Logical Reasoning

PT117 · S2 · Q22 All the evidence so far

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All the evidence so far gathered fits both Dr. Grippen’s theory and Professor Heissmann’s. However, the predictions that these theories make about the result of the planned experiment cannot both be true.

Conclusion (therefore)

The result of this experiment will confirm one of these theories at the expense of the other.

Evidence

The predictions that Dr. Grippen's theory and Prof. Heissmann's theory make about the result of the planned experiment cannot both be true.

Evaluate

Given that both predictions can't be right, why is it flawed to say that the experiment will show that one of them is right and one of them is wrong?

Because, they could both be wrong!

If you think Oprah is 65 and I think she's 70, we can't both be right. But when we ask the internet what her age is, that doesn't guarantee that one of us is right. We might both have predicted the wrong number

Goal

Look for an answer vulnerable to a similar objection of, "Couldn't they both be wrong?"

Structurally, it'll probably resemble: - X and Y have incompatible predictions when it comes to Matter A. - Matter A will soon be resolved. - Thus, we'll soon know that either X or Y is correct and the other is wrong.

22.

The argument above exhibits an erroneous pattern of reasoning most similar to that exhibited by which one of the following?

  1. David and Jane both think

    Bad Conclusion Match

    Without even reading the whole answer, we can peek at the conclusion and see it's a poor match for the original. The original conclusion is, "One will be right, and one will be wrong", which is why we have our objection of, "Wait ... couldn't they both be wrong?" But we couldn't make that objection to this conclusion, because saying "at least one of them is wrong" is allowing for the possibility that they're both wrong.

    18% picked this

  2. Although David thinks the tree

    Bad Conclusion Match

    Without reading the whole answer, we can peek at the conclusion and see it's a poor match for the original. The original conclusion is, "One will be right, and one will be wrong", which is why we have our objection of, "Wait ... couldn't they both be wrong?" This conclusion isn't saying anything about right / wrong, or correct / incorrect. It's just concluding, "so, this prediction is incompatible with that prediction". That's a match for our premise, not for the conclusion.

    5% picked this

  3. David and Jane have been

    Bad Conclusion Match

    This conclusion is a conditional claim, "If elm, then David is more right". The original conclusion is, "One will be right, and one will be wrong". It wasn't conditional, and it didn't favor either of the two parties.

    10% picked this

  4. David thinks that there are

    Weak Conclusion Match

    This conclusion is saying, "We'll find out whether this one person was right or wrong." The original conclusion is, "One person will be right, and the other person will be wrong", which is why we have our objection of, "Wait ... couldn't they both be wrong?" But we couldn't make that objection to this conclusion, because saying "couldn't David be both right and wrong?" is a silly objection. Given that Jane's position is "David is wrong", it is fair to say that finding out David is right or wrong does simultaneously tell us whether Jane was right or wrong (her correctness is inverse to his). But again, the objection of "couldn't they both be wrong" does not apply, because there are binary options. David is right, and thus Jane was wrong. or David is wrong, and thus Jane was right. It's impossible for David to be wrong and thus Jane to also be wrong.

    12% picked this

  5. Correct

    David thinks this tree is

    Why this is right

    This conclusion, like the original, is saying that an upcoming measurement / test / evaluation will show that one person was right and one was wrong. David and Jenn have incompatible predictions, just as Dr. Grippen and Professor Heissmann had. Those predictions will be put to the test by an upcoming thing (either Maria's expert analysis or the results of a planned experiment). The argument is fallaciously concluding that one person will be vindicated and the other person shot down, but in both cases we can make the objection, "Couldn't it turn out that both parties are wrong?" Maybe Maria is going to tell us that this tree was neither beech, nor elm. Maybe the results of the planned experiment will not match Dr. Grippen's or Professor Heissmann's predictions.

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

    56% picked this

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