Logical Reasoning

PT131 · S1 · Q2 We already knew from thorough

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We already knew from thorough investigation that immediately prior to the accident, either the driver of the first vehicle changed lanes without signaling or the driver of the second vehicle was driving with excessive speed.

Conclusion (so)

2nd driver wasn’t liable for the accident.

Evidence

Accident was caused by 1st driver changing lanes without signaling or by 2nd driver speeding. Either action would make a driver liable. We now know that 1st driver changed lanes without signaling.

Evaluation

How could we accept the evidence but still fight that conclusion and say that the 2nd driver is liable? We could just say that he was speeding.

In life, sometimes we hear an either/or and assume it’s one or the other, but not both. In LSAT, we need to be told explicitly that it can’t be both. Otherwise, our default understanding of “Either X or Y is true” is that “X is true, Y is true, or both”.

The author is getting caught up in a False Choice, that either driver 1 or driver 2 is liable, but not both. However, it’s possible that both drivers are liable, so we need to know whether the 2nd driver was speeding.

Goal

Was the 2nd driver speeding?

2.

Which one of the following would be most important to know in evaluating the conclusion drawn above?

  1. Correct

    whether the second vehicle was

    Why this is right

    If the 2nd driver was speeding, then he is also liable. If we wasn’t, then the author’s conclusion is probably correct.

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

    88% picked this

  2. whether the driver of the

    Irrelevant Distinction: "aware vs. not aware"

    We don’t care whether the driver was aware of not having the signal on. The legal definition for liability doesn’t say anything about awareness. As long as we know 1st driver changed lanes without signaling, we know she is liable.

    4% picked this

  3. whether any other vehicles were

    Out Of Scope: “other vehicles”

    The conclusion is assessing whether or not the 2nd driver is liable. Whether other cars were involved is irrelevant to that assessment (because more than one car can be liable).

    0% picked this

  4. whether the driver of the

    Out Of Scope: “reliable witness”

    The 1st driver’s testimony only concerns whether she switched lanes. If she’s unreliable, then maybe she didn’t switch lanes. But that would still have no impact on whether the 2nd driver is liable, because ascertaining that revolves totally around whether that driver was speeding.

    1% picked this

  5. whether the driver of the

    Irrelevant Distinction

    Irrelevant Distinction: "noticing vs. not noticing turn signal" In assessing the 2nd driver’s liability, all we need to know is whether or not she was speeding. It’s irrelevant whether she would have noticed a turn signal, in this hypothetical world.

    6% picked this

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