A magician who purports to be from the future is making bold claims. Asking for a volunteer, he offers the following prize to anyone who comes on stage:

"Im going to hand you a box that has you inside it!"

"Either that, or I'll give you the address of a place with a magical time travelling portal."

Being questionably brave, you volunteer and walk onto the stage. The magician hands you your prize--a large cardboard box. Noting your skepticism, he adds, "You can open it anywhere, and you'll be inside."

You decide to take the box home. Its much too light to have anything in it, let alone yourself! You open the box and look inside, wondering what sort of gag he has planned. But suddenly you find that the box has disappeared, and you're standing on stage waiting for him to tell you what you've won, again.

"The address of the time-travelling portal is," he begins, rattling off your home address.

You are startled that he could have known your address, but when you later arrive home, you see an open cardboard box waiting. Is this supposed to be the portal? Knowing it to be harmless, but insisting upon proving the magician to be a fraud, you step into it.

A hot flash of embarassment passes over you as you realize that you are now standing in a cardboard box, in your house, as promised.