Summarize Argument: Counter-Position
The editorial concludes that the nation is not in decline. The support for this conclusion is that essay-writers who claim that the nation is in decline write in anxious tones, which allegedly demonstrates that their claims are influenced by the authors’ own anxieties and therefore do not accurately reflect the nation’s condition.
Identify and Describe Flaw
This is the cookie-cutter flaw of attacking the source of the argument, wherein the author attacks the person or group making the argument instead of going after the argument itself. In this case, the editorial criticizes the psychological states of the writers who claim that the nation is in decline instead of giving any reason to believe that their claims are false. The nation could be declining whether or not these essays are written in an anxious tone!
A
The editorial dismisses a claim without considering any reasons presented in arguments for that claim.
The editorial bases its entire argument on an analysis of the essays’ tones and their authors’ psychological states, rather than presenting any counter-points to the essays’ actual claims. The nation could be declining whether or not the authors are anxious!
B
The editorial compares two situations without considering the obvious differences between them.
This is descriptively inaccurate. The editorial doesn’t compare any situations without considering their differences—the one possible comparison is between the authors’ psychological states and the condition of the nation, and the editorial claims to find a difference there.
C
The editorial confuses claims about a cultural decline with claims about a political decline.
The editorial does not name the type of decline in question, and therefore does not confuse claims about different types of declines.
D
The editorial overlooks the possibility that the nation is neither thriving nor in decline.
The editorial does not argue that the nation is thriving; rather, it concludes that the nation is not in decline. This leaves open the possibility that the nation is neither thriving nor in decline.
E
The editorial dismisses a particular view while offering evidence that actually supports that view.
The evidence doesn’t necessarily support any view on the nation’s condition. It’s possible that the authors’ anxious tones are evidence that they fear the nation’s real decline, but it’s also possible that the tones are alarmist or unrelated to the condition of the nation.
Summarize Argument: Phenomenon-Hypothesis
The author concludes that people’s desire to domesticate animals caused them to develop language. Her premise is that cooperative activities like animal domestication require a sophisticated means of communication such as language.
Identify and Describe Flaw
This is a “correlation doesn’t imply causation” flaw, where the author sees a correlation and concludes that one thing caused the other without ruling out alternative hypotheses. Specifically, she overlooks two key alternatives:
(1) The causal relationship could be reversed—maybe people only thought of domesticating animals because they had developed language and could collectively brainstorm ways to make life easier!
(2) Some other factor could be causing the correlation—maybe human brains had developed to the point where animal domestication and language development were both possible for the first time!
(1) The causal relationship could be reversed—maybe people only thought of domesticating animals because they had developed language and could collectively brainstorm ways to make life easier!
(2) Some other factor could be causing the correlation—maybe human brains had developed to the point where animal domestication and language development were both possible for the first time!
A
conflates being necessary for the development of a phenomenon with guaranteeing the development of that phenomenon
The author doesn’t say that language is necessary for animal domestication. Rather, she claims that a sophisticated mean of communication is necessary, and language is one example of such. Further, the author doesn’t argue that language guarantees the domestication of animals.
B
takes for granted that every phenomenon has a unique cause
The author makes no general claims about the causes of all phenomenons. She also doesn’t even argue that language developed as the result of a unique cause—she just says animal domestication was the primary one!
C
infers that the development of one phenomenon caused the development of another merely because the two phenomena developed around the same time
The author doesn’t use temporal proximity as a premise in her argument—she doesn’t even explicitly state that language and animal domestication developed around the same time!
D
draws a conclusion that merely restates a claim presented in support of that conclusion
The author’s conclusion (that language developed primarily to facilitate animal domestication) is different from her premises (that animal domestication is cooperative and cooperative activities require sophisticated means of communication like language).
E
assumes that if something serves a purpose it must have developed in order to serve that purpose
This is a correlation/causation flaw. The author assumes that, because language provided the sophisticated means of communication required to domesticate animals, the desire for animal domestication caused language development. Maybe language developed for another reason!
Summarize Argument
The author concludes that eating tilapia fillets is a good choice for those who want the benefits of eating fish, but who don’t like the taste of fish. This is based on the fact that tilapia fillets don’t have the strong fishy taste that a lot of people don’t like.
Notable Assumptions
The author assumes that eating tilapia fillets has the same benefits as eating fish typically does.
A
Eating more than the recommended amount of fish can cause toxins that are present in high concentrations in many varieties of fish to accumulate in a person’s body.
This suggests we shouldn’t eat too much fish. But this doesn’t impact the argument concerning whether tilapia is a good choice for people who want the benefits of fish but don’t like the taste of fish.
B
Tilapia are invasive species that crowd out native species of fish in lakes throughout the world.
This suggests tilapia are bad for native fish. But this has nothing to do with whether tilapia is a good choice for people who want the benefits of fish but don’t like the taste of fish.
C
Tilapia fillets contain little of the beneficial fish oils that are the main reason nutritionists recommend eating fish frequently.
This points out that tilapia fillets won’t give people the same benefits of eating fish.
D
Most people who do not care for the taste of fish eat less fish than is recommended by most nutritionists.
This doesn’t impact whether tilapia fillets would be a good choice for people who don’t like the taste of fish.
E
People who rarely or never eat fish usually dislike any food with a strong fishy taste.
Tilapia doesn’t have a strong fishy taste. (E) doesn’t impact whether tilapia fillets would be a good choice for people who don’t like fish.
Summarize Argument
The author concludes that an inexpensive handheld vacuum cleaner is likely to be sufficient for your needs if they are limited to cleaning small areas of uncarpeted floors. This is because most of these vacuums are easy to use and will satisfy vacuuming needs on wood and tile floors.
Notable Assumptions
The author assumes that uncarpeted floors are typically wood or tile. This overlooks the possibility that most uncarpeted floors are made of something besides wood or tile.
A
The only types of floor surfaces that most consumers encounter are carpet, wood, and tile.
This helps establish the truth of the author’s assumption. If the only surfaces most consumers encounter are carpet/wood/tile, then uncarpeted floor tend to be wood/tile. We know the handheld vacuums are likely sufficient for wood/tile.
B
Inexpensive handheld vacuum cleaners are sufficient for cleaning small areas of carpeted floors.
The conclusion concerns people who only need to clean uncarpeted floors. So whether the vacuums are good for carpeted floors has nothing to do with the conclusion.
C
Any handheld vacuum cleaner that is easy to use but sufficient only for cleaning small areas of uncarpeted floors is likely to be inexpensive.
We don’t know whether handheld vacuum cleaners are sufficient “only” for small uncarpeted areas. We’re trying to prove that they are sufficient for those areas, but don’t have premises that establish this.
D
If your household cleaning needs include cleaning small areas of uncarpeted floors, it is likely that you will need a vacuum cleaner.
The argument concerns whether a specific kind of vacuum cleaner would be enough. (D) doesn’t help establish that this kind of vacuum cleaner is enough.
E
The more versatile a vacuum cleaner is, the more likely it is to be expensive.
We have no idea about the versatility of a handheld vacuum cleaner. And (E) doesn’t connect versatility to being enough to clean small uncarpeted areas.
Summary
Images shown to subjects in an experiment usually showed up at the top of the screen but sometimes showed up at the bottom.
When asked to guess where the next image would appear, the subjects were correct less than half of the time.
Their guesses were based on patterns they thought they saw.
If they always guessed that the image would show up at the top, they would guess correctly most of the time.
When asked to guess where the next image would appear, the subjects were correct less than half of the time.
Their guesses were based on patterns they thought they saw.
If they always guessed that the image would show up at the top, they would guess correctly most of the time.
Notable Valid Inferences
The images showed up at the top of the screen over 50% of the time.
A
If the subjects had always guessed that the next image would appear at the top, they would not have been basing their guesses on any pattern they believed they saw in the sequence.
Could be false. It could be that the strategy of always guessing that the images would be at the top came from repeatedly observing the image at the top. In the world where the subjects were always guessing top, we don’t have the information to say what this guess was based on.
B
Basing one’s guesses about what will happen next on the basis of patterns one believes one sees is less likely to lead to correct guesses than always guessing that what has happened before will happen next.
Could be false. (B) compares the strategy that the subjects used (basing guesses on perceived patterns) with a strategy that is not mentioned in the stimulus, so we cannot say which of these strategies is more likely to lead to correct guesses.
C
There was no predictable pattern that one could reasonably believe occurred in the series of images on the computer screen.
Could be false. It could be the case that there was a predictable pattern, but that the subjects didn’t pick up on it quickly enough to guess correctly a majority of the time.
D
Some of the subjects sometimes guessed that the next image would appear at the bottom of the computer screen, but were incorrect.
Must be true. Since subjects guessed correctly less than half of the time but would have been right most of the time by always choosing "top," they must have sometimes guessed "bottom" and been wrong. Otherwise, their accuracy wouldn’t be below 50%.
E
The most rational strategy for guessing correctly where the next image would appear would have been simply to always guess that the image would appear at the top.
Could be false. While we know that always guessing top would be more accurate than the strategy that the subjects used, we don’t know that always guessing top would be the most accurate strategy. There could have been other, more accurate, strategies.
Summary
A chain of service stations charged a $0.25 fee per purchase for fuel paid for with a credit card. This caused the service station’s customers to be angry. Instead, the chain decided to raise the overall price of fuel and offer customers a $0.25 discount for paying with cash. The service station’s customers were happier with this policy.
Strongly Supported Conclusions
Sometimes people’s reactions to a situation depends in part on how that situation is presented to them.
A
People usually adopt beliefs without carefully assessing the evidence for and against those beliefs.
This answer is unsupported. We don’t know from the stimulus under what circumstances people will usually adopt beliefs.
B
People’s perceptions of the fairness of a policy sometimes depend on whether that policy benefits them personally.
This answer is unsupported. We don’t know from the stimulus whether people think this policy is fair. We can’t infer from their happiness that they think it is fair.
C
People usually become emotional when considering financial issues.
This answer is unsupported. We don’t know from the stimulus under what circumstances people usually become emotional.
D
People often change their minds about issues that do not make significant differences to their lives.
This answer is unsupported. We don’t know from the stimulus under what circumstances people change their mind. We don’t even know if the customers who were previously angry are the same customers that are happier after the policy change.
E
People’s evaluations of a situation sometimes depend less on the situation itself than on how it is presented to them.
This answer is strongly supported. The only thing that changed in this scenario was whether or not customers were aware of the surcharge.