I'm honestly not entirely sure how it happened. [He laughs a little, sheepishly.] I simply woke up one day and... I could. Someone who can look in people's minds examined me, because I thought I was going insane, and they said that someone or something had forcefully put the knowledge there.

Sabriel thought it might have been one of the turtles, in my dreams. But I've never been able to confirm it.