As per ur wrds,If we negate the assumption on which the conclusion is made,that serves the purpose of weakening the argument...
Hi gmatmachoman,
that's not quite what I meant.
In a weaken question, an answer choice that completely negates the assumption is definitely a weakener.
BUT, in order to weaken an argument, an answer choice does not necessarily HAVE to
negate the assumption, and nor will it be likely to.
("Negate" = "Deny" = remove from existence).
The right answer DOES have to
attack the assumption--tend to refute it. This is because the definition of weakening is: making an argument less likely to be true. (However, the weakener will almost always
clearly target the assumption.)
The reason I used negation test in my explanation above was a little bit different from usual. Because the argument was difficult, and because it may have been a bit tough to identify the assumption, I pointed out that we could make of use the denial test as a check (to verify) that you have identified the correct assumption.
In other words, you can, if you want, figure out the assumption, and then use denial test to verify it in your head before you look at ANY answer choices.
After I finished doing that, my prediction was this: "The author is assuming that naturally occuring fullerenes are just ike the lab ones--they need unique conditions to come about. Because this is a
weaken question, I will aggressively scan for a fact that will
attack this assumption."
Kaplan Teacher in Toronto