Summarize Argument: Phenomenon-Hypothesis
The author hypothesizes that an increase in the North Atlantic harp seal population is unlikely to be responsible for a drop in the cod population over the same time period. The author supports this hypothesis by stating that cod is not a significant part of the seals’ diet. After all, if the seals aren’t eating the cod, how could they be responsible for the observed phenomenon of the cod’s decline?
Notable Assumptions
The author assumes that the only possible way that the seal increase could causally contribute to the cod decrease is that the seals directly eat the cod. This overlooks the possibility that the two phenomena have an indirect causal relationship: for example, the seals might eat a different fish that the cod also rely on, or otherwise impact the ecosystem in a way that harms the cod.
A
People who fish for cod commercially are inconvenienced by the presence of large numbers of seals near traditional fishing grounds.
This does not weaken the argument. If the seals are actually helping to protect the cod by deterring fishers, that does nothing to undermine the author’s hypothesis that the seals aren’t harming the cod population.
B
Water pollution poses a more serious threat to cod than to the harp seal.
This does not weaken the argument. In fact, by providing an alternative hypothesis explaining why the cod population might decline that’s unrelated to the seal population increase, this claim would actually strengthen.
C
The harp seal thrives in water that is too cold to support a dense population of cod.
This does not weaken the argument. If anything, this claim would strengthen: it implies that the seals and the cod live in different parts of the North Atlantic, which makes it less likely that the seals would have an impact on the cod population.
D
Cod feed almost exclusively on capelin, a fish that is a staple of the harp seal’s diet.
This weakens the argument, because it provides an indirect causal mechanism linking the increase in seals and the decline in cod. This rebuts the assumption that the seals must either eat the cod or else not affect them at all, thus undermining the author’s hypothesis.
E
The cod population in the North Atlantic began to decline before the harp-seal population began to increase.
This does not weaken the argument. This claim still doesn’t indicate whatsoever that the seal increase might contribute to the cod decrease. If anything, it strengthens the argument by indicating that the cod decline began independently of the seal increase.
Summarize Argument
The author concludes that dentists shouldn’t fill cavities unless the nerves inside the tooth are in imminent danger from the cavity. This is because filling cavities damages healthy parts of the tooth, and cavities are only dangerous if the nerves are damaged.
Notable Assumptions
The author assumes that cavities don’t develop quickly from one state to another. Were a cavity to develop quickly from a seemingly benign state to a dangerous one, then a filling would’ve been beneficial. Alternately, she assumes dentists can assume which cavities will develop to a dangerous state. The author also assumes that it’s preferable to avoid guaranteed harm (filling a cavity) when the other option is potential harm (nerve damage).
A
Dentists should perform any procedure that is likely to be beneficial in the long term, but only if the procedure does not cause immediate damage.
We’re talking about what dentists shouldn’t do. Since most cavities don’t progress to a dangerous state, they shouldn’t perform fillings on the basis of decay that may happen in the future.
B
Dentists should help their patients to prevent cavities rather than waiting until cavities are present to begin treatment.
The author doesn’t say dentists should be more proactive. This is about when filling should be performed.
C
A condition that is only potentially harmful should not be treated using a method that is definitely harmful.
Fillings are a certain harm. Cavities are a potential harm. It’s better to see what happens with the cavity rather than causing certain harm with the filling.
D
A condition that is typically progressive should not be treated using methods that provide only temporary relief.
Irrelevant. Fillings don’t provide temporary relief.
E
A condition that is potentially harmful should not be left untreated unless it can be kept under constant surveillance.
The author says that cavities should be left untreated for the most part. This tells us the opposite.
Summarize Argument
The author argues that the student in question will likely get a B in their upcoming course. This is because she has received Bs in the majority of the 12 other courses she’s taken.
Notable Assumptions
The author assumes that the student receiving Bs in most of her courses makes it likely she’ll receive a B in this course. That means that the author doesn’t believe the student has improved or improved as a student, and that this course doesn’t significantly differ from the majority of her courses in any meaningful way.
A
The student previously studied alone but is receiving help from several outstanding students during the present course.
Since the student is changing her study strategy, it seems very likely her grade will improve. This seems to severely damage the author’s conclusion.
B
The twelve courses together covered a broad range of subject matter.
The student didn’t struggle or succeed in one specific area. She got Bs in virtually everything, so there’s no reason to believe this course would be any different.
C
The student previously studied in the library and continues to do so.
The student hasn’t changed this one aspect of her study habits. Thus, we can’t assume she’s improved or gotten worse.
D
The student received a B in all but one of the twelve courses.
This intensifies “majority” to “vast majority.” The student in question is decidedly a B student.
E
The current course is a continuation of one of the twelve courses in which the student received a B.
Since the student got a B in the first course, we can conclude the subject matter in the new course isn’t particularly to her favor (or not to her favor).