Logical Reasoning

PT155 · S1 · Q1 Advertisement: Omnicide kills more

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Advertisement: Omnicide kills more species of insects than any other insecticide.

Conclusion (so)

Omnicide is the best insecticide for home gardeners, especially gardeners who cannot determine which insects are destroying their plants.

Evidence

Omnicide kills more species of insects than any other insecticide.

Evaluate

Given that ... omnicide kills more species of insects than any other insecticide, How could we argue that ... a gardener who isn't sure which insects are destroying their plants should not consider Omnicide the best choice?

We could say, .

If the author is comparing Omnicide to all other insecticides on the market, then she's assuming that when you weigh all the pros and cons, Omnicide has the best net value.

Goal

Look for an answer saying something bad about buying Omnicide or something preferable about buying one of its competitors.

Which one of the following, if true, most weakens the reasoning in the advertisement?

Some of Omnicide's competitors kill
No Impact
This is saying that one of the competitors is almost as good as Omnicide when it comes to one good thing we know about Omnicide (kills the most types of insects). Since the competitors are almost as good, they're still not as good as Omnicide, so this doesn't go against the author's claim that Omnicide is the best option.
4% picked this
Correct
Many insect species are beneficial
Why this is right
This points to a bad thing about Omnicide -- it will kill most of the insect species that are beneficial to garden plants. Since this is a negative thing about Omnicide, and since we can presume that other insecticides would have less of this negative (since they kill a more limited spectrum of insects), this hurts the author's claim that Omnicide is the best option. Sure, it might kill the mystery insects that are messing up the garden, but it will also kill most of the beneficial insects that are helping the garden, so the garden may end up worse off overall.
Skill tested: Weaken · how this choice captures the argument's function is the move to repeat next time.
92% picked this
Merely protecting plants from attack
Too Weak / No Distinction
This is incredibly weak (X does not guarantee Y), and weak answers are almost always wrong on Strengthen, Weaken, Paradox, and Sufficient Assumption. Scoring a 180 does not guarantee you'll get into Harvard. Does that mean a 180 isn't the best score you can get? Of course not. So saying that "killing off all the pests doesn't guarantee healthy plants" doesn't in any way indicate that "killing off all the pests isn't the best strategy". This answer is just acknowledging you also need to give your plants light and water. Merely protecting them from pests isn't enough. This answer also provides no distinction between Omnicide and other pesticides, all of which are designed only to protect against pests., so it wouldn't provide a reason for thinking Omnicide isn't the best choice.
2% picked this
Omnicide is more profitable for
No Impact
The fact that the company who makes Omnicide has a higher profit margin on this insecticide than it has on other insecticides they make has nothing to do with a consumer's decision about whether Omnicide is the best option for their garden.
0% picked this
Omnicide does not kill weeds
No Distinction / No Impact
Similar to (C), this conveys the idea that an insecticide is not a cure-all. You still have to worry about food, water, sunlight, weeds, and mammalian pests. But all we're doing here is picking an insecticide. The job of an insecticide, as the name suggests, is to kill insects. We wouldn't hold it against Omnicide (or any other insecticide) that it's fails to kill weeds and mammals. This answer, like (C), would apply equally to all insecticides, so it doesn't give us a reason to choose an insecticide other than Omnicide.
2% picked this

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