Flaw Questions

Flaw questions are one of the most common types of logical reasoning question; there are often around 5 per section.  The trick with these is to try and identify the flaw in advance.

Our private LSAT lessons are $50 per hour...message us today for LSAT help!

1.  Environmentalist: The New England Cottontail is a rare rabbit species on the verge of being endangered, but the governor still refuses to support restrictions on rabbit hunting. The governor is clearly letting our local wildlife become extinct for political gain. While the governor is correct that rabbit hunters in this state disproportionately hunt the Eastern Cottontail which is displacing the New England Cottontail, it is equally true that the governor was supported by the hunting lobby.  There is even a campaign picture of the governor smiling with a pair of rabbits in hand.

The environmentalist’s reasoning is flawed because

(A) it fails to consider that the governor’s support from the hunting lobby does not suggest in any way an ulterior motive on the part of the governor

(B) it overlooks the possibility that the actions of the governor, while consistent with lobbyist interest, are nonetheless compatible with protecting the New England Cottontail

(C) it fails to establish that the environmentalist does not have just as strong of an ulterior motive for supporting restrictions on rabbit hunting

(D) the fact that an activity is correlated with an undesirable results does not mean that the activity causes this result

(E) it neglects to consider the governor may nonetheless have a stronger interest in protecting the Eastern Cottontail than in appeasing constituents from the hunting lobby  

2.  The works of Jane Austen are clearly anti-egalitarian, given their revolution around the English gentry. While Austen clearly wrote works to the liking of audiences, she nonetheless chose a focus on the upper-class of society, and this carries with it the suggestion that the upper-class is more important than other components of society, which is in turn a notion contrary to egalitarianism.

Which one of the following is a flaw in the argument?

(A) It presumes, without providing justification, that anything which suggests an idea anti-egalitarian is, in fact, anti-egalitarian.

(B) It overlooks the possibility that writing to the liking of audiences can also contain a pro-egalitarian message.

(C) It takes for granted that appealing to the taste of audiences was the only reason for Austen to focus on the upper-class of society.

(D) It fails to consider the possibility that Austen’s works were less anti-egalitarian than that of other contemporaries.

(E) It draws an unwarranted conclusion about an author solely based on only some of the works of thatauthor.  

3.  Ms. Makela, who lives next door, says that butter from Iceland is better than most butter because the grass in Iceland receives longer days of more direct sunlight in the summertime, giving dairy animals more nutrients when they eat it and improving their milk production. However, Ms. Makela also believes in outrageous things like ghosts and space aliens. Thus, butter from Iceland is probably not much different from butter from other places.

The argument’s reasoning is questionable because

(A) it cites evidence which is only a restatement of its conclusion

(B) it attacks the person making the assertion and does not discuss the merits of the claim

(C) it draws an improper analogy between two things which differ in important respects

(D) it asserts that a claim is true solely on the basis of lack of evidence to the contrary

(E) it dismisses a course of action on the basis of infeasibility instead of drawing a warranted conclusion 

4.  Christina is very allergic to dogs and sneezes wildly in the presence of someone who has been with one for a long time. She asked that Alison, who had been hiking with her cocker spaniel all day, to take a shower before coming to the rehearsal dinner, and Alison said she would. However, while at the rehearsal dinner, Christina was sneezing uncontrollably. Alison must not have taken a shower before she came to the rehearsal dinner.

The argument is flawed because it

(A) fails to consider different situations can lead to actions not previously planned

(B) neglects to take into account someone might not do a particular action even after committing to do so

(C) utilizes terminology objectively despite the term being inherently subjective

(D) presumes, without providing justification, that something caused by one circumstance is only caused by that circumstance

(E) fails to consider that failing to take an action that would have prevented a particular result does notguarantee that this result will happen  

5.  The works of Shakespeare were written for theaters in which people shuffled in and out a great deal and talked to each other. For this reason, Shakespeare’s plays contained a great deal of repetition so that audience members would always know what was happening in the plot of the play.  We can conclude that the works of Shakespeare would contain much less repetition had the audiences in theaters of his era typically been attentive to the entire play.

The argument is flawed because it

(A) concludes that because a result is due to one particular factor, it is due only to that factor

(B) infers that because one result is due to one particular factor, other results must be due to that same factor

(C) fails to consider that many other factors impacted the works of Shakespeare in some way

(D) overlooks the possibility that repetition might not have been necessary even given the circumstances in Shakespeare’s time

(E) presumes that it would’ve been possible for audiences to be more attentive in the time ofShakespeare  

6.  Michelle: The Venetian Republic was a tiny nation that consisted of little more than a few inhabited lagoons for most of its existence. Yet the influence of this nation in the history of the world is striking – the Venetians had a profound impact in politics and warfare, as well as in art and music. This shows that a nation need not be largeto be important and influential.

Daniel: While it may have been possible for small nations to have a striking impact in the Middle Ages, this is not true today. To be influential in the world today, a nation must command a large economy.

Daniel’s reasoning in his response to Michelle is most vulnerable to criticism on the grounds that it

(A) neglects to consider the possibility that a small nation can still command a large economy

(B) fails to address whether the Venetian Republic was a large nation or economy for its time

(C) uses the word “influential” in a different sense than Michelle used it

(D) presumes, without providing justification, that the Venetian Republic was more influential than other contemporaneous small nations

(E) does not cast in to doubt the assertions made byMichelle about the Venetian Republic  

7.  Clothing Retailer: Our store is making considerably more money off frocks than we used to.  Last year frocks represented 6% of our profits, and the year before, they were only 4% of our profits. However, this year, 11% of our profits were made off frocks.

The clothing retailer’s argument is questionable because it

(A) fails to consider that if the store is making more money off frocks, it is making less money off other merchandise

(B) fails to consider the possibility that the store could make more money selling another type of merchandise instead of frocks

(C) presumes, without providing justification, that what is true of sales this year is true of sales every year

(D) improperly concludes that there is a causal relationship between two things merely on the basis of a correlation between those things

(E) confuses a percentage of the store’s profit with an absolute amount 

8.  Attorney: It is clear that Mr. Lederman was driving much faster than the speed limit when the car accident occurred. While no one saw the accident, Mr. Lederman’s neighbor, Mrs. Griffin, saw Mr. Lederman drive off at a dangerously high speed minutes before the accident occurred. Mr. Lederman has presented nothing to cast doubt on this testimony.

The attorney’s argument is flawed because it reasons that

(A) driving over the speed limit moments before an accident does not indicate that a person was driving fast at the moment of the accident

(B) Mrs. Griffin’s account of Mr. Lederman’s behavior is accurate because Mrs. Griffin was not driving over the speed limit or involved in an accident

(C) because Mr. Lederman did not rebut account given by his neighbor, he must have been speeding at the time of the accident

(D) Mr. Lederman’s account would be unreliable because he was the one involved in the accident

(E) a person who was drives off at a dangerously high speed will always continue to drive that speed for atleast some time after  

9.  Physicist: Though many theorize that “antimatter” indeed exists and makes up a large portion of the universe, no scientist has ever conclusively established via experiment that there is such a substance, much less how prevalent it is. Until this is done, we must conclude that there is no such thing as antimatter.

The physicist’s argument is flawed because it

(A) ignores the possibility that some experimental attempts to prove the existence of antimatter reached incorrect conclusions

(B) presumes, without providing justification, that experiments are the only factor to be considered in evaluating whether antimatter exists

(C) takes for granted that there is a way to demonstrate the existence of antimatter through an experiment

(D) neglects to consider that a claim may be true even if no existent evidence has established it to be true

(E) overlooks the possibility that something can existeven if is not common  

10.  Oenologists judge wine by tasting it, and claim to distinguish between regional wine grown in different seasons as better or worse. For instance, 2004 may be decidedly a better year for Pinot Grigio because of the superior flavor of the wine. However, the opinions of different people in tasting wine vary greatly and there is no single ordinary opinion of the taste of a given wine. It follows that the idea that certain seasons of wines are better than others is a flawed concept.

The argument above is vulnerable to criticism because it

(A) fails to consider that non-oenologists can make their own judgments about the flavor of wine grown in a given year

(B) draws a conclusion about wine in general based on a premise that involves only one specific type of wine

(C) ignores the possibility that oenologists may overwhelmingly come to the same conclusion about the flavor of wine in a given year even if the opinions of all people are subject to a great deal of variation

(D) presumes, without providing justification, that the quality Pinot Grigio varies more greatly by season than other varieties of wine

(E) presumes, without providing justification, that the season a wine is grown in is completely irrelevantto its flavor and taste  

11.  Tom: If there is a bridge over the Heron River wide enough to accommodate these modular units, we can haul the units to Potterville by the time this day is over. However, while there are bridges wide enough after the Heron River flows into the Crane River, there is no wide enough bridge along the Heron River itself. Therefore, we cannot get the units to Potterville by the end of today.

Which one of the following best describes a flaw in Tom's argument?

(A) It overlooks the possibility that some of the modular units do not need to go to Potterville by the end of today.

(B) It fails to take into account that there may be rivers other than the Heron River which have bridges wide enough to accommodate the modular units.

(C) It takes for granted that it would have been possible to build a wider bridge on the Heron River.

(D) It presumes, without providing justification, that the lack of a wide enough bridge on the Heron River precludes a result that could’ve been achieved if such bridge existed.

(E) It fails to consider the possibility that there may be other problems with a bridge even if that bridge iswide enough to accommodate the modular units.  

12.  Penny: Uncle Hal left everything on his farm to us and your sister Mary, including his two Shire horses. We do not have enough room to take care of the two horses at our little house in the city, and Aunt Mary, while she has enough room at her house in the country, is too sick to be able to do all the work to care for the horses. Therefore, none of the heirs of Uncle Hal will not be able to care for his horses, and sadly we will have to get rid of them.

Which one of the following best describes a flaw in

Penny’s argument?

(A) It fails to consider that what is true of members of a group are true of the group as a whole.

(B) It treats a correlation as conclusive evidence of a causal relation.

(C) It infers that something is false based on an absence of evidence that it is true.

(D) It fails to consider that someone other than the heirs of Uncle Hal could take over caring for his horses.

(E) It overlooks the possibility that Uncle Hal has otherthings which his heirs will not be able to care for.

13.  This region is bound to decline economically.  Long ago, the area was important because it was rich in anthracite coal, which helped fuel the industries of the era. However, anthracite coal has now fallen out of favor and, there are no longer any anthracite mining operations which once led to the population and development of this reason. The area's decline is thus unavoidable.

The argument is flawed because it

(A) draws unwarranted conclusions based on appeals to authority

(B) assumes that because a result is possible, it is inevitable

(C) presupposes the point it seeks to prove

(D) fails to define what it means by “decline”

(E) confuses the source of a given result with asomething necessary for that given result 

14.  Researchers, attempting to comprehend and ultimately remedy damage to ocean ecosystems routinely use expendable bathythermographs, which are devices discarded in the water after a reading is taken. Many pollution activists have criticized the use of these devices since their use leaves refuse in the water just as littering does, and since littering is wrong, so should be the use of these devices.


Which one of the following best describes a flaw in the pollution activists’ reasoning?

(A) It presumes, without providing proper justification, that the use of expendable bathythermographs always does harm to an ocean ecosystem.

(B) It analogizes two different quantities which are not in any way connected.

(C) It does not draw a distinction between remedying damage to ocean ecosystems and preventing such damage.

(D) It draws a generalization based on a specific example.

(E)It treats two things which differ substantially as though they do not differ substantially.