LSAT Logical Reasoning : Parallel Reasoning
Study concepts, example questions & explanations for LSAT Logical Reasoning
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Example Questions
Example Question #11 : Determining Which Answer Uses Parallel Reasoning To The Argument Provided
The local ice cream shop decided to stop offering cappucino-flavored ice cream to its customers. Anna was disappointed by this decision, because cappucino was her favorite ice cream flavor. Therefore, the local ice cream shop intentionally disappointed Anna.
The flawed reasoning above most closely resembles the reasoning in which of the following arguments:
Brittany stole 12.00 from Lindsey and bet it in Vegas. Then Brittany won 200.00 in Vegas. Therefore, Brittany actually stole 200.00 from Lindsey.
Laura knows that Dungeness Crab is caught in Humboldt Bay, and that Humboldt Bay is in Northern California. Therefore Laura should know that dungeness crab is caught in Northern California.
The lightning caused the power to go out, and the power outage caused the meat in the refrigerator to spoil. Therefore, the lightning caused the meat in the refrigerator to spoil.
The treatment plant increased the chlorine in the water, and whatever increased the chlorine in the water is responsible for the decrease in the frog population. Therefore, the treatment plant is responsible for the decrease in the frog population.
Becca intentionally planted her flowers in the sun. Unfortunately, these particular flowers prefer shade, so the intense sunlight killed the flowers. Therefore, Becca intentionally killed her flowers.
Becca intentionally planted her flowers in the sun. Unfortunately, these particular flowers prefer shade, so the intense sunlight killed the flowers. Therefore, Becca intentionally killed her flowers.
The flawed argument states that performing an intentional act led to a certain consequence, and draws the incorrect conclusion that the consequence itself was therefore intended. Similarly, the correct answer choice confuses an intentional act that resulted in a negative consequence with the intent to bring about that consequence.
Example Question #12 : Determining Which Answer Uses Parallel Reasoning To The Argument Provided
Every successful business has a smart CEO or good customer service. The CEO at John's company is not smart, so the company's customer service must be good.
Which of the following most closely resembles the flawed logic exemplified above?
Every famous athlete has immense talent or a good sports agent. Henry's brother plays baseball and has immense talent, so he must have a good sports agent.
Every famous athlete has immense talent or a good sports agent. Henry's brother plays baseball and has a good sports agent, so he must have immense talent.
Every famous athlete has immense talent or a good sports agent. Henry's brother plays baseball. He is not talented, so he must not have a good sports agent.
Every famous athlete has immense talent or a good sports agent. Henry's brother plays baseball and has immense talent, so he must be a famous athlete.
Every famous athlete has immense talent or a good sports agent. Henry's brother plays baseball but is not talented, so he must have a good sports agent.
Every famous athlete has immense talent or a good sports agent. Henry's brother plays baseball but is not talented, so he must have a good sports agent.
The passage states, "Every successful business has a smart CEO or good customer service." It says nothing, however, about whether John's company is successful. Therefore, we can't reasonably deduce that it has good customer service just because the CEO isn't smart.
Similarly, we know that Henry's brother plays baseball, but not that he is a famous athlete. Therefore, just because he does not have talent does not mean that he has a good sports agent.
Example Question #13 : Determining Which Answer Uses Parallel Reasoning To The Argument Provided
Every successful marriage is built upon trust and compassion. Daniel and Beth do not have a successful marriage. Clearly, they do not trust each other.
Which of the following most closely resembles the flawed reasoning outlined above?
All skyscrapers have a solid foundation and are designed with classical architectural styles. This building is not a skyscraper. It was not designed with a classical architectural style.
All skyscrapers have a solid foundation and are designed with classical architectural styles. This building was constructed with a modernist design. It must not be a skyscraper.
All skyscrapers have a solid foundation and are designed with classical architectural styles. This building has a classical architectural style. It must have a solid foundation.
All skyscrapers have a solid foundation and are designed with classical architectural styles. This building is not a skyscraper. It must not have a solid foundation.
All skyscrapers have a solid foundation and are designed with classical architectural styles.
All skyscrapers have a solid foundation and are designed with classical architectural styles. This building is not a skyscraper. It must not have a solid foundation.
The reasoning in the passage is flawed because it presumes to know which (if either) of the necessary conditions is not satisfied in order for the marriage to be unsuccessful.
Similarly, just because the building does not qualify as a skyscraper does not mean that we know that its foundation is unstable.
Example Question #14 : Determining Which Answer Uses Parallel Reasoning To The Argument Provided
All limes are green. Therefore, any fruit that is green is a lime. If a person sees a fruit that is green, that person may assume that the fruit is a lime.
Which of the following most closely parallels the flawed reasoning above?
Immigration courts adopt more liberal views. Therefore, any court that adopts a more liberal view is an immigration court. If a person encounters a court that has a more liberal view, that person may assume that the court is an immigration court.
Liberal views are expressed in immigration courts. Therefore, immigration courts are liberal. If a person encounters a liberal view, that person can assume that the view was expressed in an immigration court.
Liberal views are often expressed in immigration courts. Therefore, if a person encounters a liberal view, it is likely that the view was expressed in an immigration court.
Immigration courts have more liberal views. Therefore, liberal views are only expressed by immigration courts. Therefore, if a person encounters an immigration court, that person can assume that the court will have a liberal view.
Immigration courts tend to adopt more liberal views. Therefore, if a person encounters a conservative view, it is unlikely that the view was expressed in an immigration court.
Immigration courts adopt more liberal views. Therefore, any court that adopts a more liberal view is an immigration court. If a person encounters a court that has a more liberal view, that person may assume that the court is an immigration court.
The flawed reasoning in the text is as follows:
X has trait Y. Therefore, anything with trait Y must be X. If a person encounters something with trait Y, then it must be X.
The correct answer properly reflects this reasoning. All the other answer choices do not properly follow this pattern: they may leave out a link of the causal reasoning or misconstruct it.
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