by noah Fri Aug 20, 2010 10:20 am
The key to these problems is knowing how to "reverse" statements that say "some X are Y." Let's start with what we DON'T know: If we know that some dogs are cute, we don't know that some dogs are not cute. On the LSAT, "some" means 1 or more - it is possible that "some" is referring to all. It would be correct to say "some of the letters in the alphabet are on a standard keyboard."
What we would know from the given dog statement is that some cute things are dogs. It seems almost too obvious, but that's all we can infer.
In this question, we're told:
Some academic essays are impossible to comprehend, and some essays that are impossible to comprehend should not be read.
The correct answer to this: Some essays that should not be read cannot be comprehended simply reverses the second some statement.
The wrong answer - Some academic essays should not be read - plays on our desire to combine the two sentences. However, here that's not really possible. If we know that some apples are rotten and that some rotten fruit is under the couch, do we know that there's a rotten apple under the couch? There might be, but it also might be a rotten watermelon. Same thing here - some academic essays are incomprehensible, but maybe those incomprehensible ones are not the ones that should not be read. Maybe it's only the incomprehensible political essays that should not be read and all the incomprehensible academic ones really should be read!
Tell me if that clears it up. - N