Logical Reasoning

PT141 · S4 · Q26 Farmer: Crops genetically engineered

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Farmer: Crops genetically engineered to produce toxins that enable them to resist insect pests do not need to be sprayed with insecticides.

Evidence (Since)

Too much insecticide has harmed the wildlife that live near the crops.

But ... we have new GMO crops that you don't need to spray with insecticide.

Conclusion

Using GMO crops more would be good for wildlife near crops.

Evaluate

This makes sense, superficially. If insecticides were harming wildlife, then GMO crops with no insecticides should be better, right?

This is an Incomplete Comparison.

When an author is pitching a Plan, she's implicitly making a comparison between the Current World and the hypothetical Plan World.

When we go from normal crops to GMO crops, one difference is that with the GMO crops won't need insecticide.

But there could potentially be other differences. How could the Plan fail to achieve its Goal?

We grow more GMO crops (w/o insecticide), but it doesn't help the local wildlife to recover.

What if people don't want to buy the GMO crops? Would the farms go out of business? Maybe, but the conclusion is only making a claim about the effects of GMO crops on helping wildlife to recover.

If farms went out of business would that negatively impact local wildlife? Would something else about GMO negatively impact local wildlife?

Goal

Find an answer that, when negated, sounds like a way to argue that this plan, if enacted (doing more GMO crops), wouldn't help wildlife to recover (maybe would even be harmful to them).

26.

Which one of the following is an assumption the farmer's argument requires?

  1. Correct

    Use of the crops that

    Why this is right

    This correct answer is a language connector (Missing Link) between the premise and the conclusion. Premise: the GMO crops don't need insecticide Conclusion: the GMO crops will let wildlife recover This answer is essentially saying, "If we use the GMO crops instead of the insecticide-laden normal crops, it'll be better for the local wildlife." If we negated this, it would be saying, "Using the GMO crops will cause at least as much harm to local wildlife as the normal crops w/ insecticide do." That would blow up the conclusion. The correct answer, when negated, just has to weaken, but in this case it pretty much contradicts the conclusion. Generally, there are three ways to feel about a correct Necessary Assumption answer, and this is the 3rd way (the least common). 1. This answer is right, because the author did make a move from this concept to that concept. 2. This answer is right, because if we negated it, it would weaken. 3. This answer is right, because the author was clearly thinking this.

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

    52% picked this

  2. Wildlife populations that have been

    Too Strong: even slightly / likely

    The author's conclusion is more squishy than this level of precision. She's saying "using it more widely" is likely to help. As we use GMO crops more widely, the amount of insecticides on those newly switched crops are reduced completely, not slightly. When we switch from traditional crop to GMO crop, we turn pesticides down to 0. The author is predicting that turning some croplands down to 0 pesticides will likely help wildlife recover. We don't know that she clearly thinks even a slight reduction in pesticide would lead to recovery.

    21% picked this

  3. Crops that have been genetically

    Too Strong: never

    The author doesn't have to assume pesticides are never used on GMO crops. She's just assuming that as these GMO crops would increase in usage, some if not most of them would be pesticide free. When you negate "never", you get a puny objection of, "Hey, author, there was at least one time when someone sprayed pesticides on GMO crops".

    15% picked this

  4. Use of crops that have

    Out of Scope: cost

    The issue of cost is out of scope, because we're only analyzing what effect this switch would have on local wildlife populations' recovering.

    3% picked this

  5. If a wider use of

    If-Conclusion

    The "if" part of this conditional is the argument's conclusion. That is always wrong. (The "if" part can be the negation of the conclusion) An author's argument is only trying to get to its Main Conclusion. That's the final destination. The truth value of the claim in the Conclusion is the only verdict we're interested in. Any answer saying "If Conclusion, then ..." is wrong since it's saying the author made a move from the conclusion to something else. It's either gonna give us an Illegal reversal, going from Conclusion to Evidence, or it's just going to give us some bogus extra move, as this answer does. The author doesn't need to assume that the benefit of GMO crops is only the pesticide thing. If you negate that answer and say, "Hey, author, the local wildlife from the GMO crops in another way too", it only strengthens the likelihood of her conclusion being true.

    9% picked this

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