Logical Reasoning

PT10 · S4 · Q18 Advertisement: Attention pond owners!

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Advertisement: Attention pond owners!

Conclusion (so)

By using BTI regularly to destroy mosquito larvae, you can reduce the populations of hatching mosquitos w/o diminishing the populations of fish / frogs / good insects.

Evidence

98% of mosquito larvae die within minutes, after being treated with BTI.

Evaluate

The evidence does a decent job convincing me that BTI will help reduce the mosquito population, as long as we assume that less than 98% of larvae die within minutes when a pond isn't treated with BTI.

But where did all these other promises come from about fish / frogs / good insects?

Goal

The ad is assuming that a 98% death rate is better than normal, and it's assuming that BTI does not have adverse effects on the local fish / frog / insect population. (Maybe some of them will be bummed that the mosquitos are gone, if that was their primary food source)

18.

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

  1. The most effective way to

    Too Strong: most effective

    The ad doesn't need to assume that BTI is the best way to control mosquitos. It doesn't promise that it's the best, only that it will greatly reduce mosquito populations.

    18% picked this

  2. Populations of mosquitoes are not

    Irrelevant Quality: dependent on single body

    This answer has a very appealing ruling-out "not", so we would negate it and see if it weakens. Would it hurt the argument if we say that populations of mosquitoes ARE dependent on a single body of water? No that doesn't seem to hurt in any way. This ad envisions that we will treat our one body of water (our pond) with BTI, so it seems like if anything the negation is very compatible with the argument.

    2% picked this

  3. There are no insect pests

    Out of Scope: other pests

    This ad just promises that BTI would reduce mosquitoes. The fact that mosquitoes are the only pest mentioned doesn't mean that the argument is assuming that mosquitoes are the only pest that pond owners might want to eliminate. A tutor who only offers services to tutor people in LSAT games isn't assuming that there are no other sections of the test that people might want help with. They're just only offering help with one section.

    5% picked this

  4. The effectiveness of BTI in

    Irrelevant Quality

    This also has the lovable ruling-out "not", so we'll see if the negation would weaken. Does it hurt the ad to say, "the effectiveness of BTI does require strict adherence to specific application procedures"? No, as long as people adhere to the procedure, the conclusion would still be correct to say that by using BTI regularly, you can greatly reduce mosquito populations.

    2% picked this

  5. Correct

    The fish, frogs, and beneficial

    Why this is right

    Since this has the Defender style "not", we'll negate it and see if it weakens. Does it hurt the argument to say that fish, frogs and beneficial insects DO depend on mosquito larvae for food? Yes! This would attack the truth of the conclusion. If fish, frogs, and insects depend on larvae for food, then greatly reducing larvae for greatly reduce the food supply they depend on, so it very possibly could diminish the populations of fish / frogs / insects.

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

    73% picked this

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