Sign up to star your favorites LSAT 140 - Section 2 - Question 03
November 17, 2013
Summarize Argument
The author concludes that humorous ads are the only effective ones. He supports this with the following premises:
(1) If something is humorous, it will attract people’s attention and allow a message to be conveyed.
(2) If an ad is effective, it must convey its message.
(1) If something is humorous, it will attract people’s attention and allow a message to be conveyed.
(2) If an ad is effective, it must convey its message.
Identify and Describe Flaw
This is the cookie-cutter flaw of confusing necessary and sufficient conditions. We know effective ads convey a message (and so they also can convey a message) but the author then assumes that they must be humorous. In other words, he treats “humorous” as necessary for “can convey” when it’s really only sufficient.
He argues that if an ad is effective, it must be humorous, since humorous ads can convey a message. But what if other ads, like emotional ads, can also convey a message? In that case, humorous ads might not be the only effective ones.
A
It takes for granted that nothing but humor can attract a person’s attention and hold it long enough for a message to be conveyed.
The author treats “humorous” as necessary for “can convey,” when it’s really only sufficient. He assumes that only humor can convey a message. But if scary or sad ads can also hold attention long enough to convey a message, then funny ads might not be the only effective ones.
B
It confuses attracting a person’s attention with holding a person’s attention long enough for a message to be conveyed.
The author actually distinguishes between these ideas by saying that if something is humorous it will not only attract attention but it will also hold attention long enough for a message to be conveyed.
C
It treats a necessary condition for an advertisement’s being effective as if it were a sufficient condition.
The author treats a sufficient condition for “can convey” as if it were a necessary condition. His conclusion isn’t about what is sufficient for an ad’s being effective; it’s about what is necessary for an ad’s being effective.
D
It uses two senses of the term “effective” without differentiating them.
This is the cookie-cutter flaw of equivocation, where the argument uses the same term in different ways. The author doesn't make this mistake; he uses “effective” clearly and consistently throughout his argument.
E
It takes for granted that an advertisement’s only purpose is to convey its message.
The author doesn’t assume this. In fact, he doesn’t make any claims about the purpose of ads at all. Instead, he assumes that humorous ads are the only effective ones, without considering that other kinds of ads might also be able to convey a message and be effective.
Sign up to star your favorites LSAT 140 - Section 2 - Question 04
November 17, 2013
Summarize Argument: Phenomenon-Hypothesis
The author concludes that we don’t need to be concerned by reports of people developing health problems shortly after receiving vaccinations. This is because there are a lot of people who get vaccinated every year, and we would naturally expect some of them to develop health problems by coincidence shortly after getting vaccinated.
Notable Assumptions
The author assumes that the rate of developing health problems isn’t higher shortly after getting vaccinated than it is before getting vaccinated.
A
For the most part, stories of people developing serious health problems shortly after receiving vaccinations involve vaccines that were recently introduced.
If anything, this might undermine the argument by showing that certain vaccines are more associated with health problems than others. That could suggest something besides coincidence accounts for the health problems with these newer vaccines.
B
Some of the illnesses that vaccines are designed to prevent have become so rare that even if people are not vaccinated, they are unlikely to contract those illnesses.
This questions the need for getting a vaccine. But this doesn’t help suggest that vaccines aren’t causing health problems.
C
People are no more likely, on average, to develop serious health problems shortly after receiving vaccinations than shortly before receiving vaccinations.
This shows there’s no correlation between vaccines and higher rates of health problems in the period shortly after vaccinations. If vaccines really did cause the health problems, we’d expect an increase in the rate of health problems shortly after vaccination.
D
The health problems that some people have developed shortly after receiving vaccinations have been more serious than the health problems that the vaccines were intended to prevent.
The comparative severity of health problems after a vaccine and problems the vaccine is designed to prevent is irrelevant. This issue relates to whether one should take the vaccine. But it doesn’t help suggest the vaccine doesn’t cause health problems.
E
In a few cases in which people developed serious health problems shortly after taking other medications, these problems were initially attributed to coincidence but were later determined to be due to the medications.
If anything, this suggests that we should be open to a causal connection between vaccines and the health problems. But we’re trying to support the claim that vaccines are not likely to be the cause of the health problems people develop after vaccination.
Sign up to star your favorites LSAT 140 - Section 2 - Question 05
November 17, 2013Chad: Stray cats are not only a nuisance, they spread diseases and cause injuries to other cats and to humans. People feed these animals out of kindness, but doing so only exacerbates the problem unless the cats are then captured and adopted.
Speaker 1 Summary
Sharita concludes that anyone who owns a cat should have it sprayed or neutered unless they are willing to take care of the cat’s offspring. This is because failure to spay or neuter leads to a lot of stray cats.
Speaker 2 Summary
Chad asserts that stray cats spread disease and cause injuries to other cats and humans. He also claims that when people feed stray cats, this makes the problem of stray cats worse unless the stray cats are captured and adopted.
Objective
We’re looking for a point of agreement. The speakers agree that having lots of stray cats around is undesirable.
A
It is usually wrong to feed stray cats.
Sharita doesn’t express an opinion about this. Although she views the presence of stray cats as undesirable, that doesn’t imply any belief about feeding stray cats. Maybe she thinks it’s OK to feed them, but we should spay or neuter cats to get rid of future strays.
B
There are more stray cats than there should be.
This is a point of agreement. Sharita views having many stray cats as a reason to spay or neuter pet cats. Chad points out negate aspects of stray cats and considers feeding them as exacerbating the problem of stray cats.
C
Stray cats are a problem because of the risk they pose to humans.
Sharita doesn’t express an opinion about this. She doesn’t describe exactly why having lots of stray cats is undesirable.
D
Stray cats spread diseases to other cats.
Sharita doesn’t express an opinion about this. She doesn’t describe exactly why having lots of stray cats is undesirable.
E
It is mainly out of kindness that people feed stray cats.
Sharita doesn’t express an opinion about this. She doesn’t mention feeding or why people feed stray cats.