Salesperson: When a salesperson is successful, it is certain that that person has been in sales for at least three years. This is because to succeed as a salesperson, one must first establish a strong client base, and studies have shown that anyone who spends at least three years developing a client base can eventually make a comfortable living in sales.

A
salespeople who have spent three years developing a client base might not yet be successful in sales

The author doesn't fail to consider this possibility. According to his conclusion, spending 3+ years in sales is necessary for being successful, not sufficient. This allows for the possibility of some salespeople spending 3+ years in sales and not yet being successful.

B
some salespeople require fewer than three years in which to develop a strong client base

The author fails to consider this possibility. He never proves that to establish a strong client base, one must spend 3+ years in sales. Some people might establish their client base in less time and so be successful without spending 3+ years in sales.

C
a salesperson who has not spent three years developing a client base may not succeed in sales

The author concludes that someone who hasn’t spent three years in sales will not succeed in sales. Unlike (C), he fails to consider the possibility that a salesperson who hasn’t spent three years developing a client base may succeed in sales.

D
it takes longer than three years for a salesperson to develop a strong client base

The author doesn’t fail to consider this possibility. He mistakenly assumes that a salesperson must spend at least three years developing a strong client base. This allows for the possibility of some people spending longer than three years establishing it.

E
few salespeople can afford to spend three years building a client base

The author may not address this, but it isn’t a flaw in his argument. Just because most salespeople can’t afford to spend three years building their client base doesn’t affect the conclusion that spending three years in sales is necessary for success.


27 comments

Doctor: Being overweight has long been linked with a variety of health problems, such as high blood pressure and heart disease. But recent research conclusively shows that people who are slightly overweight are healthier than those who are considerably underweight. Therefore, to be healthy, it suffices to be slightly overweight.

Summarize Argument

The doctor concludes that being slightly overweight is sufficient for being healthy. She supports this by citing recent research that shows that slightly overweight people are healthier than those who are very underweight.

Identify and Describe Flaw

This is the flaw of confusing a relative and an absolute property; the author assumes that a relative relationship proves an absolute property.

In this case, the doctor assumes that being slightly overweight makes one healthy just because it's relatively healthier than being very underweight. But a person could still be slightly overweight and unhealthy, even if they're healthier than someone who's very underweight.

A
ignores medical opinions that tend to lead to a conclusion contrary to the one drawn

The doctor acknowledges the fact that being overweight has long been linked with a variety of health problems. She just goes on to conclude that being slightly overweight is sufficient for being healthy.

B
never adequately defines what is meant by “healthy”

The doctor never defines the term “healthy,” but she doesn’t need to. So (B) doesn’t describe why her reasoning is flawed.

C
does not take into account the fact that appropriate weight varies greatly from person to person

The doctor is talking about being overweight and underweight; she doesn’t address appropriate weight at all. Either way, this doesn’t affect her argument; she’s likely aware that appropriate weight varies from person to person.

D
holds that if a person lacks a property that would suffice to make the person unhealthy, then that person must be healthy

The doctor never makes a claim about “a property that would suffice to make a person unhealthy,” much less claim that lacking such a property would make one healthy. Instead, she makes a claim about a property that would suffice to make one healthy— being slightly overweight.

E
mistakes a merely relative property for one that is absolute

The author mistakes a merely relative property— being healthier than someone else— for one that is absolute— being healthy. But a person could still be slightly overweight and unhealthy, even if they're healthier than someone who's very underweight.


16 comments

People perceive color by means of certain photopigments in the retina that are sensitive to certain wavelengths of light. People who are color-blind are unable to distinguish between red and green, for example, due to an absence of certain photopigments. What is difficult to explain, however, is that in a study of people who easily distinguish red from green, 10 to 20 percent failed to report distinctions between many shades of red that the majority of the subjects were able to distinguish.

"Surprising" Phenomenon
Why did 10 to 20 percent of people who could easily distinguish red from green fail to report a distinction between many shades of red that the majority of people who could distinguish red from green were able to distinguish?

Objective
The correct answer will be the only answer that doesn’t help explain the phenomenon where 10 to 20 percent of people who could easily distinguish red from green failed to report a distinction between many shades of red. The correct answer must give us information that doesn’t affect our understanding of the phenomenon or information that makes the phenomenon more difficult to explain.

A
People with abnormally low concentrations of the photopigments for perceiving red can perceive fewer shades of red than people with normal concentrations.
This could account for the non-colorblind people who were unable to distinguish between certain shades of red. They may have had an abnormally low concentration of the photopigments for perceiving red.
B
Questions that ask subjects to distinguish between different shades of the same color are difficult to phrase with complete clarity.
If these sorts of questions are difficult to phrase clearly, the non-colorblind people who failed to distinguish between certain shades of red may have actually been able to distinguish between the shades but just misunderstood the questions they were being asked.
C
Some people are uninterested in fine gradations of color and fail to notice or report differences they do not care about.
If (C) is true, the people who failed to distinguish between the various shades of red may have actually been able to distinguish between the shades but just didn’t care enough about the distinctions to notice them or report them.
D
Some people are unable to distinguish red from green due to an absence in the retina of the photopigment sensitive to green.
Reasons why some people can’t distinguish red from green are irrelevant. We need to know why 10 to 20 percent of the people who are capable of distinguishing red from green failed to distinguish between many shades of red.
E
Some people fail to report distinctions between certain shades of red because they lack the names for those shades.
If (E) is true, the people who failed to distinguish between the various shades of red may have actually been able to distinguish between the shades but just didn’t know the words necessary to report the distinctions.

7 comments

Occultist: The issue of whether astrology is a science is easily settled: it is both an art and a science. The scientific components are the complicated mathematics and the astronomical knowledge needed to create an astrological chart. The art is in the synthesis of a multitude of factors and symbols into a coherent statement of their relevance to an individual.

Summarize Argument

The occultist concludes that astrology is both an art and a science. She says that the scientific components come from the math and astronomy used to create an astrological chart, while the art is in combining various factors and symbols to make meaningful statements about a person.

Identify and Describe Flaw

This is the cookie-cutter flaw of confusing part v. whole, where the author assumes that what’s true about the individual parts of something must also be true about that thing as a whole.

In this case, the occultist assumes that astrology is a science simply because some parts of astrology involve components of science.

A
presumes, without providing justification, that any science must involve complicated mathematics

Like (E), the occultist never makes any claims about any science. She just claims that astrology is a science because it involves complicated mathematical and astronomical knowledge.

B
incorrectly infers that a practice is a science merely from the fact that the practice has some scientific components

The occultist incorrectly infers that the whole practice of astrology is a science merely from the fact that astrology has some scientific components— mathematical and astronomical knowledge.

C
denies the possibility that astrology involves components that are neither artistic nor scientific

The occultist doesn’t deny this possibility. Astrology might involve other components, like religious or spiritual components, that aren’t artistic or scientific. But this doesn’t affect the argument that it’s an art and a science.

D
incorrectly infers that astronomical knowledge is scientific merely from the fact that such knowledge is needed to create an astrological chart

The occultist incorrectly infers that astrological— not astronomical— knowledge is scientific from the fact that astronomical knowledge is needed to create an astrological chart.

E
presumes, without providing justification, that any art must involve the synthesis of a multitude of factors and symbols

Like (A), the occultist never makes any claims about any art. She just claims that astrology is an art because it involves the synthesis of a multitude of factors and symbols.


22 comments