by bbirdwell Wed Dec 29, 2010 2:48 pm
Well, by emphasizing the "however" statement, you're on the right track, but we need to be clearer about the argument itself.
You actually made a reasoning mistake that led you to the correct answer. The argument never says that Stoker was the first, and it's key that we recognize this.
Here's what the argument actually says:
1. Stoker's book had pervasive influence
2. because of this, people think turning into bats is essential to vampire myths
3. (conclusion) This is wrong. In other words, "Turning into bats is NOT essential to vampire myths." (this re-wording is essential, i think, to clearly understanding the argument)
4. this is so because vampire myths existed before Stoker's book.
Consider that argument in a nutshell: Turning into bats is NOT essential because vampire myths existed long before.
What's missing from that argument? Where's the gap?
The conclusion itself is about bats, and the key evidence is about the age of other vampire stories.
So what's got to be true about all those other stories in order for this conclusion to work? They better have something to do with bats.
Consider this: what if every single one of those stories talks about vampires turning into bats? Ah. That would make the conclusion look stupid. Therefore, the author must be assuming that at least some (one) of these older stories DO NOT talk about turning into bats.
(D) says this in a typically awkward LSAT way. The construction "at least one...did not" is the tipoff. The author MUST assume that AT LEAST ONE of those old stories did NOT talk about turning into bats. Otherwise, the conclusion is completely ludicrous.