PrepTest 114, Section 2, Question 23

Parallel FlawDifficulty3 of 5
The questionFull text in your LawHub copy of PrepTest 114

Reviewer: Although finalism—the view that there are purposes(48 more words not shown)

Which one of the following(16 more words not shown)

Reading the argument

A bad argument against an idea doesn't make the idea good.

The reviewer says finalism has been rejected by everyone, then describes a new book attacking it. The book misunderstands chance, so its criticism fails. Fine: we can accept that this book hasn't made its case. But what happened to every other reason people might have had for rejecting finalism?

Think of someone saying, “The sky is blue because Bob went to the store.” Bob's shopping doesn't establish the sky's color. Rejecting that ridiculous reason wouldn't establish that the sky isn't blue. A conclusion can be true even when a particular argument for it is bad.

What we’re looking for

The reviewer makes the same kind of jump, treating the failure of one attack as a reason to find finalism more plausible. For the parallel flaw, I want a rejected view, a defective argument against it, and an attempt to make the view seem more plausible because that argument failed. We don't need to decide whether finalism itself is true.

Working the answers

  • A

    The opening rejection is similar, but follow the evidence. A says the evidence supporting the single-author claim can be shown false. It doesn't identify a failed argument against that claim and then use the failure to defend the claim. The fact that dating results haven't been cited before isn't a defect in their reasoning. A's conclusion isn't reached through the same failed-attack move.

  • B

    This casts doubt on the dissenting botanists because they have spent little time studying the specimen. That may look like discrediting an opponent, but it doesn't identify a specific mistaken argument like the misunderstanding of chance. Also, most botanists already accept the identification, and the conclusion supports that prevailing view. The original uses a bad attack to revive a view that has been widely rejected. C reproduces those roles more closely.

  • C
    Correct

    The rejected view is that aluminum is as good as titanium for bicycle frames. That corresponds to finalism. The Ace engineer offers another argument against it, corresponding to the book's attack. His misunderstanding of pressure corresponds to the book's misunderstanding of chance.

    Then comes the same unsupported defense: because this engineer's argument is defective, the aluminum claim supposedly makes more sense than engineers believe. But titanium could still be better for other reasons, just as finalism could still deserve rejection for reasons this book fails to explain. Discrediting this one argument doesn't supply positive support for the view it attacks.

  • D

    This introduces an age difference between the wines and uses it to reject the prevailing ranking. It doesn't describe someone's argument against the prevailing view, expose a flaw in that argument, and use the flaw to support the view being attacked. A questionable comparison about wine age isn't the particular reasoning error we need.

  • E

    This is tempting because researchers' reasoning is criticized before the conclusion about television's harm. But the researchers' claim is that the parent-child relationship matters more, not that television cannot be harmful. Both influences could matter.

    The conclusion also restates the possibility the sociologists already accept, rather than reviving a rejected position. The original moves from general rejection to greater plausibility because of a failed attack. E doesn't preserve either the opposing positions or that shift.

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