"It's really pretty!" says Matilda. It is indeed really pretty.
"Congratulations!"
"So what sorts of things can mages do, besides put out burning buildings?"
"I would not like to teach ialdae that part. That would be really inconvenient! And scary!" says Matilda. "But I might want to teach it the other stuff."
"I don't know. I don't exactly know how I'd try. But so far I think ialdae has been very good about only learning nice things when I'm the one teaching it."
"Well, I guess it's getting niceness from me," she says. "Because when I teach it, it learns nice things, and when Miss Trunchbull taught it, it learned bad things instead. As long as nobody tries to teach it bad things, maybe it will keep learning just the nice ones."
"It hasn't done that with wizardry, though. And it didn't really do it with lights either, it picked up the sparkly healing ball but not all of its limitations. What kind of dangerous wizardry stuff is there?"
"I wonder," muses Matilda, "if I could teach ialdae to do magic that doesn't really exist, out of books and things. I think maybe I can. I'll try it."