Logical Reasoning

PT109 · S1 · Q6 A recent national study of

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A recent national study of the trash discarded in several representative areas confirmed that plastics constitute a smaller proportion of all trash than paper products do, whether the trash is measured by weight or by volume.

Conclusion

The current use of plastics actually does less harm to the environment nationwide than that of paper products.

Evidence

Plastics represent a smaller proportion of all trash than paper, and the damage to the environment done by a given unit of plastic trash is about the same as that of paper trash.

Evaluate

At first, this conclusion might seem relatively airtight. If there's less plastic trash than paper trash, and a kg of plastic trash does about the same environmental harm as does a kg of paper trash, then isn't it fair to say that currently plastic is doing less harm than paper?

Yes, it is fair, as long as we say

Where the conclusion creates some wiggle room of doubt is by talking about the current use of plastic vs. the current use of paper. That brings in a whole bunch of other considerations: - does it hurt the environment more to make plastic? to transport plastic? to sell plastic? - once in the hands of consumers, do people ever use plastic in a way that hurts the environment?

Goal

Given that we know that plastic gets the win when comes to environmental harm of trash, the remaining areas to strengthen this argument would be saying that the environmental impact of plastic beats out (or ties) paper in some other aspect of their life cycle:

Harnessing raw materials -> manufacturing -> distribution -> sale -> consumer use -> trash.

If plastic ties paper in any of these categories, it still strengthens the argument because it rules out a possible objection that

Which one of the following, if true, most strengthens the argument?

A given weight of paper
No Impact
The premise we have about the environmental impact of trash says that "whether we measure the trash by weight or volume, the damage is roughly the same". At this point, the phenomenon being described in this answer choice has already occurred. We can't pick this answer by saying, "check it out, the paper trash is even worse than you think --- it actually grows over time." It grows over time before being discarded as trash, so this doesn't impact our current assessment of paper trash.
10% picked this
According to popular opinion, volume
No Impact: popular opinion
LSAT does not put any factual weight behind public opinion. If an argument is discussing how the public feels about something than public opinion can be relevant, but if an argument is discussing what is factually the case, then public opinion is pretty meaningless, unless it's somehow established that the public is accurate on this matter. Beyond that easy/quick way to disqualify this answer, the idea itself makes no difference. Since the argument said "whether you measure by volume or by weight", the argument is totally indifferent to which one we do. So introducing public opinion that thinks "doesn't volume matter more?" is almost going against what we were presented with so far.
3% picked this
The sum of damage caused
No Impact: comparison to other trash
The conclusion is a comparative claim about "use of plastic vs. use of paper". It doesn't make a difference whether plastic and paper are the top 2 threats to the environment or the 99th and 100th worst threat. All we're analyzing to judge this conclusion is a head-to-head comparison between plastic and paper. Any other sort of trash has no bearing on who wins/loses between plastic and paper.
3% picked this
Correct
The production of any paper
Why this is right
This establishes that plastic wins in a 2nd category of its overall use. We already knew that plastic trash was doing less environmental harm than paper trash. This answer adds on that plastic manufacturing is also doing less environmental harm than is paper manufacturing. Had the reverse been true, this would have been a great objection. We could have said, "Sure, plastic trash does less harm than paper trash. But we can't say the current use of plastics does less environmental harm since the production of plastic is so much worse for the environment than is the production of paper."
Skill tested: Strengthen · how this choice captures the argument's function is the move to repeat next time.
83% picked this
The proportion of plastic trash
Wishy-Washy / No Impact
We need a fun nickname for this common type of Strengthen / Weaken answer choice: - things vary - things fluctuate - there are differences here and there Cool? This muddy, nonspecific type of idea doesn't have any clear impact. In the case of this argument, we certainly don't care whether proportions vary from one part of the country to another (we certainly would have assumed that's the case). The argument relies on a national study of several representative areas, so it should give us an accurate picture of the aggregate national picture of plastic trash vs. paper trash. We trust national polls to give us an accurate picture of the national electorate, even though the proportion of liberal voters to conservative voters varies quite a bit from one part of the country to another. That's because we trust that qualified pollsters are using representative samples to reflect this variety.
1% picked this

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