And at the end of that lecture, Keltham said, smiling, that, if anybody here had managed, somehow, not to process all of that, they should know with dread in their hearts that it'll probably come to visit them during their next Owl's Wisdom. And every time that thought occurs to them, while waiting for their next Owl's Wisdom, even if they see themselves looking away from that thought, they should know then that it's definitely coming for them.
That's how Peranza ends, at Keltham's hands, who thought he was joking.