[ferno]

In Walden, Thoreau muses: "How many a man has dated a new era in his life from the reading of a book?"

You know what I mean, those books that empty all the cobwebs out of your brain, or give you a violent but necessary knock on the head. Which books did that for you guys?

For me it was Montaigne's Essais. I don't recognize the person I was when I first picked up that book.