The problem, Brodie says, is that the cause of seizures in individual patients is most often unknown. "Epilepsy is like a whale", he says, "you see the spouts [the seizures] but you don't see the whale [the cause]. Sometimes you see a bit of the whale; sometimes it breaches, and you see a bit more of the whale. But what we have is anti-spout drugs, we don't have anti-whale drugs".