(D) points out that there is a distinction between being stupid and being deceitful.
For example, say we know that "X is a banana" and we know that "all bananas are fruits". Does it follow that X is a fruit? Of course it does. Simple logic. But, does it follow that we should know that X is a fruit? Well, that depends on a lot of circumstances. Are we 15 months old? If that's the case, then probably not. Are we 15 years old with normal brain function? If so, then probably yes.
(D) is simply saying that when the witness said that "X is not a fruit" it could be that he's lying or it could be that he's stupid (or that he's a 15 month old baby, but now I'm being redundant).
Witness: Yes.
Lawyer: And the best writer?
Witness: Yes.
Lawyer: In fact everyone she assigned to work on the project was top notch?
Witness: That’s true.
Lawyer: So, you lied to the court when you said, earlier, that Congleton wanted the project to fail?
Summarize Argument
The lawyer’s implicit conclusion is that the witness lied when he said that Congleton wanted the project to fail. This is based on the fact that everyone Congleton assigned to the project was excellent.
Identify and Describe Flaw
The author overlooks the possibility that Congleton did not know that the people assigned were excellent.
The author overlooks the possibility that Congleton may have wanted the project to fail despite assigning only excellent people to it.
The author assumes that Congleton had the ability to choose other people for the project.
The author assumes that the witness believed Congleton did not want the project to fail when the witness said that Congleton did want the project to fail.
A
It takes for granted that Congleton was not forced to assign the people she did to the project.
If Congleton had been forced to assign those people to the project, that shows we cannot infer anything about Congleton’s state of mind or purpose from that assignment. So, (A) must be assumed.
B
It takes for granted that the project could fail only if Congleton wanted it to fail.
Whether the project actually can or will fail is irrelevant. The argument concerns only whether Congleton wanted the project to fail and whether her hiring decisions indicate that desire.
C
It ignores the possibility that Congleton knew that the people assigned to the project would not work well together.
If Congleton knew that the people assigned wouldn’t work well together, that could show how she could have thought her assignments would not produce good results, despite the individual excellence of each employee.
D
It ignores the possibility that the witness failed to infer from known facts what should have been inferred and therefore was not lying.
If this possibility were true, then the witness was not necessarily lying when he said what he said about Congleton. So, this possibility would undermine the argument.
E
It ignores the possibility that Congleton failed to allot enough time or resources to the project team.
If this possibility were true, this shows how she could have thought her assignments would not produce good results, despite the individual excellence of each employee.
(D) points out that there is a distinction between being stupid and being deceitful.
For example, say we know that "X is a banana" and we know that "all bananas are fruits". Does it follow that X is a fruit? Of course it does. Simple logic. But, does it follow that we should know that X is a fruit? Well, that depends on a lot of circumstances. Are we 15 months old? If that's the case, then probably not. Are we 15 years old with normal brain function? If so, then probably yes.
(D) is simply saying that when the witness said that "X is not a fruit" it could be that he's lying or it could be that he's stupid (or that he's a 15 month old baby, but now I'm being redundant).
Summarize Argument
The researcher concludes the study does not support recommending North Americans eat fewer calories to extend their lives. Why not? Because unnaturally calorific laboratory diets are the reason a reduced-calorie diet increased longevity in the study.
Notable Assumptions
The researcher assumes that North Americans’ diets are more in line with their natural calorie intake than the diets of laboratory animals. Furthermore, she assumes the animals studied had a pre-diet calorie intake typical for laboratory animals.
A
North Americans, on average, consume a higher number of calories than the optimal number of calories for a human diet.
This challenges the assumption that the laboratory animals’ unnaturally high calorie intake makes them dissimilar from North Americans. If North Americans consume more calories than optimal, then they are similar to laboratory animals in that way, not different.
B
North Americans with high-fat, low-calorie diets generally have a shorter life expectancy than North Americans with low-fat, low-calorie diets.
This relationship between fat intake and life expectancy does not imply that the study’s findings can be correctly extended to North Americans. The researcher does not say fat intake was examined separately from calorie intake.
C
Not all scientific results that have important implications for human health are based on studies of laboratory animals.
This states that some studies with implications for human health do not involve laboratory animals, not that studies of laboratory animals must or usually have implications for human health.
D
Some North Americans who follow reduced-calorie diets are long-lived.
This does not say North Americans who eat fewer calories are tend to live longer—it’s possible North Americans on normal diets are more likely to be long-lived than those on reduced-calorie diets.
E
There is a strong correlation between diet and longevity in some species of animals.
This does not specify which type of diet increases longevity or identify the species in question. This may support doctors making some dietary recommendation to increase longevity, but not the one described on the basis of the study.
Summarize Argument
The author concludes that no wealthy person should be on the Grandville Planning Committee because some wealthy Grandville citizens have been criminals, and the committee must only include people with unquestionable personal ethics.
Identify and Describe Flaw
This is the cookie-cutter flaw of hasty generalization, where The author makes a broad generalization about an entire group based on evidence about only some members of that group. He assumes that, just because some wealthy Grandville citizens have been criminals, no wealthy person should be on the committee.
A
confuses a result with something that is sufficient for bringing about that result
The author simply doesn’t make this mistake. He never addresses the result of appointing wealthy people or criminals to the committee at all.
B
mistakes a temporal relationship for a causal relationship
The author doesn't do this. His argument doesn't address a temporal or a causal relationship between anything. That is, he doesn’t say what caused some wealthy people to be criminals or what might happen if they are appointed to the committee.
C
assumes that because a certain action has a certain result the person taking that action intended that result
Like (A), the author never addresses the results of appointing wealthy people or criminals to the committee at all. He also never mentions anyone’s intentions.
D
judges only by subjective standards something that can be readily evaluated according to objective standards
The claim that some wealthy citizens are criminals is objective. However, the claims about who should be appointed to the committee are somewhat subjective; they can’t readily be evaluated objectively. So, the author doesn’t make this mistake.
E
generalizes on the basis of what could be exceptional cases
The author broadly generalizes about all wealthy Grandville citizens based on evidence about only some of them. Those wealthy Grandville citizens who are criminals could be exceptional cases; that is, there may be only a few of them.
Hampton: You are overlooking the promise of technology. I am confident that improvements in agriculture will allow us to feed the world population of ten billion predicted for 2050 without significantly increasing the percentage of the world’s land now devoted to agriculture.
Speaker 1 Summary
Kim claims that the growing world population is threatening nature by causing increased demand for food production. To support the idea that there’s a threat, Kim explains that the demands of a larger population will require more land use, thereby reducing the land available to wildlife.
Speaker 2 Summary
Hampton believes that the harm to nature won’t be as bad as Kim thinks. This conclusion isn’t stated, but is implied by Hampton’s claims that Kim is overlooking the impact of technology, and that technology will allow farmers to produce enough food without using more land.
Objective
We need to find an agreement between Kim and Hampton. They agree that the world population is growing and will need more food, and seem to agree about the general goal of protecting nature.
A
Efforts should be taken to slow the rate of human population growth and to increase the amount of land committed to agriculture.
Neither speaker makes either of these claims. Firstly, no one brings up the idea of slowing population growth. Secondly, both Kim and Hampton are favorable to limiting the amount of land used for agriculture, not increasing it.
B
Continued research into more-efficient agricultural practices and innovative biotechnology aimed at producing more food on less land would be beneficial.
Kim would agree with this in order to limit the harm population growth will cause to nature. Hampton would also agree, as shown by the use of words like “promise” and “improvement” to discuss these advancements in a positive light. This is a point of agreement.
C
Agricultural and wilderness areas need to be protected from urban encroachment by preparing urban areas for greater population density.
Neither speaker discusses increasing the density of urban areas; nor do either of them talk about protecting agricultural land from urban sprawl.
D
In the next half century, human population growth will continue to erode wildlife habitats and diminish forests.
Kim can reasonably be said to agree with this. However, Hampton does not necessarily agree: Hampton claims that increased food production likely won’t erode habitats or forests, and doesn’t talk about any other factor that would.
E
The human diet needs to be modified in the next half century because of the depletion of our natural resources due to overpopulation.
Neither speaker talks about modifying human diets. Additionally, although Kim is concerned about a threat to natural resources, neither Kim nor Hampton talks about a total depletion of resources.