- Wed Aug 15, 2018 1:01 pm
#49609
Hi, Manchas,
This is not so much a change in the LSAT per se. It has always been possible to attack the integrity of the data offered in support of a conclusion. You are likely familiar with this happening all the time with surveys and samples used as premises. "Yes, it's true you have a survey, but it sucks."
In arguments with subordinate conclusions which are in turn used as premises for a main conclusion, it is possible to attack a fallacy that leads to the subordinate conclusion, thus calling into question the entire argument.
Overall, you are correct that we cannot flat out say "your premise did not happen," but we can call into question an underlying assumption behind the premise, thus attacking its integrity. This is what happens here. If we know the schedule is far easier to adhere to, then we have some reason to believe people may put out a greater volume of recyclables overall.
In addition, the validity of this approach to weakening the problem is heightened by the fact that we have two competing presuppositions in this argument. On the one hand, the city claims there will be more recyclables. On the other hand, the editor claims there will not be more recyclables. Who is right? We need to have some evidence to determine whose speculation is correct.
Thus, we essentially have two competing claims and no reason in particular to trust the editor's speculation more than that of the city. With the additional evidence in answer choice (D), we have good reason to go with the city over the editor, which is what we want to have happen here.
I hope this helps!