Examkin

Question

Difficulty: HardNecessary vs. Sufficient Condition Flaws

Review the following arguments regarding urban planning and infrastructure. Which of the arguments commit a logical flaw by either confusing a necessary condition with a sufficient condition, or mistaking a sufficient condition for a necessary one? Select all that apply.

  1. Implementing a congestion pricing zone is required to achieve a significant reduction in downtown air pollution. The city has just voted to implement a congestion pricing zone, so we can confidently expect a significant reduction in downtown air pollution.Answer
  2. Any urban area that strictly enforces noise ordinances will see an immediate improvement in residents' reported sleep quality. The northern district lacks the resources to strictly enforce its noise ordinances. As a result, the northern district will not see an immediate improvement in residents' sleep quality.Answer
  3. C
    A neighborhood must have adequate street lighting to be eligible for the community safety designation. Since the Riverside neighborhood clearly lacks adequate street lighting, it will not be eligible for the community safety designation.
  4. D
    Over the last decade, neighborhoods that expanded their public parks saw a simultaneous decrease in youth crime rates. It is clear that expanding public parks is an effective way to lower youth crime.
  5. E
    Unless a municipality invests heavily in modernizing its water drainage infrastructure, severe seasonal flooding is inevitable. The capital city refuses to invest in such modernization, which means severe seasonal flooding there is inevitable.

Answer

The arguments about the congestion pricing zone and the noise ordinances.
The correct selections are the two arguments that commit specific conditional reasoning flaws. The argument about the congestion pricing zone states that the zone is 'required' (a necessary condition) for reducing pollution, but then concludes that implementing it guarantees the reduction (treating it as sufficient). This is an illegal reversal. The argument about noise ordinances states that enforcing them guarantees better sleep (a sufficient condition), but then concludes that failing to enforce them guarantees sleep will not improve (treating it as necessary). This is an illegal negation.

Step-by-Step Solution

1
Analyze the prompt to identify the task.
The task requires identifying arguments that commit conditional reasoning flaws: illegal reversal (necessary confused for sufficient) and illegal negation (sufficient confused for necessary).
Clarifying the exact logical flaws targeted ensures we correctly distinguish between flawed conditionals, valid conditionals, and unrelated flaws.
2
Diagram and evaluate the conditional arguments to test for validity.
The congestion pricing argument diagrams as: Reduce Pollution -> Implement Zone. Premise: Implement Zone. Conclusion: Reduce Pollution. (Flawed). The noise ordinance argument diagrams as: Enforce Ordinances -> Improve Sleep. Premise: No Enforce Ordinances. Conclusion: No Improve Sleep. (Flawed).
Formal diagramming safely reveals whether an argument obeys the rules of sufficient and necessary conditions.
3
Evaluate the remaining arguments to classify their reasoning.
The street lighting argument uses valid contrapositive reasoning. The water drainage argument uses valid modus ponens. The public parks argument contains a causal flaw, not a conditional one.
Incorrect options must be eliminated either because they are logically valid or because they commit a different type of flaw entirely.

Key Concept

Necessary vs. Sufficient Condition Flaws
Rate this question

Topics

Necessary vs. Sufficient Condition Flaws

More questions from this topic