Q4 - In an attempt to counter complaints

[ohthatpatrick]

Question Type:
Weaken

Stimulus Breakdown:
Conclusion: This pesticide would not harm humans if absorbed into edible plants.
Evidence: Ounce for ounce, the activite ingredient in the pesticide is less toxic than the active ingredient in mouthwash.

Answer Anticipation:
We're assuming that mouthwash is not hazardous to humans. We're also assuming that the amount of the pesticide you'd ingest by eating plants treated with it is close to the amount of mouthwash you ingest. Even though the toxin in alcohol is, ounce for ounce, less toxic than the toxin in arsenic, I could still harm myself by ingesting enough alcohol. Similarly, this pesticide could still be harmful if humans absorbed enough of it.

Correct Answer:
B

Answer Choice Analysis:
(A) We don't care about comparing mouthwash to other human products.

(B) Yes! This sounds like the pesticide would be more harmful than mouthwash. It addresses the TOTAL quantity of toxins consumed, as opposed to the way less relevant measurement of toxins per ounce.

(C) This has no connection to the evidence about mouthwash, so this isn't weakening the reasoning in the argument. It DOES make it sound like the pesticide's packaging acknowledges the potential hazard to humans, but the package is probably referring to the danger of getting the pesticide directly into your mouth (not the danger of eating plants that were treated with this pesticide).

(D) This would strengthen, since it makes the pesticide sound LESS harmful than mouthwash.

(E) This doesn't help us evaluate the mouthwash vs. pesticide claim.

Takeaway/Pattern: Like most correct answers to Weaken, this allows us to say "your evidence is true, but I can still arrive at the opposite conclusion". "Pesticide has less toxin ounce for ounce, but since you ingest more toxins total with pesticide than with mouthwash, it's still possible that pesticides pose a hazard to humans".

#officialexplanation

[WaltGrace1983]

This is a weaken question.

Ounce-for-ounce the ingredient in pesticide is less toxic than the active ingredient in mouthwash
→
Pesticide is not (it is defensible to think that its not) hazardous

Once I see that phrase, "ounce-for-ounce," I automatically know what I am going to be attacking. There is a really similar question in another PT (forgot which one) that uses this same exact phrase I do believe. The problem with this argument is that it assumes that there is a pretty equal ingredient of pesticide in the plants as there is ingredients in the mouthwash. The argument also forgets that, you know, you SPIT OUT the mouthwash.

I have seen this kind of error many times before on the LSAT. It gives you a premise about quantity and then applies to a conclusion about value: "The amount of cholesterol in a tablespoon of this coffee lightener is the same as the amount of cholesterol in this other coffee lightener: they must give you the same spike in cholesterol from ordinary use!" The problem is that we have no idea about how much coffee lightener (or in this case, pesticide) is going to be applied! In order to weaken this argument, we should show that there is much more pesticide being ingested than mouthwash being ingested.

(B) does exactly this.

[wxpttbh]

Can anybody explain why D is wrong?

[JonA716]

I just want to say - after 20+ years, this post has not been corrected...