“You touch it, and pay attention and learn what it is, and then you have the outside of it, and then you can work on the inside of it.

“It's easier to claim and keep stuff that doesn't have much structure. That's why glass is useful. Here, you can have some of mine to start with; it won't be any harder if I'm not opposing you, and you need some more practice material that is simpler than a pencil.”

He picks up a blob of glass that rises out of the puddle, and hands it to her. It displays no inclination to gloop in her hands.