Because I can look up from Catching Fire (which finally came in at the library, yay!) and say, "You know when not to use 'which begs the question', right?" and Scott not only says "Yes" but engages in a detailed discussion of the topic which leads me to a fuller understanding of the actual meaning of the phrase. (I can easily identify when it's being used incorrectly, but there aren't many everyday contexts in which it can be used correctly so I'm not as familiar with that usage, sadly.)
For anyone who has no clue what I'm talking about: Professor Wikipedia will teach you.