Imagine that a spectator freely shuffles a deck of cards, then randomly picks any 4 cards and from them freely decides which one to choose. The assistant delivers into the right hand of the medium, whose back was turned the whole time, the three remaining cards, and she, studying them for a few moments, will be able to guess the chosen card. Not only that but, repeating the experiment with a second spectator, she will guess the chosen card after simply having the three discarded cards announced by her assistant.

This is an original idea, developed by me, to enable the magician's assistant to quickly code any card chosen by a spectator from among four cards a spectator takes at random from within an entire deck of 52 cards, relying solely on the other 3 cards, and thus have the magician correctly identify the card chosen and held by the spectator each time.

Initially, the assistant will simply hand the medium, placed with her back to her, the 3 "discarded" cards in her hand, without uttering a word, and she will be able to divine the chosen card after a few moments (of course, the three cards will be held as usual in the "vertical" direction and all arranged in the same direction).

The experiment will then be repeated, but this time the assistant will merely utter aloud the three discarded cards, without adding the slightest word, and once again the medium, a short while later, will be able to announce the card in the spectator's hand.