Logical Reasoning

PT103 · S1 · Q24 That wall is supported by several

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That wall is supported by several joists.

Evidence

That wall has several joists. That wall has a bulge. The only thing that could have caused the bulge is a broken joist.

Conclusion (therefore)

Thus, there is at least one broken joist.

Evaluate

The main action of the logic here is the conditional, triggered by the fact.

The conditional (signified by 'the only', which is a sufficient - left side - indicator) looks like this:

Wall bulging → broken joist

The argument establishes that the wall is bulging and then validly concludes that there is at least one broken joist.

Goal

We could itemize the entire argument: P1: That X has several A's. P2: That X is Y. P3: Y → bad A. C: some bad A's.

But mainly I would be caring that there's a conditional premise, a factual premise that triggers it, and a conclusion that factually declares the outcome of the conditional.

24.

Which one of the following arguments is most similar in its logical features to the argument above?

  1. Correct

    At least one of the

    Why this is right

    This supplies a conditional: conductor grimaces → some made mistake It establishes that the conductor just grimaced (the trigger), and then it concludes that someone made a mistake (the outcome). Both the original and this answer embedded both the conditional and the fact in the same claim. If I say, "it would be impossible for me to be having the great time I'm having if Kevin weren't here", that both reveals a conditional rule (have this great a time → Kevin here) and it factually reveals that I'm having a great time. That's not an important logical feature. We essentially find the logic of the argument the same even if the conditional and the trigger-fact were two separate claims. It just happens to be a similarity they both have.

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

    71% picked this

  2. The first piece must have

    Bad Conclusion Match

    We can tell that this conclusion is not just concluding the outcome of the conditional in the premise, because it contains an idea "the easiest" that wasn't in the premise. In fact, the "conditional" in the premise isn't a timeless rule like - the only thing that can cause a bulge like that is a broken joist - the only thing that can make the conductor grimace like that is a mistake This is giving more of a historical conditional: if it was a piece where → then it was there weren't many mistakes the first piece Either way, the argument does not establish the trigger and then conclude the outcome of that conditional. It introduces a brand new idea, "easiest", in the conclusion.

    4% picked this

  3. The players play well only

    Bad Conclusion Match

    The conclusion here is the first claim. The "since" attached to the second claim indicates that it's providing support (FABS: for, after all, because, since). This conclusion is conditional, "only when". The original conclusion was just factual, "at least one joist is broken". That mismatch is grounds for elimination.

    3% picked this

  4. One of the orchestra’s players

    Bad Evidence Match

    There's no conditional premise. It's just a fact that the composer specified that a harp should be played. So there's no way to mimic the original argument of factually establishing the trigger and then concluding the outcome.

    17% picked this

  5. The emotion of the music

    Bad Conclusion Match

    The conclusion here is the first claim. The "since" attached to the second claim indicates that it's providing support (FABS: for, after all, because, since). This conclusion is conditional, "the only". The original conclusion was just factual, "at least one joist is broken". That mismatch is grounds for elimination.

    5% picked this

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