Logical ReasoningDifficulty: Hard

PT5 S1 Q3 Explanation

Mayor of Plainsville: In order to help

A free, expert breakdown of this official LSAT Logical Reasoning question.

TopicsNecessary Assumption

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Stimulus

Mayor of Plainsville: In order to help the economy of Plainsville, I am using some of our tax revenues to help bring a major highway through new business to Plainsville.

Citizens’ group: You must have interests other than our economy in mind. If you were really interested in helping our economy, you would instead allocate the revenues to building a new business park, the business that your highway would.

What this question is testing

Necessary Assumption

Setup

The mayor wants to spend tax revenue on a highway to bring in business. The citizens' group says:

Evaluate

The whole accusation rests on the mayor knowing — or at least agreeing — that the business park would bring in more business. If the mayor genuinely thinks the highway is the better economic choice, then picking the highway is not evidence of ulterior motives; it is just evidence of disagreement about which option works better economically.

Imagine you tell a friend, That is only a fair accusation if your friend agrees salad is better for weight loss. If your friend genuinely thinks pizza is the diet move, you cannot accuse them of secretly not caring about weight loss — they just disagree with you.

Goal

Find the assumption that the mayor accepts the citizens' claim about which option works better.

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The question
3.

The argument by the citizens’ group relies on which one of the

Answer choices

  1. Bad Assumption1% picked this

    Plainsville presently has no major highways running

    Whether Plainsville already has a major highway is not necessary for the citizens' argument. The argument turns on which choice brings in more business and what the mayor's motives are. The town's current highway situation does not affect the inference about the mayor's motives.

  2. Correct50% picked this

    The mayor accepts that a new business park would bring in more new business than

    Why this is right

    This is the necessary link. The citizens' accusation is, "If you really cared about the economy, you would pick the better-for-the-economy option." That accusation only sticks if the mayor agrees the business park is the better-for-the-economy option. If the mayor disagrees — if he genuinely thinks the highway brings in more business — then choosing the highway is consistent with caring about the economy. Negate this answer and the citizens' argument falls apart.

    Skill tested: Necessary Assumption · how this choice captures the argument's function is the move to repeat next time.

  3. Too Strong21% picked this

    The new highway would have no benefits for Plainsville other than

    The citizens' argument compares the highway to the business park on the dimension of bringing in business. It does not require that the highway have no other benefits beyond business. The argument concerns a single comparison; other potential benefits of the highway are not denied or relied on.

  4. Out of Scope1% picked this

    The mayor is required to get approval for all tax revenue allocation plans from

    Whether the mayor needs city council approval is a procedural question that has nothing to do with the citizens' inference about his motives. The argument is about why the mayor proposes what he does, not about what process the proposal must go through.

  5. Too Strong27% picked this

    Plainsville's economy will not be helped unless a new business park of the sort envisioned by the

    This says the business park is the only way to help the economy. The citizens' argument does not require that — it only requires that the business park is better than the highway on the economic dimension. The economy could be helpable in other ways too; the argument does not depend on excluding them.

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