Summarize Argument: Counter-Position
The fact that, in a few centuries, there will be ten people for every square meter will only be temporarily solved by humans learning how to colonize other planets. Colonizing other planets will only temporarily solve Earth’s population crisis because if the population keeps doubling every 30 years, and half of Earth's population moves to Mars in 2500, Earth will be just as crowded as before by 2530.
Identify Conclusion
The conclusion is the essayist’s criticism of a potential solution to the fact that Earth’s population may soon grow to where there are ten people for every square meter of Earth’s surface. The essayist disputes the claim that colonizing other planets will be a solution for Earth’s overpopulation. The essayist’s conclusion is that this potential solution is flawed because colonizing other planets will only "be a temporary solution at best."
A
If Earth’s population continues to grow geometrically, then in a few centuries the population density of Earth’s surface will be ten people per square meter.
This is context. The essayist explains how Earth’s population is growing to introduce a possible solution—colonizing other planets. This context helps us understand the essayist’s main point: colonizing other planets won’t solve overpopulation in the long term, only temporarily.
B
Due to the continuing geometric growth of Earth’s population, the problem of overpopulation of Earth will probably persist.
The essayist doesn’t make this claim. The essayist argues that if Earth's population keeps growing, one proposed solution may not be enough. However, the essayist doesn’t say for sure that Earth's population will grow this way or that overpopulation will “probably” be a problem.
C
If Earth’s population continues to double every 30 years, and if at some point half of the population of Earth emigrated elsewhere, then after 30 years Earth would be just as crowded as it had been before the emigration.
This is a premise. The fact that Earth will be just as crowded again after half the population moves to another planet supports the main conclusion that colonizing other planets is only a temporary fix for overpopulation. It explains why this solution won’t help in the long term.
D
The population of Earth’s surface will probably continue to grow geometrically even if temporary solutions to population growth, such as colonizing other planets, are adopted.
This is an assumption the essayist makes. The essayist assumes that Earth's population will keep doubling, even after some people hypothetically move to Mars. If this assumption is true, the essayist argues that colonizing other planets will only temporarily fix overpopulation.
E
Learning how to colonize other planets would, at best, be a temporary solution to the overcrowding of Earth.
This accurately states the main conclusion. The essayist disagrees that colonizing other planets will solve Earth's future overpopulation, believing it would only be a temporary solution for such overcrowding because the growing population will eventually replace those who leave.
Summarize Argument: Phenomenon-Hypothesis
The author hypothesizes that the complexity of chocolate probably masks differences in taste between full-fat and low-fat chocolate ice cream. This is based on the fact that in a taste test, most people like low-fat chocolate ice cream as much as full-fat versions. But with vanilla ice cream, people tend to dislike the taste of low-fat versions compared ot full-fat versions. In addition, chocolate is known to be a very complex flavor.
Notable Assumptions
The author assumes that there’s no other explanation besides complexity of flavor for the differing reactions between low-fat chocolate and low-fat vanilla. The author also assumes that vanilla is not as complex a flavor as chocolate.
A
Most people prefer full-fat chocolate ice cream to full-fat vanilla ice cream.
Whether more people like chocolate vs. vanilla is not at issue. The issue is what explains why people like low-fat vs. full-fat chocolate equally, whereas they like full-fat vanilla more than low-fat vanilla.
B
The subjects of the previous tests were not informed of the difference in fat content.
Whether the subjects in previous tests knew about the fat differences has no clear impact on what explains why people like low-fat and full-fat chocolate ice cream equally.
C
The more distinct compounds required to produce a flavor, the better people like it.
This suggests a more complex flavor will be more liked than a less complex flavor. But we’re concerned with comparisons between high-fat and low-fat within the same flavor. Why do people like low-fat vanilla less than high-fat vanilla, but like both versions of chocolate equally?
D
Vanilla is known to be a significantly less complex flavor than chocolate.
If vanilla were just as complex as chocolate, the author’s hypothesis about complexity masking taste wouldn’t make sense, because people dislike low-fat vanilla compared to high-fat. (D) defends the argument by confirming that vanilla is less complex than chocolate.
E
Most people are aware of the chemical complexities of different flavors.
People’s awareness of complexities of flavors has no clear impact. They may be aware, but we have no reason to think this relates to complexity of flavor helping to mask taste differences between high-fat and low-fat ice creams.
Summarize Argument
The author concludes that life may be able to arise under difficult conditions throughout the universe. This is based on the finding of fossilized bacteria in 3.5 billion-year-old rocks. Since these bacteria were already complex, the author draws a subsidiary conclusion that the bacteria had a long evolutionary history by the time they were fossilized. Since Earth is only 4.6 billion years old, the author believes the bacteria must have appeared shortly after the Earth was formed, when conditions were difficult. This is why the author believes live might be able to arise under difficult conditions.
Identify Argument Part
The referenced text is a subsidiary conclusion.
A
It is a claim for which no support is provided in the argument, and that is used to illustrate the conclusion of the argument as a whole.
The referenced text has support from the claim that the bacteria were quite complex.
B
It is a claim for which no support is provided in the argument, and that is used to support a claim that in turn lends support to the conclusion of the argument as a whole.
The referenced text has support from the claim that the bacteria were quite complex.
C
It is a claim for which some support is provided in the argument, and that itself is used to support another claim that in turn lends support to the conclusion of the argument as a whole.
This accurately describes the role of the referenced text. It’s a subsidiary conclusion.
D
It is a claim for which some support is provided in the argument, and that itself is not used to support any other claim in the argument.
The referenced text is used to support the claim that the first life on Earth must have appeared soon after the planet’s formation.
E
It is a claim for which some support is provided in the argument, and that itself is used to support two distinct conclusions, neither of which is intended to provide support for the other.
The referenced text does not support two distinct, unrelated conclusions. It supports the claim that the first life on Earth must have appeared soon after the planet’s formation. This claim in turn supports the last sentence. But these conclusion are not unrelated.
Summarize Argument: Counter-Position
The author concludes that exact replication is not the only quality viewers value in a painting. He supports this by contending that, if this wasn’t the case, photography would have replaced painting as an art form by now.
Describe Method of Reasoning
The author is supporting a conclusion about people’s preferences in visual art by citing a relevant fact. Note that this is an “is” conclusion, not an “ought” conclusion: the author is talking about what people do like, not what they should like.
A
using a claim about what most people appreciate to support an aesthetic principle
The author’s claim about what people appreciate (i.e. paintings that aren’t exact replicas) is his conclusion; it doesn’t support anything else. Also, it’s not clear that his claims are necessarily about “most” people.
B
appealing to an aesthetic principle to defend the tastes that people have
The author doesn’t defend people’s tastes: he simply describes them.
C
explaining a historical fact in terms of the artistic preferences of people
This gets it backwards: the historical fact (that photography didn’t displace painting) is used to make a conclusion about people’s artistic preferences (more than just replication).
D
appealing to a historical fact to support a claim about people’s artistic preferences
The author cites a historical fact (that photography didn’t displace painting) to justify his claim that people desire more than pure replication in paintings.
E
considering historical context to defend the artistic preferences of people
The author doesn’t defend people’s tastes: he simply describes them. The historical context is used to show what the preferences are, not to defend them.