Summarize Argument: Phenomenon-Hypothesis
The author concludes that eating lots of fat, processed sugar, or alcohol, can contribute to heart disease. This is based on the fact that these things increase blood triglyceride levels, and the hypothesis that higher blood triglyceride increases the risk of heart disease. This hypothesis is based on research that shows a correlation between blood triglyceride levels above 1 milligram per millileter and higher likelihood of heart attacks.
Notable Assumptions
The author assumes that there’s no other explanation for the correlation observed betwen blood triglyceride levels and heart attacks. The author also assumes that there aren’t other things in fat, processed sugar, and alcohol that tend to decrease the risk of heart attacks.
A
People with a high-fat diet who engage in regular, vigorous physical activity are much less likely to develop heart disease than are sedentary people with a low-fat diet.
This suggests physical activity is also a causal factor in heart disease. But this doesn’t suggest high fat consumption isn’t also a causal factor. (A) could have been correct if we knew that people with high blood triglyceride on average exercise a less than others.
B
Triglyceride levels above 2 milligrams per milliliter increase the risk of some serious illnesses not related to heart disease.
Other diseases aren’t relevant to whether triglyceride levels are a causal factor in heart disease.
C
Shortly after a person ceases to regularly consume alcohol and processed sugar, that person’s triglyceride levels drop dramatically.
This strengthens the connection between consumption of alcohol/sugar and triglyceride. This is consistent with the author’s reasoning.
D
Heart disease interferes with the body’s ability to metabolize triglycerides.
This suggests an alternate explanation for the correlation between higher blood triglyceride levels and heart attacks. If heart disease interferes with triglyceride metabolization, it would lead to higher blood triglyceride. This suggests the cause and effect could be reversed.
E
People who maintain strict regimens for their health tend to adopt low-fat diets and to avoid alcohol and processed sugar.
This has no impact, because we don’t know whether the people on these low-fat and low-sugar diets are more or less likely than others to have heart attacks.
Summarize Argument: Counter-Position
Some historians conclude that recipes compiled by Apicius are a reliable indicator of how wealthy Romans made their food. The author’s conclusion is that the historian’s conclusion isn’t necessarily true. This is because only a few other recipes from Apicius’s time have survived, and Apicius’s recipes may be unrepresentative of ancient Roman food. The author also relies on an analogy to many modern chefs; just as their recipes are unusual, so too might be Apicius’s.
Describe Method of Reasoning
The author criticizes the historian’s conclusion by pointing out that it might be based on an unrepresentative sample of recipes. The author also relies on an analogy to support the possibility that the sample is unrepresentative.
A
It rejects a view held by some food historians solely on the grounds that there is insufficient evidence to support it.
Calling a conclusion “too hasty” is not the same as rejecting it. The author doesn’t necessarily believe the historians are wrong; he’s simply pointing out they might be wrong. Also, the author relies on an analogy; not “solely” on the claim that there’s insufficient evidence.
B
It offers support for a view held by some food historians by providing a modern analogue to that view.
The author does not support the historians’ view. He points out that there are reasons to think it might not be true.
C
It takes issue with the view of some food historians by providing a modern analogue that purportedly undercuts their view.
The author takes issue with the view of the historians (”the conclusion is too hasty”) by providing a modern analogue (”many notable modern chefs”) that purportedly undercuts the historians’ view (suggesting that Apicius’s recipes might be unrepresentative).
D
It uses a conclusion drawn by some food historians as the basis for a conclusion about a modern analogue.
The author’s conclusion is not about the modern chefs. The modern chefs are used as support for the conclusion that the historian’s conclusion is too hasty.
E
It tries to bolster a conclusion about the similarity of historical times to modern times by comparing a conclusion drawn by some food historians to a modern analogue.
The conclusion is not about the “similarity of historical times to modern times.” The author uses an analogy to modern chefs to conclude that we do not necessarily know that Apicius’s recipes are representative of the food of wealthy ancient Romans.
Music historian: In the past, radio stations would not play rock songs that were more than three minutes in length. Rock musicians claimed that such commercial barriers limited their creativity, and some critics argue that only since those barriers have been lifted has rock music become artistic. In fact, however, when these barriers were lifted, the standards for song structures broke down and the music became aimless, because the styles from which rock derived were not well suited to songs of extended length.
Summary
Usually, radio stations do not play rock songs longer than three minutes. Rock musicians argue that this time constraint limited their creativity, and some critics argue that rock music has become artistic only because this time constraints have been lifted. However, song structures began to break down and music became aimless when the time constraints were lifted. This is because the styles that are the basis of rock music are not well suited for songs of extended length.
Strongly Supported Conclusions
In some cases, rock music can benefit from time constraints rather than be harmed by them.
A
Rock music is not a good outlet for creative musicians who have a great many ideas.
This answer is unsupported. To say that rock music is not a good outlet for creativity is too extreme. We only know rock musicians argue that time constraints limit creativity, not eliminate creativity entirely.
B
Rock music must borrow from styles more conducive to songs of extended length if it is to become artistic.
This answer is unsupported. To say that rock music must borrow from other styles is too extreme. We don’t know from the stimulus if there are any styles that are suited for songs of extended length.
C
Rock music requires more discipline than some other forms of music.
This answer is unsupported. We are not told anything about other forms of music in order to make this comparison.
D
Rock music can sometimes benefit from the existence of commercial barriers rather than being harmed by them.
This answer is strongly supported. We know from the stimulus that, after time constraints were lifted, song structures began to break down. Therefore, rock music benefited at least somewhat from the time constraints.
E
Rock music is best when it is made by musicians who do not think of themselves as being self-conscious artists.
This answer is unsupported. We don’t know from the stimulus under what circumstances rock music is the best.
Summary
The author concludes that a recently discovered fossil does not provide evidence that birds evolved from dinosaurs. Why? Because of the following:
In order for a fossil to serve as evidence that birds evolved from dinosaurs, it must be the case that the entire fossil is from a single animal.
But the recently discovered fossil is a compositive of bones collected from different parts of the discovery site.
In order for a fossil to serve as evidence that birds evolved from dinosaurs, it must be the case that the entire fossil is from a single animal.
But the recently discovered fossil is a compositive of bones collected from different parts of the discovery site.
Missing Connection
We know from the first premise that if the fossil isn’t from a single animal, then it isn’t evidence that birds evolved from dinosaurs. But do we have enough to establish that the fossil isn’t from a single animal? No — all we know from the other premise is that the fossil is a composite of bones from different parts of the discovery site. But couldn’t the bones still be from the same animal?
To make the argument valid, then, we want to prove that the fossil is not from the same animal. We can do this by establishing that if the fossil is a composite from different areas of the discovery site, it must come from more than one animal.
To make the argument valid, then, we want to prove that the fossil is not from the same animal. We can do this by establishing that if the fossil is a composite from different areas of the discovery site, it must come from more than one animal.
A
The only paleontologists who believe that the entire fossil is from a single animal are those who were already convinced that birds evolved from dinosaurs.
(A) doesn’t establish that the fossil comes from multiple animals. What scientists believe about the fossil doesn’t establish that it comes from multiple animals.
B
If the fossil is a composite, then it has pieces of more than one animal.
We know from a premise that the fossil is a composite. According to (B), then, it has pieces of more than one animal. Since the fossil isn’t just from a single animal, we can conclude that the fossil cannot serve as evidence that birds evolved from dinosaurs.
C
There are other fossils that provide evidence that birds evolved from dinosaurs.
(C) doesn’t establish that the fossil comes from multiple animals. What is true about other fossils doesn’t prove the origin of this fossil.
D
If the entire fossil is from a single animal, then it is a well-preserved specimen.
We don’t know that the fossil is NOT a well-preserved specimen. So (D) doesn’t establish that the fossil comes from multiple animals.
E
The fossil was stolen from the discovery site and sold by someone who cared much more about personal profit than about the accuracy of the fossil record.
(E) doesn’t establish that the fossil comes from multiple animals.