Necessary Assumptions
These questions ask what is an "assumption on which the argument depends." They are a very common logical reasoning question, with about 5 in every section. In all of these questions, there is an slight inconsistency between what is stated in the premise and what is stated in the conclusion. For example:
All young children like dinosaurs.
Therefore, Tom's youngest daughter Caylee likes dinosaurs.
The assumption is that Caylee is a "young child." "Youngest daughter" is a relative comparison and tells us nothing about her actual age. Caylee could be 80 years old for all we know.
On these questions, do not question the factual accuracy of the premise, i.e., whether it's actually true that all young children like dinosaurs. Rather, focus on the reasoning error.
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1. Brie cheese is considerably more expensive than cheddar cheese. Yet the fermentation process by which brie is produced does not vary considerably from the production of cheddar. The cost difference between the two types of cheese must thus have another explanation other than the cost of producing the cheeses.
The argument assumes which of the following?
(A) Grocers do not anticipate that consumers are willing to pay extra for brie cheese as opposed to cheddar cheese.
(B) There is little or no competition between companies that produce brie cheese.
(C) The milk used to produce brie cheese does not cost significantly more than the milk used to produce cheddar cheese.
(D) The production of cheddar is more expensive than the production of brie.
(E) Disparities in price between cheeses are the resultof only market factors and not production costs.
2. To ensure corporate responsibility, consumers must be able to criticize corporations for actions which are ethically questionable. But in the context of the environment, important corporate decisions are left to those with special knowledge on how to best protect the environment and comply with environmental laws. Because consumers tend to lack this basic knowledge, they have little impact on corporate responsibility in this area. Which one of the following is an assumption on which the argument depends?
(A) All of the decisions relating to the environment made by corporations are delegated to those with special knowledge.
(B) Corporate responsibility requires consideration of how to best protect the environment in light of special knowledge on how to do so.
(C) Ensuring corporate responsibility should be a main priority for consumers.
(D) Environmental concerns are often inconsistent with corporate interests.
(E) Basic knowledge of environmental protection is relevant to a consumer’s ability to criticize acorporation.
3. Some say that citizens should not worry too much about money. This, however, is a bad principle for a society which desires a strong economy. After all, the economy cannot reach its full potential if people are not fully pursuing the amount of wealth they could create.
Which one of the following is an assumption required by the argument?
(A) Those who are fully pursuing the wealth they could create are likely to acquire it.
(B) People who are not as troubled about money are less likely to strive for wealth.
(C) Wealth cannot be obtained by those who do not adequately concern themselves with money.
(D) People can legitimately cease to worry about money when they have achieved their full potential in creating wealth.
(E) Wealth does not contribute to a strong economy unless it is the maximum amount of wealth aperson could obtain.
4. Legal scholar: A constitution is not an unchanging principle, but a living breathing document. Because of this, there may be any number of different views on what the provisions of a constitution mean. Such interpretations usually are the result of political advocates attempting to invoke a constitutional protection, rather than looking for meaning within the document, and thus do not look to the intentions of those who created a constitution. Therefore, the interpretation of the provisions of a constitution invariably reflect the interpreter more than the author.
The argument depends on which one of the following assumptions?
(A) It is impossible to discern between the accuracy of various constitutional interpretations.
(B) An interpretation attempting to invoke a constitutional protection exemplifies things about the interpreter.
(C) An author’s intentions are of pertinence to a plausible interpretation of something written by the author.
(D) The most thorough understanding of a written work requires familiarity with the author.
(E) The exact intentions of the author of a constitutioncan never be known to one interpreting it.
5. Movements in developed countries to reduce global hunger are not likely to impact most of the world’s hungry people. It is true that people are receptive to human starvation. However, while people are likely to sympathize with fellow citizens in their own nations, they are unlikely to sympathize with people from different cultures in other nations. Thus, hungry people outside the developed world will receive little assistance.
Which one of the following is an assumption on which the argument depends?
(A) Global hunger alleviation is significant only if it is directed at all starving people worldwide.
(B) People in developed countries will not sympathize with starving people outside of the developed world.
(C) People will ignore problems unless the victims are those with which they can sympathize.
(D) Movements to reduce hunger are the most effective when they rely on appealing to sympathy.
(E) Most of the world’s hungry people do not live indeveloped countries.
6. The freighter Davies will not be on time if it is quarantined, and ships are quarantined if there is any outbreak of a serious illness at a port at which they have recently stopped. Furthermore, if the Davies is substantially late, it will be in breach of its voyage charter. Given the outbreak of malaria in Rio de Janiero and the standard four week quarantine at the ship’s next port of call, San Juan, the vessel will undoubtedly find itself liable to its voyage charterer.
The argument assumes each of the following EXCEPT
(A) A delay of four weeks can make a vessel substantially late.
(B) Malaria is a serious illness.
(C) The Davies will be quarantined in San Juan.
(D) A party that breaches its voyage charter will be liable to the voyage charterer.
(E) The Davies recently stopped at Rio de Janiero.
7. A dog cannot become an excellent hunting retriever without individualized, one-on-one training. Such training is done through simulated retrievals, gradually becoming more and more like the field. It is clear that attempting to train dogs in large groups is less likely to produce a highly skilled hunting retriever.
Which one of the following is an assumption on which the argument depends?
(A) Dogs trained in large groups are less likely to take part in simulated retrievals than those trained one-on-one.
(B) Training dogs in large groups frustrates a trainer’s ability to give individualized training to a dog.
(C) Graduated simulated retrievals increase, and do not negatively impact, a dog’s ability to become an excellent hunting retriever.
(D) Individualized, one-on-one training in large groups is unlikely to involve simulated retrievals.
(E) Individualized, one-on-one training is less likely tooccur when dogs are trained in large groups.
8. Medicine has often focused on finding cures for disease. However, while scientists continue to discover such cures, some diseases remain incurable. For instance, measles, caused by a single RNA strand virus of the Morbillivirus genus, cannot be stopped by anything but the human immune system. As curable diseases continue to be more readily treated, it follows that incurable diseases such as measles will make up a larger proportion of health detriments to the general public in the future.
Which one of the following is an assumption required by the argument?
(A) Incurable diseases such as measles will increasingly infect more and more people.
(B) The negative effects of a disease cannot be reduced if that disease is incurable.
(C) It is common for people to contract both curable and incurable diseases.
(D) Incurable diseases such as measles currently account for a relatively small fraction of the health detriments among the general population.
(E) More is being spent on finding cures for diseases as opposed to helping treat the ones known to becurable.
9. Governments which recognize and promote religious beliefs always attempt to commandeer such beliefs to their benefit. For example, under the “divine right of kings”, the absolute power of the monarchy was grounded in religion. It follows that many of the religious doctrines in nations with established religions are not rooted in theology, but designed to create a more submissive populace.
Which one of the following is an assumption on which the argument depends?
(A) The primary interest of every government is employing various societal functions to its benefit.
(B) Religious doctrines cannot be the result both of theology and a political agenda.
(C) A submissive populace can be perceived as beneficial to governments.
(D) Governments cannot commandeer religious beliefs without recognizing and promoting them.
(E) At least some religious doctrines would create amore submissive populace.
10. Criminologist: Many people argue for more rehabilitation of convicted criminals, claiming that rehabilitation reduces the chances of a future offense. However, in a recent study, convicted rapists who went through rehabilitation were just as likely to be repeat offenders as those who did not. The view that rehabilitation reduces future likelihood of criminal behavior is thus false, at least in the context of rapists.
The argument depends on assuming which one of the following?
(A) The recidivism of convicted rapists receiving rehabilitation is characteristic of criminals receiving rehabilitation as a whole.
(B) If rehabilitation advocates make one incorrect prediction, then all of their views are false.
(C) No study has ever found that rehabilitation of criminals reduces the likelihood of a future offense.
(D) The rehabilitation efforts directed at the rapists in the study was not limited to those thought to be highly likely to be repeat offenders.
(E) The crime rate as a whole did not change after bothgroups of rapists from the study were released.
11. Historian: This ancient book was obviously copied from multiple sources. This is clear because many accounts within it contradict each other. Furthermore, passages demonstrate widely different use of language, suggesting the writing of multiple authors.
The historian’s argument assumes that
(A) any book which exhibits widely different use of language was copied from multiple sources.
(B) no source from which the book may have been copied was itself copied from multiple sources.
(C) a book that has been copied from multiple sources cannot contain any original work.
(D) whether or not a book has been copied from multiple sources is relevant to its historicalaccuracy.
(E) a book cannot be accurate if it contradicts itself
12. Restaurant owner: While our pizza restaurant is considering purchasing a new model of oven, doing so would be a bad idea. Though the oven is more effective at baking pizza with a crispy crust, a taste test revealed that almost nobody noticed a taste difference between pizza from the type of oven the restaurant is considering buying and pizza from an oven like the one the restaurant uses now.
Which one of the following is an assumption on which the argument depends?
(A) If there is no substantial taste difference in pizza from the new oven, then there is no significant advantage to buying it.
(B) Better tasting pizza would justify the cost of the new oven.
(C) More people prefer crispy crust pizza as opposed to soft crust pizza.
(D) The restaurant cannot produce better tasting pizza through means other than purchasing a new oven.
(E) There are no other ovens the restaurant could purchase which would substantially enhance the quality of its pizza.
13. Globalization helps build connections between people and encourage commerce, peace and prosperity. However, such geographic integration happens at the local level first in the formation of large nations, leading to strong nationalism and ethnocentrism. Therefore, for a time, globalization increases the likelihood of conflict rather than decreases it.
The argument depends on which one of the following assumptions?
(A) Without connections between people, there cannot be peace.
(B) Any geographic integration will help to reduce the risk of conflict.
(C) Nationalism and ethnocentrism can influence the probability of the occurrence of conflicts.
(D) Globalization can never occur without some period of large nations, nationalism, and ethnocentrism.
(E) Any nation with strong nationalism andethnocentrism will be involved in a conflict.
14. Paying taxes to support government welfare programs tends to reduce citizens’ desire to provide assistance to others volitionally, since if people feel they are already contributing to the welfare of others through taxes which fund government welfare expenditures, they will feel that their obligation to society has been fulfilled. It follows that public welfare programs in fact have at least some detrimental impact on the public good.
Which one of the following is an assumption required by the argument?
(A) A reduction in the desire to assist others can have a negative effect on the public good.
(B) If people are forced to provide assistance to others, they are less likely to desire to provide assistance to others.
(C) Providing assistance to others is only beneficial if done volitionally.
(D) All citizens have some innate desire to assist others.
(E) Public welfare programs are not a manifestation ofcitizens’ desire to help others.
15. CEO: Most fast food restaurants serve very similar types of food–hamburgers, french fries, soda, and so forth. While some might argue that fast food restaurants are uninventive and are ignoring potential markets with their failure to introduce unique foods, this in fact is not the case. A fast food restaurant can only succeed if its menu is appealing to a large number of consumers.
Which one of the following is an assumption made by the CEO?
(A) Appealing to consumers is the most important consideration for a fast food restaurant.
(B) The menu of any given fast food restaurant contain no items unique to that chain of restaurants.
(C) The necessity of appealing to a large number of consumers is no different in the fast food context than it is in other contexts.
(D) Consumers may have unique tastes outside the mainstream, but these unique tastes are not shared by everyone.
(E) A fast food restaurant may lose its appeal to a large number of consumers through the introduction ofunique and different foods.
16. Single-sex education designed to benefit students through gender-tailored curricula usually is met with resistance in school districts. Indeed, some civil rights laws have been interpreted by courts to prohibit single-sex education, holding that it is a form of discrimination. Thus, some civil rights laws have had a negative impact on education.
The argument depends on which one of the following assumptions?
(A) Single-sex education would have been adopted in many school districts were it not prohibited by the rulings of courts interpreting civil rights laws.
(B) The main purpose of civil rights laws is to prohibit forms of discrimination.
(C) Civil rights laws in fact undercut many societal objectives.
(D) Inability to institute single-sex schools affects education to its detriment.
(E) Education cannot fully tailor its curricula without the use of single-sex schools.
17. Ringmaster: The two new acrobats at our circus have been instructed to perform routines too dangerous for rookie acrobats. In addition, they have been given too much responsibility in coordinating and directing such routines for acrobats who have never performed in a circus before. Their routines should be changed and their level of responsibility should be reduced.
The ringmaster’s argument assumes that
(A) the routines of the two new acrobats are just as dangerous as other acrobats in the circus.
(B) the level of responsibility delegated to the two new acrobats is no different than that typically given to those with similar levels of experience.
(C) the ringmaster was not given more dangerous than average routines as a new member of the circus.
(D) the two new acrobats are not experienced at what they do.
(E) the two new acrobats have been given their respective levels of responsibility because of the dangerous nature of the routines they are performing
18. Car owners and manufacturers often tout the high horsepower of their vehicles, horsepower being a measure of the output of the engine. However, this difference is irrelevant. Every car sold today is capable of driving the speed limit, and going over the speed limit is never worthwhile or useful given the relevant legal sanctions.
Which one of the following is an assumption required by the argument?
(A) The only factor in evaluating a car’s engine is whether or not it can drive the speed limit.
(B) Differences in the size, shape, and weight of a car do not have any impact on its top speed the way horsepower does.
(C) The term “horsepower” does not indicate an important concept for a car’s speed ability.
(D) There is no difference between engines based on horsepower other than their top speed.
(E) Cars with greater horsepower entice people to drive over the speed limit.
19. Sheriff: We have been trying to locate the two burglars for weeks but have had no luck. As it turns out, the eyewitness description of the burglars was inaccurate. The eyewitness described them as males in their teens or early twenties. After recovering video surveillance, however, it is clear that they are much older than this. Therefore, our current search, searching for two young males with stolen computer hardware, has been a complete waste.
Which one of the following is an assumption required by the sheriff’s argument?
(A) The current search did not locate any male suspects in their teens or early twenties.
(B) No other pieces of accurate information from the eyewitness description were or would have been useful in locating the burglars.
(C) The odds of catching the burglars have substantially increased since the video surveillance provided an accurate description.
(D) It is necessary to have an approximate age of a burglar to track down and apprehend the burglar.
(E) If police have an accurate description of a criminal, they can usually find that criminal.
20. Chronic alcohol consumption is detrimental to mental health. For instance, a recent study showed that those who frequently drink alcohol are several times more likely to suffer from depression than the general public. Such findings confirm that it would be in the public interest to encourage people to drink in moderation.
Which one of the following is an assumption required by the argument?
(A) Those who drink alcohol infrequently do not suffer from a greater risk of depression than those abstain from alcohol entirely.
(B) Among those who drink alcohol frequently, the more one drinks, the more likely it is that such a person suffers from depression.
(C) There is no practical way to improve mental health of chronic drinkers of alcohol other than by reducing their consumption of alcohol.
(D) Demographics with the lowest incidence of mental health also have the lowest levels of chronic alcohol consumption.
(E) Mental health does not influence the rate at which people drink alcohol.
21. Senator Houck continually touts his support for labor unions to the point where it is almost redundant. Yet Senator Houck is a hypocrite–he voted for the recent relaxation of this country’s steel tariff.
The argument depends on which one of the following assumptions?
(A) Senator Houck’s vote on the steel tariff is characteristic of his behavior on the matter.
(B) Voting for the relaxation of the steel tariff is indicative of not supporting labor unions.
(C) Steel workers are not treated in a substantially different matter from other union workers.
(D) People who are against the interests of labor unions will support the relaxation of tariffs.
(E) Voting against relaxation of the steel tariff is necessary for one to be supportive of labor unions.