Aiesha: You seem to forget that drivers exceed the speed limit more frequently and drive close to the road edge more frequently on roads that are marked with reflecting posts than on similar roads without posts, and those are driving behaviors that cause road accidents.
Summarize Argument: Phenomenon-Hypothesis
Aiesha rejects Adam’s claim that marking road edges with reflecting posts will decrease the number of road accidents. As evidence, Aiesha points out that drivers speed and drive closer to a road’s edges when roads are marked with reflecting posts. Moreover, these are the driving behaviors that cause road accidents.
Describe Method of Reasoning
Aiesha counters the position held by Adam. She does this by presenting an additional consideration that weakens an assumption underlying Adam’s argument. Just because roads can enable drivers to drive more safely does not mean those drivers will in fact drive more safely.
A
questioning Adam’s assertion that reflecting posts give drivers a clear view of road edges
Aiesha does not state that reflecting posts do not give drivers a clear view. In fact, Aiesha suggests that this clear view is correlated with dangerous driving behaviors.
B
presenting a possible alternative method for decreasing road accidents
Aiesha does not propose an alternative method for decreasing road accidents. She only addresses the method of installing reflecting posts on roadway edges.
C
raising a consideration that challenges the argument’s assumption that facilitating safe driving will result in safer driving
Adam’s assumption is that reflecting posts actually cause drivers to drive more safely. The consideration Aiesha raises to challenge this is that drivers speed and drive closer to road edges when there are reflecting posts.
D
denying that the drivers’ view of the road is relevant to the number of road accidents
Aiesha does not claim that a driver’s view is not relevant to the number of road accidents. In fact, Aiesha agrees that this is a relevant factor because dangerous driving behaviors increase when there are reflecting posts.
E
providing additional evidence to undermine the claim that safer driving does not necessarily reduce the number of road accidents
Adam does not conclude that safer driving does not necessarily reduce the number of road accidents. In fact, Adam’s argument indicates the opposite. Aiesha does not address the conclusion described in this answer choice.
Summarize Argument: Phenomenon-Hypothesis
The researchers hypothesize that video display terminals (VDTs) cause headaches. They base this hypothesis on survey data that showed that office workers who frequently used VDTs experienced headaches more often than other office workers.
Notable Assumptions
The researchers are assuming a causal relationship from the data that shows a correlation between frequent use of VDTs and frequent headaches. This means that they are assuming that the causal relationship is not reversed (in other words, that frequent headaches cause office workers to use VDTs more often). They are also assuming that some outside factor is not causing both the headaches and the frequent VDT use. Additionally, the researchers are assuming that the data from the survey of office workers is accurately reported and representative data.
A
Few of the office workers surveyed participated in regular health programs during the year in question.
(A) does not provide information that weakens the argument. (A) provides information that deals with potential treatment of headaches; the argument concerns the initial cause of headaches.
B
In their study the researchers failed to ask the workers to distinguish between severe migraine headaches and mild headaches.
The severity of headaches does not impact the argument. The conclusion of the argument is that VDTs cause headaches, so it does not matter how severe these headaches are.
C
Previous studies have shown that the glare from VDT screens causes some users to suffer eyestrain.
(C) gives information about another impact of VDTs. It could be the case that VDTs cause eyestrain, which contributes to headaches. But whether or not we assume that eyestrain can lead to headaches, giving information about another result of VDT use does not weaken the argument.
D
Office workers who experienced frequent headaches were more likely than other workers to overestimate how much time they spent using VDTs.
(D) weakens the argument because it provides a reason to doubt the data that the researchers used to form their conclusion. If the survey data is based on overestimation of VDT use, the argument that frequent VDT use causes headaches is weakened.
E
Office workers who regularly used VDTs experienced the same amount of job-related stress as workers who did not use VDTs.
(E) eliminates a potential alternate hypothesis (stress) as a cause for headaches. Controlling for another factor (that could potentially impact headaches) does not weaken the argument that VDTs cause headaches.
Carla: But how do you go about choosing whose perspective is the valid one? Is the foot soldier’s perspective more valid than that of a general? Should it be a French or an English soldier? Your approach would generate a biased version of history, and to avoid that, historians must stick to general and objective characterizations of the past.
Speaker 1 Summary
Mark argues that historians should try to record what it was like to experience past events, which is supported by the reasoning that this approach would convey an understanding of those events. Mark offers the example of a foot soldier’s direct experience of the Battle of Waterloo.
Speaker 2 Summary
Carla claims that historians should instead describe the past in a general and objective way. This is because capturing a direct experience means one must choose which individual’s perspective is most important, which would lead to a biased version of history.
Objective
We need to find a disagreement between Mark and Carla. They disagree about whether historians should try to convey a direct experience of past events.
A
The purpose of writing history is to convey an understanding of past events.
Mark agrees with this, but Carla never disagrees. Carla’s argument never disputes that historians should try to convey an understanding of past events—the issue is just the perspective they use to do so.
B
The participants in a battle are capable of having an objective understanding of the ramifications of the events in which they are participating.
Neither speaker agrees or disagrees with this claim. Mark never even mentions objectivity, and Carla never says whether or not individual soldiers can be capable of objectivity.
C
Historians can succeed in conveying a sense of the way events in the distant past seemed to someone who lived in a past time.
Mark seems to agree with this claim, but Carla doesn’t take a position. Carla’s point is that historians shouldn’t try to convey a personal perspective of past events, whether or not that’s actually possible.
D
Historians should aim to convey past events from the perspective of participants in those events.
Mark agrees and Carla disagrees, making this the point of disagreement. This is the conclusion of Mark’s argument, while Carla’s conclusion is that historians should focus on a general, objective perspective instead (meaning they would not use an individual perspective).
E
Historians should use fictional episodes to supplement their accounts of past events if the documented record of those events is incomplete.
Neither speaker talks about the possible use of fiction to supplement historians’ accounts of past events. Fiction doesn’t come up in this discussion at all.
Psychologist: Although studies of young children have revealed important facts about the influence of the environment on language acquisition, it is clear that one cannot attribute such acquisition solely to environmental influences: innate mechanisms also play a role. So, the most reasonable question that ought to be studied is whether _______.
Summary
The Psychologist claims that one cannot attribute children’s development of language solely to environmental influences. Why? Because children’s innate mechanisms also play a role in the development of language.
Strongly Supported Conclusions
So, the most reasonable question that ought to be studied is whether innate mechanisms or environmental factors play a more significant role for a child’s language development.
A
language acquisition can ever be fully explained
The Psychologist is not concerned if the development of language could ever be fully explained. Rather, the Psychologist is concerned with how language development could be partially explained.
B
innate mechanisms are a contributing factor in language learning
The Psychologist already claims that innate mechanisms play a role in the development of language.
C
language acquisition is solely the product of innate mechanisms
The Psychologist concedes that innate mechanisms are not the sole factor for language development. Rather, the Psychologist is claiming that these mechanisms play a role.
D
parents and peers are the most important influence on a child’s learning of a language
We don’t know whether parents and peers are the most important influence for developing language. We only know that environmental factors and innate mechanisms influence this development in some way.
E
innate mechanisms play a more important role in language acquisition than a child’s immediate environment
We know from the Psychologist that innate mechanisms play a partial role and environmental factors are not the sole influence on the development of language. Therefore, the next logical step is to consider what proportion of language development could we attribute to each of these factors.
Carla: But how do you go about choosing whose perspective is the valid one? Is the foot soldier’s perspective more valid than that of a general? Should it be a French or an English soldier? Your approach would generate a biased version of history, and to avoid that, historians must stick to general and objective characterizations of the past.
Summarize Argument: Counter-Position
Carla denies Mark’s claim and concludes historians must stick to general and objective characterizations of the past. To support her claim, Carla poses rhetorical questions and states that the answers would generate a biased version of history.
Describe Method of Reasoning
Carla counters the position held by Mark. She does this by posing questions Mark’s argument fails to consider and states the approach would generate biased versions of history.
A
contests Mark’s understanding of historical events
Carla does not contest Mark’s understanding. She suggests that Mark’s proposed process would generate biased versions of history.
B
questions Mark’s presupposition that one person can understand another’s feelings
Carla does not question this presupposition. In fact, it’s implied that Carla agrees that one person can understand another’s feelings because she suggests we can choose between different perspectives.
C
argues that the selection involved in carrying out Mark’s proposal would distort the result
The selection involved is the selection of choosing which perspective is valid. The distorted result are the biased versions of history Carla claims Mark’s process would produce.
D
questions whether Mark accurately describes the kind of historical writing he deplores
Mark does not state that he deplores a certain kind of historical writing. We cannot assume that just because Mark prefers historical writing to be done a certain way, Mark deplores other kinds of historical writing.
E
gives reason to believe that Mark’s recommendation is motivated by his professional self-interest
Carla does not address any of Mark’s self-interests. Carla addresses Mark’s argument directly without focusing on personal characteristics.
Summarize Argument
The author concludes that people who lived a century ago probably read a lot more than we read today. As support for this theory, the author cites the fact that those who lived a century ago had very few diversions to amuse them.
Notable Assumptions
The author is assuming that a lack of diversions would lead to people choosing to read more, as opposed to some other activity that could provide amusement. The author is also assuming that enough people were literate a century ago to read “much more” than people read today. Additionally, the author is assuming that people had enough free time to read at a similar level to the amount of time that people spend reading today.
A
Many of the books published a century ago were of low literary quality.
Just because books are of low literary quality does not mean that people won’t be reading them. Also, (A) does not compare literary quality of books a century ago with literary quality of books today. It could be that many books published today are also of low literary quality.
B
On average, people who lived a century ago had considerably less leisure time than we do today.
(B) gives a reason that, even though people a century ago had fewer sources of diversion, they may not have read much more than we do today. Even if people today have more options for diversion, if we have more time to fill, we could be reading more than people a century ago.
C
The number of books sold today is larger than it was a century ago.
More total book sales does not necessarily indicate more time spent reading per capita. Also, the population today is much higher than it was a century ago, which would account for the increase in book sales without an increase in time that people spend reading.
D
On the average, books today cost slightly less in relation to other goods than they did a century ago.
The argument connects available diversions to time spent reading, so book cost is out of the scope of the argument. Also, (D) compares book costs with the cost of goods in general, not the cost of other sources of amusement. Books could have been a cheap source of amusement.
E
One of the popular diversions of a century ago was horse racing.
The author only claims that there were fewer diversions a century ago, not that reading was the only diversion. Also, (E) does not make a comparison between conditions a century ago and conditions today.
Summarize Argument
The advertisement concludes that customers are assured a fair price on diamonds at Gem World. This is because all diamonds sold at Gem World are certified in writing.
Notable Assumptions
The advertisement assumes that diamonds that are certified in writing are assessed by someone other than the person selling them. Moreover, the advertisement assumes that whoever sells the diamond at Gem World isn’t inclined to lie about the diamond’s quality. If the salesperson wasn’t obliged to provide the written certification, then they may well lie about the quality of the diamond.
A
Many jewelry stores other than Gem World also provide written certification of the quality of their diamonds.
The advertisement doesn’t say Gem World is alone in their practice. It simply says Gem World is preferable from a customer standpoint to most jewelry stores.
B
The certifications of diamonds at Gem World are written by people with years of experience in appraising gems.
This seems to strengthen the argument, but we have no idea if those people are associated with Gem World. If they get some commission on each diamond, they might be inclined to pretend the diamonds are of higher quality than they really are.
C
The diamonds sold at Gem World are generally of higher quality than those sold at other jewelry stores.
We don’t care how high-quality the gems are. We care if Gem World is in fact honest about the quality of each diamond.
D
The diamond market is so volatile that prices of the most expensive diamonds can change by hundreds of dollars from one day to the next.
We don’t care about the exact price. We care if Gem World is in fact honest about the quality of each diamond.
E
The written certifications of diamonds at Gem World are provided by an independent company of gem specialists.
The diamonds are appraised by an independent company that has no stake in how much each diamond sells for. Thus, we can accept that their written certifications probably aren’t biased in favor of Gem World’s business interests.
Summary
Newtonian physics dominated science for over two centuries and became one of the most highly accepted theories in the history of science. Nevertheless, Einstein’s theories later came to show the limits of Newtonian physics and surpassed the Newtonian view in the early 1900s. Einstein’s theories have so far enjoyed wide success.
Notable Valid Inferences
A scientific theory’s widespread acceptance is no guarantee that the theory will be accepted forever.
A
The history of physics is characterized by a pattern of one successful theory subsequently surpassed by another.
Could be false. The stimulus only gives us two examples of scientific theories, one of which subsequently surpassed the other. This doesn’t necessarily establish a pattern, it could be that Newtonian physics and Einstein’s theories are the only examples of this occurring.
B
Long-standing success or substantiation of a theory of physics is no guarantee that the theory will continue to be dominant indefinitely.
Must be true. We know that Einstein’s theories eventually surpasses Newtonian physics despite Newtonian physics dominating science for over two centuries.
C
Every theory of physics, no matter how successful, is eventually surpassed by one that is more successful.
Could be false. The stimulus only gives us two examples of scientific theories, one of which subsequently surpassed the other. This doesn’t necessarily mean that every theory is eventually surpassed. It could be that Einstein surpassing Newtonian physics is a unique occurrence.
D
Once a theory of physics is accepted, it will remain dominant for centuries.
Could be false. We only know that Newtonian physics was dominant for centuries. It could be the case that Newtonian physics is unique, and that no other theory of physics has been accepted for centuries.
E
If a long-accepted theory of physics is surpassed, it must be surpassed by a theory that is equally successful.
Could be false. We know that Einstein’s theories surpassed Newtonian physics, but we cannot assume Einstein’s theories are equally successful. Newtonian physics dominated for over two centuries, and Einstein’s theories have not existed for as long.