So I said, "" Well, how long did you practice on it before you decided you understood nothing? "" They said, "" We look at it every day. "" So I said, "" For two months, you were looking at stuff you didn't understand? "" So a 12 year-old girl raises her hand and says, literally, "" Apart from the fact that improper replication of the DNA molecule causes genetic disease, we've understood nothing else. "" (Laughter) (Applause) (Laughter) It took me three years to publish that.