Specially bred aquarium fish with brilliant coloration and unusual body shapes may be popular with connoisseurs, but they are inferior to ordinary fish. Hampered by their elaborate tails or strangely shaped fins, the specially bred fish cannot reach food as quickly as can the ordinary fish that compete with them for food, and so they are often underfed. Also, they do not breed true; most offspring of the specially bred fish lack the elaborate tails and brilliant coloration of their parents.

Summary
Specially bred aquarium fish with bright colors and unusual shapes may be popular with collectors, but they are inferior to ordinary fish. Their fancy tails and strangely shaped fins make it harder for them to get food as quickly as ordinary fish, so they are often underfed. Also, their offspring usually don’t have the same fancy tails or bright colors as their parents.

Strongly Supported Conclusions
In some cases, an animal’s aesthetic appeal may lead to physical disadvantages.
Since many specially bred aquarium fish do not pass their traits to their offspring, their value might diminish overtime for those collectors who hope to breed them.
The fancy tails and strangely shaped fins of specially bred aquarium fish allow them to be outcompeted for food by ordinary fish, which tend not to have fancy tails and strangely shaped fins.

A
Specially bred aquarium fish must receive special care if they are to survive.
Unsupported. Specially bred aquarium fish may often be underfed, but we do not know that this means they will not survive. Perhaps they are underfed but are still able to survive without any special care.
B
Connoisseurs are not interested in dull-colored, simply shaped fish.
Unsupported. Specially bred aquarium fish may be popular with connoisseurs, but this does not mean that those connoisseurs are not interested in dull-colored, simply shaped fish.
C
Most specially bred aquarium fish are purchased by connoisseurs.
Unsupported. Specially bred aquarium fish may be popular with connoisseurs, but we do not know whether most specially bred aquarium fish are purchased by connoisseurs.
D
Ordinary fish tend not to have elaborate tails or strangely shaped fins.
Strongly supported. The elaborate tails and strangely shaped fins of specially bred aquarium fish are the reason that they are outcompeted for food by ordinary fish. Thus, ordinary fish must tend not to have elaborate tails or strangely shaped fins.
E
Strangely shaped fins and elaborate tails interfere with a fish’s ability to reproduce.
Unsupported. Strangely shaped fins and elaborate tails interfere with specially bred aquarium fish’s ability to get food quickly. We do not know that these things interfere with their ability to reproduce.

7 comments

Sartore is a better movie reviewer than Kelly. A movie review should help readers determine whether or not they are apt to enjoy the movie, and a person who is likely to enjoy a particular movie is much more likely to realize this by reading a review by Sartore than a review by Kelly, even though Sartore is more likely to give a movie an unfavorable review than a favorable one.

Summarize Argument

The author argues that Sartore is a better movie reviewer than Kelly. The author supports this by asserting that a quality of good movie reviewers is helping readers determine whether or not they will enjoy the movie. What’s more, Sartore fulfils this quality better than Kelly does because Sartore’s reviews are more likely than Kelly’s to make a reader realize what movies they will probably enjoy.

Notable Assumptions

The author assumes that helping readers to determine whether they will enjoy a movie or not is the most important thing that movie reviews should do.

The author also assumes that a person who is likely not to enjoy a movie is equally or more likely to realize this by reading a review by Sartore compared to a review by Kelly.

A
Sartore has technical knowledge of film, whereas Kelly is merely a fan.

This doesn’t strengthen, since the argument only defines a good movie reviewer based on the outcome of their reviews, i.e. helping readers determine which movies they will or won’t like. The background of the movie reviewers is irrelevant.

B
Most of Kelly’s movie reviews are unfavorable to the movie being reviewed.

It’s irrelevant to the argument whether most of the reviews of either critic are positive or negative, as long as the reviews fulfil the criterion of helping readers determine whether or not they will enjoy the movie.

C
One who is apt not to enjoy a particular movie is more likely to realize this by reading a review by Sartore than a review by Kelly.

This strengthens the argument by affirming the assumption that Sartore helps more people than Kelly not just with determining which movies they will enjoy, but also which movies they won’t enjoy.

D
Reading a movie review by Sartore will usually help one to enjoy the movie more than one otherwise would have.

This does not strengthen, because the author never claims that a movie review changing the reader’s enjoyment of the movie influences whether the review is good or not.

E
Most of the movies that Sartore reviews are also reviewed by Kelly.

This is irrelevant, as the argument only compares Sartore and Kelly based on whether their reviews of a given movie will be more likely to help a reader determine whether they would enjoy that movie. It doesn’t matter how much overlap there is between the movies they review.


34 comments

Modest amounts of exercise can produce a dramatic improvement in cardiovascular health. One should exercise most days of the week, but one need only do the equivalent of half an hour of brisk walking on those days to obtain cardiovascular health benefits. More vigorous exercise is more effective, but a strenuous workout is not absolutely necessary.

Summary

Modest amounts of exercise can greatly improve heart health. You should exercise most days, but the equivalent of just 30 minutes of brisk walking on those days is enough to see benefits. More intense exercise works better, but a hard workout isn’t required.

Strongly Supported Conclusions

Because they’re more effective than modest exercise, strenuous workouts most days of the week can also dramatically improve heart health.

Improving heart health does not require strenuous exercise or time-consuming workouts.

A
Having a strenuous workout most days of the week can produce a dramatic improvement in cardiovascular health.

Strongly supported. Modest amounts of exercise most days of the week can dramatically improve heart health. Strenuous exercise is more effective than modest exercise. So, having a strenuous workout most days of the week can dramatically improve heart health.

B
Doing the equivalent of an hour of brisk walking two or three times a week generally produces dramatic improvements in cardiovascular health.

Unsupported. We’re told that doing the equivalent of 30 minutes of brisk walking most days of the week (at least 4 days) can improve heart health. We don’t know that doing the equivalent of an hour of brisk walking 2-3 times a week could produce the same improvements.

C
It is possible to obtain at least as great an improvement in cardiovascular health from doing the equivalent of half an hour of brisk walking most days of the week as from having a strenuous workout most days of the week.

Anti-supported. We’re told that strenuous exercise is more effective than modest exercise. So we cannot conclude that it’s possible to obtain at least as great an improvement in heart health from modest exercise as from strenuous exercise.

D
Aside from exercise, there is no way of improving one’s cardiovascular health.

Unsupported. We know that exercise can improve cardiovascular health, but we do not know that it’s the only way to improve cardiovascular health.

E
To obtain a dramatic improvement in one’s cardiovascular health, one must exercise strenuously at least occasionally.

Anti-supported. We’re told that modest amounts of exercise can produce a dramatic improvement in cardiovascular health and that although more vigorous exercise is more effective, “a strenuous workout is not absolutely necessary.”


31 comments

Anthropologist: In an experiment, two groups of undergraduates were taught how to create one of the types of stone tools that the Neanderthals made in prehistoric times. One group was taught using both demonstrations and elaborate verbal explanations, whereas the other group learned by silent example alone. The two groups showed a significant difference neither in the speed with which they acquired the toolmaking skills nor in the level of proficiency they reached. This shows that Neanderthals could just as well have created their sophisticated tools even if they had no language.

Summarize Argument
The anthropologist concludes that Neanderthals could’ve created tools without language. She bases this on a study showing that university students were as capable of making one type of prehistoric stone tool when they learned by silent example as when they learned by verbal instruction.

Notable Assumptions
The anthropologist assumes that the stone tools Neanderthals made were no more sophisticated than those that the undergraduates made. If the Neanderthals consistently made far more sophisticated tools, then no conclusion can be drawn from the study about whether or not language was necessary for Neanderthal tool-building.

A
Apart from the sophistication of their stone tools, there is a great deal of evidence suggesting that Neanderthals possessed some form of language.
We don’t care about evidence that tells us Neanderthals had language. We’re interested in whether their tools prove they must’ve had language.
B
The students who were taught with verbal explanations were allowed to discuss the toolmaking techniques among themselves, whereas the students who learned by silent example were not.
Both groups created the same tools. This doesn’t further differentiate them in any meaningful way.
C
The tools that the undergraduates were taught to make were much simpler and easier to make than most types of tools created by Neanderthals.
Sure, simple tools can be made without language. But Neanderthals also made many types of sophisticated tools. We don’t know if they needed language to make those.
D
The instructor who taught the group of students who learned by silent example alone was much less proficient at making the stone tools than was the instructor who taught the other group of students.
Like (B), both groups created the same tools. This doesn’t further differentiate them in any meaningful way.
E
The tools created by Neanderthals were much less sophisticated than the tools created by anatomically modern humans who almost certainly possessed language and lived at the same time as the Neanderthals.
We don’t care about other humanoids. We need to know whether we can draw conclusions about Neanderthals and language based on the tools they made.

6 comments