The scene: Ethan’s room. Ethan and Jack have just finished a game of chess on Jack’s phone. It is past bedtime. Jack gets up to leave.

Ethan: I’m really scared about the dark. I’m scared about monsters.

Jack: Well, there is a light on in the bathroom. You can see everything in here so it’s not dark.

Ethan: No, when I close my eyes I can see monsters and I don’t want them to come in.

Jack: Ethan, our house is all locked up. You are safe in this house. There is no way for a monster to get in the house.

Ethan: Yes it could. It could come down the chimney.

Jack: A-ha! There’s a flue in the chimney that’s closed so monsters could not come down the chimney.

Ethan: What is a flue?

Jack: A flue is a big piece of steel that closes off the chimney.

Ethan: What is steel?

Jack: Steel is a very hard metal that they make cars out of. Plus, our chimney is about this small (gestures with hands) so a monster could not fit in there anyway. And even if there were a small enough monster, he wouldn’t be able to get past the steel flue.

Ethan: Not if he has a laser to cut it with.

Jack: Well if he has a laser cutter, he would need a whole bunch of batteries to power it, and then he certainly wouldn’t be able to fit through the chimney with all those batteries.

Ethan: He would just go home and get new ones and put them on his belt.

Jack: Ethan, you know lasers are just light, right.

Ethan: Yes.

Jack: And to have a strong enough laser to cut through steel, you would need as many batteries as would fit in your bathroom. You need that many to power a laser cutter. They DO make laser cutters, but they require plugging into a wall.

Ethan: What if he snuck into the house and plugged the laser cutter in?

Jack: How is he gonna sneak in the house? The house is locked up and he can’t get past the flue.

Ethan: Oh.

Jack: Good night, Ethan.

Ethan: Good night, Daddy.