals like lead; and old fluorescent bulbs contain mercury, another heavy metal. When landfills are operated properly, such materials pose no threat. However, when landfills are not operated properly, lead and mercury from them contaminate groundwater, for example. On the other hand, when trash is incinerated, heavy metals poison the ash and escape into the air.

Summary

Discarding old appliances can be dangerous because some contain harmful heavy metals. When landfills are operated properly, the heavy metals pose no threat. When landfills are not operated properly, lead and mercury can contaminate groundwater. When trash is burned, heavy metals poison the ash and are released into the air.

Strongly Supported Conclusions

Old appliances that contain heavy metals should not be burned when discarded.

A

Old fluorescent bulbs should be recycled.

This answer is unsupported. We don’t know from the stimulus what “recycling” involves. We only know from the stimulus that old fluorescent bulbs should not be incinerated.

B

Appliances containing heavy metals should not be incinerated.

This answer is strongly supported. Since incineration causes heavy metals to poison the ash, these appliances should not be incinerated.

C

Chlorofluorocarbons are harmful to the atmosphere.

This answer is unsupported. We only know from the stimulus that heavy metals, when incinerated, are harmful to the atmosphere. It’s unclear from the stimulus whether chlorofluorocarbons are heavy metals.

D

Newer appliances are more dangerous to the environment than older ones.

This answer is unsupported. The stimulus is limited to older appliances. We don’t know anything about newer appliances in order to draw this comparison.

E

Appliances should be kept out of landfills.

This answer is unsupported. The stimulus is limited to older appliances. This answer applies to appliances generally and is therefore too strong.

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