Logical Reasoning

PT121 · S4 · Q10 The proposed coal-burning electric

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The proposed coal-burning electric plant should be approved, since no good arguments have been offered against it.

Conclusion

The proposed coal-burning plant should be approved.

Intermediate Conclusion

No good arguments have been offered against it.

Premise

All the arguments against it were presented by competing electricity producers

Evaluate

This is weirdly an Ad Hominem flaw showing up in Necessary Assumption instead of Flaw. The words "since" and "after all" showed us premises, which indirectly showed us conclusions. This argument has a three part structure, so we're allowed to be tested on the move from Premise to Intermediate Conclusion, or from IC to Main Conclusion.

argument made ~Good argument should be by competing → against → approved electricity producer

Goal

This has some pretty glaring language shifts, so we can look for an answer that spells out or one that spells out .

However, we should stay flexible for any answer that, if negated, would allow us to argue that there still might be a good argument against it, or that would allow us to argue that the proposed plant shouldn't be approved.

10.

Which one of the following is an assumption on which the reasoning above depends?

  1. The competing electricity producers would

    Out of Scope

    Out of Scope: lose large amounts of $ Our author is certainly suspicious of the validity of arguments coming from competitors, but we don't specifically know why she's suspicious. We can't say she's definitely assuming they would stand to lose large amounts of revenue.

    6% picked this

  2. If a person’s arguments against

    Backwards Logic

    We are interested in any answer that says competitor said not good it (vested interest) ? argument But this answer gives us that backwards: Not good argument ? Vested Interest

    5% picked this

  3. Approval of the coal-burning electric

    Out of Scope: who's pleased more

    This is talking about the ramifications of approving the plant. That's beyond the scope of the argument. This author is just trying to get us to "we should approve". She hasn't staked any opinion on what happens after that.

    2% picked this

  4. If good arguments are presented

    Bad Premise Match

    Our author assumes this: no good arguments against ? should be approved This answer says this: good arguments in favor ? should be approved We were never told whether there are / aren't good arguments in favor of the proposal, so that's out of scope.

    6% picked this

  5. Correct

    Arguments made by those who

    Why this is right

    This tests the link from Premise to Intermediate Conclusion. arguments made by those with vested ? not good arguments interest in outcome Our author definitely made this move in saying, "No good arguments have been made against; after all, all arguments against have come from a competitor." That clearly reflects an assumption that "if an argument comes from a competitor, it's bad". If we negated this answer, it would turn into an Objection (as correct answers are supposed to): Sometimes arguments made by those with a vested interest are good arguments!

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

    81% picked this

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