LSAT Principle and Parallel Reasoning 2 — Questions and Answers
Question 1: A city council member argues: 'We should fund programs that benefit the greatest number of residents. The new library branch benefits only 200 residents, while road repairs benefit 50,000 residents. Therefore, we should fund road repairs instead of the library.' Which principle, if valid, most directly supports this argument?
- Public funds should be allocated to maximize the number of beneficiaries. (Correct answer)
- Libraries are less important than transportation infrastructure.
- Road repairs are always a higher priority than cultural institutions.
- Government programs should be evaluated based on their cost per resident.
Correct answer: Public funds should be allocated to maximize the number of beneficiaries.
The argument relies on the principle that public funding decisions should maximize the number of people who benefit, which directly justifies choosing road repairs over the library.
Question 2: Which of the following arguments most closely parallels this reasoning: 'Since all published research requires peer review, and this manuscript has not been peer reviewed, it should not be cited as established science'?
- Since all licensed drivers must pass a test, and this person passed a test, they must be a licensed driver.
- Since all legitimate currencies are government-issued, and this token is not government-issued, it is not legitimate currency. (Correct answer)
- Since some peer-reviewed articles contain errors, peer review is not a guarantee of accuracy.
- Since all science requires evidence, and this claim lacks evidence, scientists should ignore it.
Correct answer: Since all legitimate currencies are government-issued, and this token is not government-issued, it is not legitimate currency.
The original argument has the form: All X require Y; this lacks Y; therefore it is not X — option B mirrors this structure exactly with currencies and government issuance.
Question 3: A teacher states: 'Students who cheat undermine academic integrity. Anyone who undermines academic integrity should face consequences. Therefore, students who cheat should face consequences.' Which argument below uses the same logical structure?
- Factories that pollute harm the environment, and anything that harms the environment should be regulated, so polluting factories should be regulated. (Correct answer)
- Students who study hard get good grades, so students who want good grades should study hard.
- Anyone who lies is untrustworthy, and untrustworthy people should not be hired, but some liars can be reformed.
- Rules exist to protect people, and cheating violates rules, so cheating ultimately harms people.
Correct answer: Factories that pollute harm the environment, and anything that harms the environment should be regulated, so polluting factories should be regulated.
Both arguments use a syllogistic chain: A does B; anything that does B deserves C; therefore A deserves C — the pollution argument mirrors this precisely.
Question 4: A principle states: 'An action is morally permissible only if it respects the autonomy of all affected parties.' A judge applies this principle to rule that a company's nondisclosure agreement is impermissible. Which scenario best justifies this ruling?
- The NDA prevents employees from discussing their own health conditions with doctors. (Correct answer)
- The NDA stops competitors from using trade secrets.
- The NDA limits the company's own advertising choices.
- The NDA requires employees to attend training sessions.
Correct answer: The NDA prevents employees from discussing their own health conditions with doctors.
Preventing employees from discussing their own medical conditions with doctors undermines their personal autonomy, directly violating the stated principle.
Question 5: Analyst: 'Countries that maintain trade deficits consistently experience currency depreciation. Ruritania has maintained a trade deficit for five years. Therefore, Ruritania's currency has depreciated.' The flaw in this reasoning most closely parallels which of the following?
- All mammals breathe air. Dolphins breathe air. Therefore, dolphins are mammals.
- Heavy smokers often develop lung disease. This patient has lung disease. Therefore, this patient is a heavy smoker. (Correct answer)
- All cars need fuel. This vehicle needs fuel. Therefore, this vehicle is a car.
- Students who skip class fail exams. Jana skipped class. Therefore, Jana will fail her exam.
Correct answer: Heavy smokers often develop lung disease. This patient has lung disease. Therefore, this patient is a heavy smoker.
The analyst's error is affirming the consequent — concluding that because a common effect is present, the usual cause must be present — and option B makes the identical error.
Question 6: A principle holds that a witness's testimony should be discounted whenever they have a financial interest in the outcome. A lawyer argues this principle supports dismissing a forensic accountant's testimony. Which additional fact would most strengthen this application of the principle?
- The accountant was paid a flat fee regardless of the case outcome.
- The accountant's firm stands to gain a major contract if the defendant is convicted. (Correct answer)
- The accountant has testified accurately in 50 previous cases.
- The accountant holds a certification from a nationally recognized body.
Correct answer: The accountant's firm stands to gain a major contract if the defendant is convicted.
If the accountant's firm benefits financially from a conviction, the accountant has a financial interest in the outcome, directly triggering the principle's discount rule.
Question 7: The following argument: 'Every senator who voted for the bill received campaign donations from the energy industry. Senator Marsh voted for the bill. So Senator Marsh received donations from the energy industry.' This argument is MOST similar in structure to which of the following?
- Every athlete on the team trains daily. Rivera trains daily. So Rivera is on the team.
- Every winner of the prize studied abroad. Chen won the prize. So Chen studied abroad. (Correct answer)
- Most scientists who study climate have published in Nature. Dr. Kim studies climate. So Dr. Kim has probably published in Nature.
- All scholarship recipients maintain a 3.8 GPA. Tyler has a 3.8 GPA. So Tyler must be a scholarship recipient.
Correct answer: Every winner of the prize studied abroad. Chen won the prize. So Chen studied abroad.
The original has the valid form: All A are B; X is A; therefore X is B — option B mirrors this exactly with prize winners and studying abroad.
LSAT Principle and Parallel Reasoning 2
A city council member argues: 'We should fund programs that benefit the greatest number of residents.
The new library branch benefits only 200 residents, while road repairs benefit 50,000 residents.
Therefore, we should fund road repairs instead of the library.' Which principle, if valid, most directly supports this argument?