LSAT (Law School Admission Test)Logical ReasoningMedium
A city planner argues: 'To alleviate traffic congestion, we must either expand our existing road network or significantly invest in public transport. Since expanding roads is too costly and environmentally damaging, we must significantly invest in public transport.'\n\nThe city planner's argument is flawed because it:
- APresents only two options as if they are the only possible solutions to the problem.
- BAssumes that traffic congestion is solely caused by insufficient infrastructure.
- CRelies on an appeal to fear regarding environmental damage.
- DFails to consider that public transport investment might also be costly.
Show answer & explanationAnswer & explanation
Correct answer: A. Presents only two options as if they are the only possible solutions to the problem.
The city planner presents only two options (expand roads OR invest in public transport) as if they are exhaustive, then eliminates one to conclude the other must be true. This is the False Dichotomy fallacy, also known as a false dilemma, where other potential solutions are ignored.
Why the other options are wrong
- B. This is an assumption the argument makes, but the primary flaw is the limited set of solutions considered, not the cause of congestion.
- C. While environmental damage is mentioned, it's presented as a factual drawback, not an emotional appeal.
- D. While true, this doesn't identify the fundamental flaw in the structure of the argument, which is the limited choice presented.
False Dichotomy (False Dilemma)
A fallacy that presents only two options or sides when, in reality, there are more. It forces a choice between two extremes.
- Also known as 'either/or fallacy'.
- Ignores a spectrum of possibilities or other viable alternatives.
- Often used to simplify complex issues or manipulate an audience.
Memory trick: Life isn't black or white; look for the grey.