by ohthatpatrick Sat Jun 09, 2012 1:36 pm
Let's identify the argument core real quick:
prem 1 - there's less plastic trash than paper trash (whether we measure by weight or volume)
prem 2 - the environmental damage of plastic trash is roughly equal to that of paper trash
conc - thus, the current use of plastics actually does environmental harm than the current use of paper products.
If we had concluded
thus, plastic trash currently does less environmental harm than paper trash, this argument would actually be pretty airtight.
But by concluding that the use of plastic does less harm, we've gone beyond the scope of our trash-based evidence.
(Yes, I just wanted to say 'trash-based evidence').
So, even though we have to accept plastic trash does less harm, it could still be true that the use of plastic (meaning everything about its life cycle) is more environmentally harmful than the use of paper.
(A) has a couple problems. First of all, it tells you something potentially bad about paper products, but it doesn't mention plastic products. If an argument is trying to conclude that "X is better than Y", then you can never really strengthen or weaken that argument with an answer that just says "X has a bad quality" or "Y has a good quality".
How do I know that plastic products don't also increase in volume after manufacture and before being discarded as trash?
In order for an idea to strengthen an "X is better than Y" type claim, you have to know "X has a good quality that Y does not have". (Conversely, to weaken it, you need to know "X has a bad quality that Y does not have")
The other problem with (A) is that it doesn't seem to tell us anything new, that's relevant to judging "current use of plastics vs. current use of paper". (A) is saying that paper products may get bigger between when they're made and when they're trashed.
Well, our evidence already dealt with them when they were trash, so that process of "increasing in volume" is already done by the time we measured them.
If you're thinking that (A) strengthens the argument by convincing us that there is a lot a paper trash, remember that we don't need to be convinced of the premises. We were already told that there's more paper trash than plastic trash. We don't need to strengthen the premise. We need to strengthen the conclusion (or the assumptions that connect the premise to the conclusion).
===other answers===
B) it's totally irrelevant what popular opinion believes, since our conclusion is about reality, not perception.
C) discussion of other types of trash is totally irrelevant to the claim of which is doing more harm: the use of plastic or the use of paper.
D) This strengthens by ruling out an objection. Someone might have objected to the original argument, "Sure, plastic TRASH does less harm than paper TRASH. But the manufacturing process for plastic does way more environmental harm than the process for paper." This answer choice rules out that concern by saying, "No, even the PRODUCTION process is worse for paper."
E) The changing regional proportions doesn't make any difference. Our premises provide us with aggregate, national statistics and our conclusion is about "nationwide".
Hope this helps. Let me know if you had a different way of making (A) strengthen.